cover page of proceedings ENVIROTECH 2008

ENVIROTECH 2008 EMBLEM

Prakasam, V:Decontamination of the environment using biota

Prakasam, V, Decontamination of the environment using biota, (Ed.) S.Jisha, B.Hari & T.K.Remesan, Proc. Nat. Sem. on Env. Biotech. Chall. and Oppor.,  ENVIROTECH-2008, P.G. Dept. of Zoology, S.N.C. Natiika, pp1-6.

(Dept. of Environmental Sciences,  University of Kerala, Thiruvananthapuram-695581, e.mail:prakasamvr@gmail.com)

Abstract

By the activities of man a large number of pollutants are released into the soil and water.  These pollutants include numerous organic and inorganic substances.  They cause water contamination, ecological disturbances and risks to human health.  Therefore steps are on way for clean up of these contaminants.  This paper deals with the use of biota in the removal of such pollutants from the environment, undertaken through a process called remediation.  Remediation includes broadly Phytoremediation, Bioremediation and Zooremediation.

Phytoremediation is the biological treatment process that utilizes plants to enhance degradation and removal of contaminants from soil or ground water.  It includes phytoextraction, rhizofiltration, phytodegradation, phytovolatilization, rhizoremediation and phytostabilization.  By using rhizoremediation technology in constructed wetlands sewage treatment is also carried out.  It is also termed as root-zone technology.  Another important method is called bioremediation.  It is restoration of contaminated environment using microbes.  Based on the location where bioremediation process occurs it can be classified as ex-situ and in- situ bioremediation.  The two major approaches in bioremediation consist of biostimulation and bioaugmentation.  Interestingly GMOS have been recently employed in bioremediation process.  Zooremediation\vermi remediation is another process, though not widely practiced, where the ability of animals in clean up of environmental pollutants is made use of, especially in management of wastes.  All these technologies which are used in treatment water, waste water and soil are detailed in this paper.

Introduction

By man’s developmental activities a large number of pollutants are introduced into the soil, water and air. The pollutants include numerous organic and inorganic substances such as municipal sewage, petroleum products, hazardous wastes from industries, chemicals, agricultural pesticides, fertilizers, heavy metals and radio active materials. Rising environmental contamination day-by-day is causing ecological disturbances and risks to human health. Therefore efforts are on the way for decontamination or clean up of the environment. This paper deals with the use of biota (living organisms) in the removal of pollutants generated from various sources.

Remediation is the transformation of toxic chemicals or substances to less toxic or unharmful substances. Bioremediation is an accepted and important technology for restoration of contaminated environment using microbes. The goal of bioremediation is to stimulate microbes with nutrients and other chemicals that enable them to destroy the contaminants. The approach is to make advantage of the microbial metabolic potential for eliminating environmental pollutants by transformation of organic pollutants through processes such as degradation or mineralization, co metabolism, polymerization or conjugation, accumulation etc. Microbial degradation can also be due to the indirect effect of microbes on chemical or physical environment resulting in a secondary transformation reaction. The efficiency of the microbes in bioremediation depends on different metabolic pathways followed by them to degrade the hydrocarbons. It is also dependent on the genes controlling the enzymes in the degradation process. It leaves less toxic, stable chemical forms of contaminants along with the byproducts like water, CO2 CH4 and H. The process minimizes environmental damage by removing toxic chemicals.  Remediation using plants and animals is respectively phytoremediation and zooremediation.

Phytoremediation: Phytoremediation is a biological treatment process that utilizes natural processes harbored in (or stimulated by) plants to enhance degradation and removal of contaminants from contaminated soil or ground water. It utilizes physical, chemical and biological processes to remove, degrade, transform or stabilize contaminants within soil and ground water.

Phytoextraction: Refers to the extraction and translocation of heavy metals (eg. Cd, Ni, Hg, Se and radionuclides) from shallow contaminated soil to plant tissue. Metal Hyperaccumulators are plants known to extract and selectively absorb large quantities of heavy metals, resulting in their accumulation in plant tissue at greater concentrations than in the contaminated soil. eg.: Sun flower (Helianthus agnus), Indian mustard (Brassica juncea), Crucifers (Thlaspi caerulescens. T. elegans), Violets (Viola calaminaria), Serpentines (Alyssum bertolonii), Corn, nettles and dandelion. Phytoextraction procedure includes (1) Plant selected species in the contaminated area (2) allow the plants to grow, and harvest (3) incinerate the plant tissue and (4) extract heavy metals from the plant ashes for recycling purposes.

Rhizofiltration: This application refers to the use of aquatic plants in wetlands or hydroponic reactors. The submerged roots of such plants act as filters for the absorption of a wide variety of contaminants. When the sorption capacity of the submerged roots is saturated, the plants are removed and replaced.

Phytodegradation: Certain organic pollutants can be removed from soil and ground water through plant uptake. Once the organic xenobiotic enters the plant system, it is partitioned to different plant parts through translocation. Then the plants use detoxification mechanisms that transform parent chemicals to non phytotoxic metabolites. Any number of reactions within the following series may occur.

Phase I             Conversion (includes oxidation, reduction, hydrolysis)

Phase II            Conjugation (chemically link the phase I product to glutathione, sugars or amino acids and thus alters the solubility and toxicity of the contaminant)

Phase III          Compartmentation (Chemicals are conjugated and segregated into vacuoles on bound to the cell wall material- hemi cellulose or lignin)

Some contaminants such as RDX (Hexahydro-1,3,5- trinitro-1,3,5-triazine) may accumulate in leaves. This is of concern, become leaves could fall to the ground potentially reintroducing the contaminant to the environment or to be eaten by animals (potentially impacting food web)

Hydraulic control: Plants are used to prevent off-site migration and /or decrease downward migration of contaminants. Trees and grasses act as solar “pumps”, removing water from soils and aquifers through transpiration. Deep rooted plants are most often used, eg. Poplar (Populus), Willow (Salix). When planted densely (more than 600 acres per acre), poplar and willows usually reach optimum working conditions after 3-4 years during canopy closure when almost all the direct sunlight is intercepted.

Phytovolatalization: In this process the natural ability of a plant to volatize a contaminant that has been taken up through its roots is made use of. It is a potentially viable remediation strategy for many volatile organic compounds such as BTEX (Benzene, Toluene, Ethyl benzene and Xylenes), TCE (Trichloroethylene), Vinyl chloride or Carbon tetrachloride.

Rhizoremediation:This application refers to bioremediation in the root zone. Microbial degradation in the Rhizosphere might be the most significant mechanism for removal of hydrophobic compounds such as PAHS and PCBs. (Polynuclear Aromatic hydro carbon such as Naphthalene, Anthracene etc. Polychlorinated biphenyls which are common dielectric fluids in transformer oil). The strong sorption of such compounds to soil decreases their bioavailabity for plant uptake and phytotransportation but increases their retention in the root zone, which facilities the participation of micro-organisms in the cleanup process. The rhizosphere of most plants promotes a wealth of microorganisms  that can contribute significantly to the degradation of petroleum hydrocarbons during phytoremediation (Deposition of plant- derived carbon sources through root exudation and / or root turn over provides rhizosphere bacteria with numerous organic substrates). Thus the plant can influence the microbial community within its root zone though not directly act on these contaminants.

Phytostabilization: This application aims to prevent the dispersion of the contaminated sediment and soil by using plants (mainly grass) to minimize erosion by wind or rain action.

Root- zone technology: It is a low cost ecotechnology used for treating a variety of municipal, industrial and urban run off waste water. Natural wetlands or constructed wetlands with aquatic plants are made use of in this technology. Three integrated components of the system are the reeds/macrophytes, the gravel bed and the microorganisms.

Reeds (Phragmites karka) absorb oxygen through stomatal openings behind the leaves and transfer it to hollow roots. It then enters the root-zone and promotes the growth of bacteria and fungi. These microorganisms oxidize impurities in the waste water. Macrophytic plants such as water hyacinth and Typha spp. have also shown successful results. Aquatic weeds can be harvested easily. The technology has been applied to different industries like food processing, petroleum refining, chemical industries, breweries and distilleries, plastic, metal, pulp and paper industry.

Vetiveria zizanioides (Ramacham) could be used for Phytoremediation. It is a wonder grass vetiver, globally used for remediation of contaminated land fill sites, stabilization and rehabilitation of eroded mined lands and for waste water treatment. It has been found to withstand extreme temperatures from 10 oC to 48oC and grow in annual rainfall regions from 200-3000mm. It can tolerate very high soil salinity. It can tolerate to very high levels of heavy metals, Al, Mn, As, Cd, Cr, Ni, Cu, Pb, Hg, Se, and Zn. Herbicides and pesticides are very effectively removed by it from the contaminated soil or water (Sinhaet.al., 2005).

Phytoremediation of landfill leachate: Land fills are still the most widely used solid waste disposal method used across the world. Leachate generated from land fill areas exerts environmental risks mostly on surface and ground water, with its high pollutant content, most notably metals, which cause an unbearable lower water quality. During dumping or after the capacity of the landfill has been reached a decontamination and remediation programme should be taken for the area. A recent study (Sogut et.al., (2005) has shown that the perennial plant / Pennisteum clandestinum was quite tolerant to pollution and accumulated heavy metals such as Cr, Ni, Zn and Pb from leachate. This plant was thus found suitable for decontamination and remediation of land fill site.

Phycoremediation: It may be defined in a broad sense as the use of macroalgae and microalgae for the removal or biotransformation of pollutants including nutrients and xenobiotics from waste water and CO2 from waste air. eg: Cyanobacteria used in bioremediation of metals. It is applied to the removal of nutrients, heavy metals and other toxic chemicals from waste and industrial effluents.

Defluoridation: Drinking water from different parts of India is reported to contain excess fluoride. The removal of fluoride from water is called defluoridation. It is possible with indigenous plant materials or aquatic plants. The barks of Moringa indica (drum stick) and Emblica officinalis (Indian gooseberry), the roots of Vetiveria zizanioides(Khuskus) and the leaves of Cynadon dactylon (Bermuda grass) are reported to have appreciable defluoridation capacity (Kartikayan et.al., 2006).   Phytoremediation of Fluoride contaminated ground water using Hydrilla verticellata has also been reported recently (Ambika and Sumalatha, 2005).

Zooremediation: The solid waste from municipal waste (sewage sludge) contains several microbial pathogens such as Salmonella, Shigella and Escherichia. Vermicomposting using the earthworm, Lampito mauritii indicated that these pathogens are removed during this process (Vermiremediation). The midgut analysis also proved the removal of these pathogens by earthworm (Kumar and Sekaran, 2004).   Some animals have the ability to clean up excess nutrients from the waste water. For example, a large scale mussel culture can lead to nutrient decrease in eutrophicated water (Ghosh et.al., 2005).  Marine mussels are also known to concentrate heavy metals in their tissues.

References

Mc. Cutcheon., J and L, Schnoor (2003).  Phytoremediation-transportation and control of contaminants, John Wiley & Sons. Inc., New Jersey.

Agarwal, S. K (2005). Wealth and waste, APH publishing corporation, New Delhi.

Ghosh, T. K (2005). Biotechnology in environmental Management Vol. I & II. APH publishing corporation, New Delhi.

Alvarez, P. J. J and W. A, Illman (2006). Bioremediation and Natural Attenuation, Wiley Interscience A. John Wiley & Sons. Inc. New Jersey.

Agitha, T.G – BIOTECHNOLOGY AND IPR

Agitha, T.G, Biotechnology and IPR, (Ed.) S.Jisha, B.Hari & T.K.Remesan, Proc. Nat. Sem. on Env. Biotech. Chall. and Oppor.,  Envirotech-2008, P.G. Dept. of Zoology, S.N.C. Natiika, pp57-62

(IPR Chair, School of Legal Studies, CUSAT, Cochin, agitha1@rediffmail.com)

Abstract

The recent advancements in the research and inventions in the field of biotechnology paved way for the demand for strengthening IPR protection, especially patent protection, in that area of research. As far as India was concerned, prior to signing the Final Agreement on GATT and thereby submitting itself to the obligations under the TRIPS Agreement, India was not extending patent protection for products or processes of biotechnological inventions. However, signing of the TRIPS agreement changed the entire scenario and India changed its Patents Act so as to extend its protection to the field of biotechnological research. It also enacted the Protection of Plant Varieties and Farmers’ Rights Act, 2001 (PVFRA) to protect the Plant Breeders’ Rights so as to meet the TRIPS obligation.

The problems created by IPR protection of biotech-based inventions are increasing rate of bio-piracy, depletion of indigenous genetic resources, blocking of further research etc. As India is a signatory to the GATT Agreement, what we can now do solve theses problems is to make our laws more congenial to Indian environment within the available limits of TRIPS, making use of the flexibilities therein and also by interpreting the law to suit this objective. One mode of achieving this objective is to strictly interpret the patentability requirements such as novelty, inventive-step and industrial application. This ensures that knowledge already in the public domain is not allowed to be privatized and it could, to a large extent, remove the blocking on further research. Attempts could also be made to enforce the obligation under Convention on Biological Diversity (CBD) to allow access to genetic resources only after getting prior informed consent from the owners of genetic resources and associated traditional knowledge and disclosing the source and origin of the genetic resource and traditional knowledge and after agreeing to share the benefits arising out of the commercial exploitation of such genetic resources. Admitting that intellectual property protection may act as incentive to further research and invention, one should not forget about the ultimate goal of Intellectual property protection, namely, public access to the subject matter of protection at an affordable price. Simultaneously access to genetic resources and associated traditional knowledge also is attempted to be controlled by the Biological Diversity Act, 2002 enacted for implementing the objectives of the CBD.

Introduction

Though biotechnology and research could be dated back to centuries, its relevance in industry and commerce is of very recent origin.  This relevance is due to the modern developments in biotechnology like molecular biotechnology, especially, recombined DNA Technology. Commercial success of biotechnology and increasing private investment in the biotechnological research necessitated IP protection for the successful exploitation of biotechnological research by the industry.  This demand resulted in the inclusion of the TRIPS Agreement in the GATT final text with demands like patent protection for biotechnological inventions, protection of new plant varieties either by patent or by other effective sui generis system etc.

Before the TRIPS Agreement many countries excluded biotechnological inventions from the purview of patentable inventions as such inventions were considered naturally occurring and it was thought unethical to allow monopoly over such products.  However, under the TRIPS it is now mandatory for the member countries to extent patent protection to all fields of technology including biotechnology provided such inventions are new, involving  inventive step  and capable of industrial application. Thus now though plants, animals, essentially biological processes for the production of plants and animals are not patentable, micro-organisms and non-biotechnological and micro-biotechnological processes for the production of plants and animals are patentable.

The major problems with the extensive protection of biotechnological inventions are 1) Blocking of further research by diluting the patentability standards like novelty, inventive step and industrial application, 2) increasing cost of product of  biotechnological research making them unaffordable to the common man; (3) increasing tendency to indulge in bio-piracy i.e., plundering of genetic resources and associated traditional knowledge without consent and without  remunerating  its holders/owners (4) depletion of indigenous genetic resources etc.

These problems, however, could be solved to some extent by making full use of the flexibilities available in the TRIPS agreement in national IP laws.  Though the TRIPS agreements has stated that biotechnological inventions are to be given patent protection, it does not lay down the standard of novelty, inventive step and industrial application.  If the standards of novelty and inventive step in the national patent law is made stricter, minor modifications or minor innovations will be excluded from patent protection and thus it reduces the blocking Effect of Patent Protection

The novelty requirement under the patent Act excludes inventions which is published or used prior to the filing of patents.  The inventive step requirement demands that inventions, to be patented, should not be obvious to a “person skilled in the art” in the light of prior knowledge or information.  An invention could be considered as obvious to a person skilled in the art if it is an expected result of the research.  The main problem with biotechnological research is that mostly the results of such researches are expected and the researcher’s skill lies in successfully accomplishing the result which is the real tough job in the biotechnological researches.  However, a strict definition of patentability standards avoid monopolization of knowledge in the public domain under the guise of minor modifications.

India tries to accomplish this result by rendering the novelty & inventive step standards comparably strict.  In order to satisfy the inventive step standard, under Indian law, the invention should have technical advancement as compared to existing knowledge or economic significance on both.  Similarly mere discovery of a new form of a known substance or any new property or new use for a known substance etc are considered as non-patentable.  It also excludes methods of agriculture or horticulture, from patentable inventions.  Any process for the medicinal, surgical, curative or diagnostic techniques for the treatment of animals and human beings one also not patentable.  Similarly, plants, animals, seeds etc are not patentable.

In order to curtail the other risks associated with IP protection of biotechnological inventions the most effective method is to ensure the requirements under the Convention on Biological Diversity (CBD) are effectively complied with.  The CBD, inter alia, insists that the IP protection of inventions based on biological resources are to be in tune with the requirements in the CBD in this respect.  The CBD recognizes national sovereignty of over biological resources. Therefore it stipulates that access to genetic resources and traditional knowledge (T.K) associated with such resources are to be strictly controlled/regulated.  The CBD mandates that such access has to be made only after getting the ‘prior informed consent’ of the Genetic resources and TK.  In order to ensure this, the source and geographical origin of the Genetic Resources (CGRS) and TK has to be disclosed in the patent application.

The CBD also necessitates benefit shaping if the Genetic Resources & TK is commercially exploited or used in producing any form of IP.  Measures to ensure compliance with the CBD requirements are introduced in the patents Act, protection of plant varieties and Farmers’ Right Act, and the biological diversity Act in India.

The Patents Act: The patents Act excludes an invention which is in effect traditional knowledge or which is an aggregation or duplication of known properties of traditionally known components from patent protection.  The Indian patents Act also requires disclosure of source and geographical origin of biological materials in the patent application.  But the Act does not require any such disclosure with respect to any traditional knowledge associated with such genetic resources.  Neither does it require PIC it also does not envisage benefit sharing.  However, in order to ensure compliance with the disclosure requirement the Act has included provisions for opposition to grant of patent if there is no such disclosure.  The Act also provides for revocation of patent if the patent holder fails to disclose or wrongly discloses the source and origin of the biological material.  There is also provision for revoking the patent if the invention is anticipated due to knowledge within my local or indigenous communities in India or elsewhere.

The Biological Diversity Act (BDA): The Biological Diversity Act attempts to regulate access to genetic resources and associated TK and ensures benefit sharing as envisaged by the CBD.  The national Biodiversity Authority (NBA) is entrusted with the duty to grant approval for accessing biological resources by non-citizens or NRIs and for transferring the result of research relating to Biological materials from India for monetary consideration to non-Indians or NRIs.  The power to grant approval to any person for applying for Intellectual Property Rights is also entrusted to the NBA.  NBA has also the duty to ensure that Benefit sharing is agreed upon while accessing biological resources.  And the amount collected by way of benefit sharing has to be deposited in the National Biodiversity Fund if the owners of the biological materials and TK are not identifiable.  If they are identifiable the amount can go directly to them.  However, such a system envisaged under the Biological Diversity Act often proves to be faulty.

Since the mechanism to control access and ensure benefit sharing is highly centralized, more often, there is no effective supervision over these matters.  The State Biodiversity Boards and the Biodiversity Management Committees constituted in the local level are absolutely powerless.  An effective implementation of the provisions in the Act necessitates absolute decentralization.  Only the local level bodies are capable of identifying and controlling bio-piracy.  And the participation of interested persons could ensure the effective working of the system.  The Fund, which is also now centralized, needs to be decentralized.

Protection of Plant Varieties and Farmers Rights Act (PVFRA): For ensuring disclosure requirement, the Act provides that the application for registration should contain 1) Complete passport data of the parental line from which the variety has been derived; 2) Geographical location in India from where the genetic material has been taken; 3) All information relating to contribution of any farmer, village community etc. in developing the variety; 4) Information regarding the use of genetic material conserved by any tribal or rural families. For ensuring benefit sharing it necessitates that 1) after issuing the certificate of registration the Authority invites claims of benefit sharing from any person, group, or govtal or non-govtal organization 2) any person, group, or governmental or non-governmental organization may also file, with the prior permission of the Central Govt., any claim attributable to the contribution of the people of that village or local community 3) The amount in both the cases is recoverable as arrears of land revenue, and shall be deposited by the breeder in the Gene Fund. In order to ensure prior informed consent the Act requires that 1) the application should contain a declaration that the genetic material acquired for breeding has been lawfully acquired and if the information required for registration is not given or if wrong information is given the right granted under the Act can be revoked.

There is also provision in the Act to control terminator technology. For example, every application for registration of new varieties has to be accompanied by an affidavit stating that the variety does not contain any gene or gene sequence involving terminator technology. The Act also excludes varieties which involve any technology which is injurious to life or health of human beings animals or plants, including terminator technology from registrability. There is also provision in the PVFRA to exclude from registration a variety if the commercial exploitation of it is injurious to animal or plant health or environment. The Act enables any person to oppose registration of new varieties on the grounds of public interest and adverse effect on environment.

Sarita et al.,Effect of lactic acid…

JAYASREE ET AL., DEVELOPMENT OF A WINDROW…

Jayasree, S*., Saritha Ravindran**, Saritha.K.P** and Renjini Balan**, Decontamination of the environment using biota, (Ed.) S.Jisha, B.Hari & T.K.Remesan, Proc. Nat. Sem. on Env. Biotech. Chall. and Oppor.,  Envirotech -2008, P.G. Dept. of Zoology, S.N.C. Natiika, pp1-64-70.

(*Department of Zoology, **Department of Biotechnology, Mercy college, Palakkad)

Abstract

Waste has become an index of growth. Utilization of waste materials for productivity purposes is important for both economic and environmental reasons. Composting can be economically viable for managing manure. Windrow composting is an important aspect as it converts waste to wealth. Composting is a controlled self-heating, aerobic solid phase biodegradation process of organic materials. In this context, a modified windrow composting technique amended with farmyard manure was developed for the efficient utilization of solid waste produced at Mercy college campus which comes around 18 acres of land. Under optimal conditions the composting process can be divided into four phases (1) an initial mesophilic phase (10-420C), which may last for only a few hours or a couple of days, (2) a thermophilic phase (40-700C) lasting a few days or weeks (3) Second mesophilic phase during which mesophilic organisms, often dissimilar to those of the first mesophilic phase, recolonize the substrates and (4) the maturation or curing and stabilization phase which can last for several weeks to months. Half ton capacity plant which have developed at Mercy College campus have a turnover potential to produce 150 Kg compost every 60 days basis, which brings revenue to the college, makes the campus clean and also provide employment opportunity.

Introduction

Composting is the controlled decay of organic matter in a warm moist environment by the action of bacteria, fungi and other organisms (Salvator and Sabee, 1995). Windrow composting is a process for biodegrading organic material aerobically. The process produces heat that destroys pathogens and produces a stabilized compost product for use as mulch, soil conditioner, and topsoil additive. The organic material is left to decompose outdoors, aided only by watering and mechanical turning for aeration. This method is simple, non-intensive, has a very low capital cost, and is commonly used by farmers, municipalities, and waste processing corporations. It is the slowest large-scale method used to produce compost. Windrow composting can be used to process yard waste, food, paper, and sewage sludge.

The process of composting begins with collecting, receiving, processing and storing feed stock materials. These steps are then followed by mixing and pile construction. The compo-stable materials must be screened or hand picked for non-biodegradable materials, and then chipped, ground, or shredded into uniform particles that will decompose quickly. The high-carbon, dry wood and paper waste should be mixed in equal proportion with high-nitrogen, high moisture grass clippings and food waste to provide balanced nutrition for the organisms of decomposition. The material is then formed into piles to decompose.

Under optimal conditions the composting process can be divided into four phases (1) an initial mesophilic phase (10-420C), which may last for only a few hours or a couple of days (2) a thermophilic phase (40-700C) lasting a few days or weeks (3) Second mesophilic phase during which mesophilic organisms, often dissimilar to those of the first mesophilic phase, recolonize the substrates and (4) the maturation or curing and stabilization phase which can last for several weeks to months (Hoitink and Boehm,1999; Insam and de Bertoldi, 2003).

In this work a novel solid waste management practice was introduced. Windrow composting for 18 acres of Mercy college campus whose waste generation resembles a typical urban community, equivalent to a ward under City Corporation’s jurisdiction.

Materials and methods

Site Selection and construction of windrow compost yard: Composting is a viable way to turn potentially damaging organic byproducts into productive resources. The college spread over 18 acres includes the main block comprising the various departments with Laboratories. It has a Library, Auditorium, Hostel, Mess, Canteen, Convent, Family& Student Counseling Centre, a Mercy Home, an animal house, a cattle and pig farm. The waste generated from Mercy College and facilities daily can be utilized for the Windrow composting programme. Plot in front of the auditorium near the waste dumping site was selected for the construction of windrow compost yard.

Steps Involved in Windrow Composting Technique
Segregation and Storage: Two large bins (green and white) were placed at appropriate locations at the college campus for storing waste. Segregation of the College campus solid wastes into the groups of organic, inorganic, recyclables and hazardous wastes were easily done by the students. The segregated waste is temporarily stored in the storage area of the compost yard so as to prevent littering.

Processing procedure: The large pieces of solid waste were ground into small pieces and dumped in long rows, called windrows. Waste and cow-dung inoculum in the ratio 10:1 is spread in alternate layers, forming a windrow. The height of the heap is kept up to 1.5m and the moisture content is maintained at 50-60% during the composting. Excess moisture will result in anaerobic conditions and create odour problems. The windrow is covered with High Density Poly Ethylene sheet Silpaulin 150 gsm to avoid scavenging by birds, dogs etc, maintain required temperature by avoiding heat dissipation, destroy pathogens by providing temperature in the range of 60-700C and destroy the weed seeds.

Composting: After a windrow is laid in place, the material is dampened by spraying water. The water aids in the composting process and helps minimize wind-blown dust. Every 10th day, each windrow pile was turned manually using iron rod and helps to agitate the material. This breaks down the material into even smaller pieces and exposes it to oxygen, which aids in the decomposition process. After the windrow is turned, it is sprayed with water again. This process continues for two or three months. In hot, dry weather, the windrows may have to be watered more often. During decomposition, the internal temperature of the pile may reach 130°F (54°C), which helps kill many of the weed seeds that might be present.

Curing: The raw compost is scooped up with a front loader and moved to a large conical pile where it is allowed to finish the decomposition process over a period of several weeks. This process is called curing and it allows the carbon and nitrogen in the compost to adjust to their final levels.

Screening: After the compost has cured, it is scooped up with a front loader and dumped into the hopper of a rotary sieve. This device consists of a large cylindrical sieve rotating on an axis that is slightly inclined above the horizontal. The openings in the sieve are about 0.5 in (1 cm) in diameter. The compost is fed into the raised end of the rotating sieve. As the compost tumbles its way down the length of the rotating sieve, the smaller material falls through the sieve and is moved to a storage pile and larger material that cannot pass through the sieve falls out the lower end of the cylinder and is either returned to the compost piles for further decomposition or is transferred to vermi compost unit.

Quality control: Composting companies regularly have their finished compost tested to ensure it is free of harmful materials and contains the proper amounts of plant nutrients. The tests measure the size of the particles, moisture level, mineral content, carbon-to-nitrogen ratio, acidity, nutrient content, weed seed germination rate, and many other factors. For example, waste particles should be between 0.5-2 in (1.2-5 cm) in diameter in order to encourage the flow of oxygen within the compost. Likewise, the level of moisture should be above 40% to facilitate the compost process. Moisture levels that dip below 40% slow the process and present the risk of spontaneous combustion. Also, the ideal ratio of carbon to nitrogen is 30:1. The ideal balance maintains a healthy microbial population that speeds decomposition and minimizes odor.

Packing and Distribution: Much of the finished compost is loaded into large and sold in bulk to nurseries, and other commercial customers. Some of it is sealed in 1 kg plastic bags for retail sale to college garden.

Composting process

Result

Half tone capacity Windrow Composting yard was constructed. This compost yard can process 0.5 tone solid waste /week. Processing time required is two months.
Income to College (From one tone of waste treated 300 Kg compost is produced), Windrow compost 3 tone @ Rs.5/kg 15,000.
Clean campus
Garden manure is free of cost.
Students and self help group people are trained can promote employment opportunity.

The composting is the resultant of the microbial action taking place inside the windrow. In the first few days the mesophilic organisms act and there after the thermophilic organisms take over the decomposition process. The aerobic process facilitates exothermic reaction, generate temperature up to 800C and kill pathogens and weed seeds in that process. Temperature increase beyond 700C will inhibit further microbial activity. Hence temperature in the heap should be maintained at 50-600 C, which is observed to be optimum for the degradation of wastes.

Discussion

Making and using compost as a soil amendment has many potential benefits for agriculture and the rest of society (Ryckeboer, et.al., 2003). Composting adds value to crop residues, manures, and other organic wastes by biologically transforming them into a valuable resource that can enhance soil fertility by improving the biological, physical, and chemical properties of the soil. Composting is a viable way to turn potentially damaging organic byproducts into productive resources. Organic wastes can be expensive to manage and cause potential health and environmental problems. If not managed properly, unutilized agricultural materials can produce pollutants such as nitrates that end up in drinking water or methane and other gases that end up in the atmosphere. When used properly, compost enhances plant health and productivity, partly because compost contains essential plant nutrients and partly because compost increases the soil’s ability to retain and store nutrients. The goal of this activity is to introduce students to the idea of biological decomposition and engage students in the process of managing organic wastes through composting. Four ‘R’s (Refuse, Reuse, Recycle, Reduce) to be followed for waste management.

1. Refuse: Instead of buying new containers from the market, use the ones that are in the house. Refuse to buy new items though you may think they are prettier than the ones you already have.
2. Reuse: Do not throw away the soft drink cans or the bottles; cover them with homemade paper or paint on them and use them as pencil stands or small vases.
3. Recycle: Use shopping bags made of cloth or jute, which can be used over and over again [will this come under recycle or reduce?].Segregate your waste to make sure that it is collected and taken for recycling.
4. Reduce: Reduce the generation of unnecessary waste, e.g. carry your own shopping bag when you go to the market and put all your purchases directly into it.

References

Salvator, K and W.E, Sabee (1995). Evaluation of fertilizer value and nutrient release from corn and soybean residues under laboratory and greenhouse conditions. Commu. Soil/Svi., Plant Anal., 26: pp469-484.

Insam and M, deBertoldi (2003). Microbiology of the composting process, In: Golueke C., Bidingmair W.,de Bertoldi M., Diaz l.,eds, Compost Science and Technology, Elsievier Science.

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Neelakandan, C.R:ETHICAL AND MORAL ISSUES …..

Neelakandan, C.R, Ethical and Moral Issues in Environmental Biotechnology, (Ed.) S.Jisha, B.Hari & T.K.Remesan, Proc. Nat. Sem. on Env. Biotech. Chall. and Oppor.,  Envirotech-2008, P.G. Dept. of Zoology, S.N.C. Natiika, pp 9-26

‘Thanal’, Kizhakkekkara Road, Thrikkakkara P.O, Cochin 21.

Abstract

The recent advancements in the research and inventions in the field of biotechnology paved way for the demand for strengthening IPR protection, especially patent protection, in that area of research. As far as India was concerned, prior to signing the Final Agreement on GATT and thereby submitting itself to the obligations under the TRIPS Agreement, India was not extending patent protection for products or processes of biotechnological inventions. However, signing of the TRIPS agreement changed the entire scenario and India changed its Patents Act so as to extend its protection to the field of biotechnological research. It also enacted the Protection of Plant Varieties and Farmers’ Rights Act, 2001 (PVFRA) to protect the Plant Breeders’ Rights so as to meet the TRIPS obligation.

The problems created by IPR protection of biotech-based inventions are increasing rate of bio-piracy, depletion of indigenous genetic resources, blocking of further research etc. As India is a signatory to the GATT Agreement, what we can now do solve theses problems is to make our laws more congenial to Indian environment within the available limits of TRIPS, making use of the flexibilities therein and also by interpreting the law to suit this objective. One mode of achieving this objective is to strictly interpret the patentability requirements such as novelty, inventive-step and industrial application. This ensures that knowledge already in the public domain is not allowed to be privatized and it could, to a large extent, remove the blocking on further research. Attempts could also be made to enforce the obligation under Convention on Biological Diversity (CBD) to allow access to genetic resources only after getting prior informed consent from the owners of genetic resources and associated traditional knowledge and disclosing the source and origin of the genetic resource and traditional knowledge and after agreeing to share the benefits arising out of the commercial exploitation of such genetic resources. Admitting that intellectual property protection may act as incentive to further research and invention, one should not forget about the ultimate goal of Intellectual property protection, namely, public access to the subject matter of protection at an affordable price. Simultaneously access to genetic resources and associated traditional knowledge also is attempted to be controlled by the Biological Diversity Act, 2002 enacted for implementing the objectives of the CBD.

Introduction

First of all we cannot differentiate between various branches or applications of Biotechnologies because the environmental, health and other social, moral and ethical impacts risks or dangers are the same irrespective of their application.

Biotechnology, or the genetic modification of living materials, has ignited heated debates over trade policy. Innovations in the manipulation of microbes, plants, and animals raises serious ethical questions related to the commoditization and exchange of living organisms. In the arena of trade policy, these ethical questions pose a unique economic dilemma: to what extent should trade policy reflect moral and ethical judgments about the fruits of biotechnology?.

Agriculture is the big winner as modern biotechnology progresses. Past attempts for the long term control of nematode and Phylloxera in vineyards with strong chemicals have had limited success.  However, safe methods, using biotechnology, can supply special nutrients for the beneficial microbes in the soil.  Several microbial strains, including Actinomycetes, which are typically native in the soil, produce enzymes that open the skin of the damaging Nematode or Ahylloxera, diminishing their population.  The soil comes alive with beneficial creatures that can naturally control pest and disease problems.  In addition, the trillions of beneficial microbes work to adjust pH, make nutrients more available, improve plant health and increase crop quality and yields.

Debate on Genetically Modified Foods: The principal cause of the debate surrounding products of biotechnology is the uncertainty of the long-term health and environmental effects of genetically modified living materials. Though many scientists believe GM foods to be safe, a small but influential group of researchers maintain that uncertainty about their effects on human health justifies extreme precaution, including the possible use of trade restrictions. Some supporters of GM foods agree that rigorous testing and research should continue but that in the meantime the benefits of heartier or enriched crops are too great to ignore and are essential in eliminating world hunger and malnutrition. Advocates of sustainable development are also wary of the long-term effects that GM crops could exert on the environment.

Agricultural concerns center on issues of ‘genetic pollution’ or the genetic flow from GM crops to unmodified plants in the wild. Transfer of genes from GM to wild plants could create health problems in humans, anti-biotic resistance in plants and associated insects, long-term damage to ecosystems, loss of biodiversity, and lack of consumer choice.

Defenders of biotechnology often argue that genetic manipulation holds the key to eliminating hunger and suffering across the world. One commonly cited example is ‘Golden rice’ which scientists have engineered to produce extra Vitamin A. The rice has been hailed as a godsend for malnourished people in the developing world because Vitamin A helps prevent blindness. Critics take two different stances on these wonder-foods. Some refer to recent studies and statements by doctors that Golden rice is not a sufficient source of vitamin A. Specifically, people with diarrheal diseases are incapable of absorbing vitamin A from the rice, thus people in developing countries who commonly suffer from diarrheal disease and vitamin A deficiency remain afflicted by both. Other critics reply that ‘Franken foods’ are the wrong answer to the problems of hunger and malnutrition, which they claim are the outcomes of distributional problems. Instead of posing a viable long-term solution, GM foods distract from and exacerbate the real issues involved.  Moreover food is not just something to sustain life or just the nutrition. But it has social, cultural, economic, geographical and many more contexts.

Producers of GM crops argue that biotechnology could be the world’s cure for hunger. They cite the technology’s ability to produce high yields, resist natural disasters such as drought and certain viruses, and be enriched with vital nutrients that starving people are likely to lack.

However, aid agencies and anti-GM countries argue that in regards to eliminating world hunger, alternatives to GM crop production have not been sufficiently researched. In fact, they note that many countries where hunger is a major problem do produce adequate amounts of food to feed their population. Hunger, they argue, is not only a function of agricultural yield; it is also a function of mismanaged government and a series of other factors, which technology cannot resolve.

At present there is no international law dealing with aid shipments of GM crops to needy countries. However, debates over a country’s right to refuse GM food aid during a famine are bringing this issue to the forefront of biotechnology concerns. Production may be carried out by using intact organisms of bacteria, fungi and other microbes, or by using natural substances created by the organisms, such as enzymes.  The United States, and specifically California, is a world leader in the area of new biotechnology, a multi billion dollar industry.

The use of new biotechnology for cleaning up major environmental concerns may be in its infancy, but practical applications are underway.  Many problems associated with water, air, and soil contaminants can be fixed with new biotechnology.  Modern biotechnology is currently being used in soils for growing better crops, in wastewater for eliminating odors and meeting regulatory requirements, in toxic waste clean-up and many other areas.

There is a dilemma with biotechnology concerning on-going research.  What takes place on a small scale under controlled laboratory conditions is completely different than what occurs in a large scale “real world” situation.  An example is in cheese manufacturing where thousands of pounds are made at one time with microbes added prior to aging.  It would be very difficult to make a one pound batch with the same characteristics as a large batch because of the transformations caused by the microbes and enzymes.

Environmental BT: Historically, industry has had difficulty dealing with wastewater problems.  Sewage treatment plants around the world have included the use of native microbes that exist in their conventional treatment systems.  By using biotechnology, the treatment process can be optimized with the proper strains of selected microbes.  These microbes are more efficient at eating the waste, which causes high Biochemical Oxygen Demand (BOD) in the water.  Special nutrients enable the microbes to reproduce and thrive in the system.  The treatment plant becomes more efficient without incurring the major expense of building larger facilities.  The waste is more completely broken down for safer discharge, the BOD is decreased, and the corresponding odors are significantly reduced or eliminated.

Dairy and hog operations that discharge wastewater into ponds or fields are also able to benefit from new biotechnology by lowering the nitrate concentration of their waste stream as well as eliminating odors associated with the waste.  For instance, dairy wastewater is loaded with sanitizers and disinfectants that keep our milk supply safe for drinking.  While these products help ensure the safety of our milk, they cause problems for the useful microbes in the wastewater.  By treating the wastewater with the proper strains of microbes and nutrients, the sanitizers, disinfectants, and manure are broken down prior to field application.  As a result, the crops benefit from a more productive soil.  Food processing companies can also handle many of their environmental waste problems by using modern biotechnology.

Fundamental Weaknesses of the Concept of BT

Imprecise Technology: A genetic engineer moves genes from one organism to another. A gene can be cut precisely from the DNA of an organism, but the insertion into the DNA of the target organism is basically random. As a consequence, there is a risk that it may disrupt the functioning of other genes essential to the life of that organism (Bergelson, 1998).

Side Effects: Genetic engineering is like performing heart surgery with a shovel. Scientists do not yet understand living systems completely enough to perform DNA surgery without creating mutations which could be harmful to the environment and our health. They are experimenting with very delicate, yet powerful forces of nature, without full knowledge of the repercussions (Washington Times, 1997; The Village Voice 1998).

Widespread Crop Failure: Genetic engineers intend to profit by patenting genetically engineered seeds. This means that, when a farmer plants genetically engineered seeds, all the seeds have identical genetic structure. As a result, if a fungus, a virus, or a pest develops which can attack this particular crop, there could be widespread crop failure (Robinson, 1996).

Threatens Our Entire Food Supply: Insects, birds, and wind can carry genetically altered seeds into neighboring fields and beyond. Pollen from transgenic plants can cross-pollinate with genetically natural crops and wild relatives. All crops, organic and non-organic, are vulnerable to contamination from cross-pollinattion (Emberlin et. al., 1999).

Health Hazards

No Long-Term Safety Testing: Genetic engineering uses material from organisms that have never been part of the human food supply to change the fundamental nature of the food we eat. Without long-term testing no one knows if these foods are safe.

Toxins: Genetic engineering can cause unexpected mutations in an organism, which can create new and higher levels of toxins in foods (Inose, 1995 and Mayeno, 1994).

Allergic Reactions: Genetic engineering can also produce unforeseen and unknown allergens in foods (Nordlee, 1996).

Decreased Nutritional Value: Transgenic foods may mislead consumers with counterfeit freshness. A luscious-looking, bright red genetically engineered tomato could be several weeks old and of little nutritional worth.

Antibiotic resistant bacteria: genetic engineers use antibiotic-resistance genes to mark genetically engineered cells. This means that genetically engineered crops contain genes which confer resistance to antibiotics. These genes may be picked up by bacteria which may infect us (New Scientist, 1999). Problems cannot be traced—without labels, our public health agencies are powerless to trace problems of any kind back to their source. The potential for tragedy is staggering.

Side effects can kill: 37 people died, 1500 were partially paralyzed, and 5000 more were temporarily disabled by a syndrome that was finally linked to tryptophan made by genetically-engineered bacteria (Mayeno, 1994).

Environmental Hazards: Increased use of herbicides—scientists estimate that plants genetically engineered to be herbicide-resistant will greatly increase the amount of herbicide use (Benbrook, 1999).  Farmers, knowing that their crops can tolerate the herbicides, will use them more liberally.

More pesticides: GE crops often manufacture their own pesticides and may be classified as pesticides by the EPA. This strategy will put more pesticides into our food and fields than ever before.

Ecology may be damaged: The influence of a genetically engineered organism on the food chain may damage the local ecology. The new organism may compete successfully with wild relatives, causing unforeseen changes in the environment (Metz, 1997). Gene Pollution cannot be cleaned up once genetically engineered organisms, bacteria and viruses are released into the environment it is impossible to contain or recall them. Unlike chemical or nuclear contamination, negative effects are irreversible.

DNA is actually not well understood. 97% of human DNA is called junk because scientists do not know its function. The workings of a single cell are so complex; no one knows the whole of it (San Diego Union-Tribune, 2000).  Yet the biotech companies have already planted millions of acres with genetically engineered crops, and they intend to engineer every crop in the world. The concerns above arise from an appreciation of the fundamental role DNA plays in life, the gaps in our understanding of it, and the vast scale of application of the little we do know. Even the scientists in the Food and Drug administration have expressed concerns.

Some basic issues

Life web on the earth is so complex: Any impact on one end may (will) affect the whole web in a manner which may not be predictable. Inter disciplinary approach is a must. Also a holistic approach considering the scientific truth that whole system is interdependent. Most of the other biosystems are not dependant on man for their survival but the reverse is not like that. Humankind is fully dependant on the bio systems.  Our concerns shall not be limited to the short scale in space and time.

Technology is not value neutral: The use- abuse model is not directly applicable to any of the modern technologies.  These technologies by itself is destructive even if we find some short term benefits. Good examples are Nuclear and green revolution.  When we consider the long term impacts of these technologies the destruction caused by them are not very much reversible.

Ethics and Morality varies from time to time and from societies to societies. The value systems vary among different categories of people. They are interrelated with culture, economy, politics etc.

Risk- Benefit Analysis: This is not just mathematical function like 1+1 etc.  Eg. Some systems may have 100 benefits to list and just two risks. But one risk is that it may create a virus which can destroy human bodies in minutes. This effect may be visible after 10 years. Can we accept this? Otherwise if it affects certain species in one year time and later we find that destruction of these species may lead to a catastrophy for humanity.  Can we accept this?.

Perspective of benefit may vary from group to group also Eg. GDP growth or Per Capita income etc may be an important indicator of the progress of a society.  But that may not be a positive sign for many.  This depends on the social structure.  How we select between crop and Herbs? For Mother Nature there is no such classification. What is our moral authority to destroy a life form?. The ethics is only that of business.

Necessity of the Technology: How can we evaluate a technology? Can we confirm that the latest or fastest or cheapest is the best? Is it a universally acceptable principle? If not what shall be the criterion? (E.g. of Ford car in Wardha Asram).

People’s acceptability: Can we consider this as a measure especially in a democratic system? Vested interests can create the necessity and acceptability. We consider it as our freedom. But the reality is that it is slavery. People’s perceptions change very fast E.g. up to 1996, GM food was acceptable to EU countries. But suddenly it changed especially against GM food and Cloning.

Belief in the systems: We can argue that we have control and supervisory mechanism to protect us. But how much dependable are these systems? We have many experiences of Regulatory bodies like GEAC in the cases of BT. Cotton or Brinjal. Especially in the era of imperialistic globalization all state apparatuses from legislature to Judiciary are not reliable. Anything can be bought. In this context it may be advisable to avoid a risky choice.

Patenting Life: Biotechnology issues related to intellectual property rights are concerned with the moral and ethical implication of patenting living organisms. These concerns are linked to fears that biotechnology will transfer resources from the public sphere to private ownership via the enforcement of intellectual property rights. Firms that have invested in the development of genetically modified varieties want to protect their proprietary knowledge, but many farmer groups have protested that enforcing intellectual property rights will disrupt their access to seed. Farmers accustomed to harvesting and replanting their seeds are not willing to pay for GM seeds year after year. These debates draw attention to the controversial TRIPs Article 27.3(b), which exempts certain life forms from patentability but requires countries to establish some form of protection for plant varieties.

Multiple Forums for Debate: There are a number of forums attempting to guide the international debate on biodiversity. At the WTO level, the March 8, 2004 TRIPS Council meeting saw the nations of Brazil, Bolivia, Cuba, Ecuador, India, Pakistan, Peru, Thailand and Venezuela called for greater urgency in resolving possible conflicts between the TRIPS agreement and the Convention on Biological Diversity (CBD). The Convention was established with the three main goals of conservation of biological diversity, sustainable use of its components and the fair and equitable sharing of the benefits from the use of genetic resources. The CBD is concerned with preservation while the TRIPS agreement examines the intersection of business and biodiversity and so there would naturally be conflicts between the different missions of the two arenas. The U.S. and Japan have called for discussions to take place in the World Intellectual Property Organization (WIPO) forum instead which is mandated to increase intellectual property protection. Meanwhile, free trade agreements continue to change the intersection of trade law and biotechnology. For instance the U.S.- Central American Free Trade Agreement encourages plant patentability, a step beyond that of the TRIPS agreement, reflecting the U.S. desire for intellectual property protection to encourage innovation.  It also and forbids reversion to weaker patent laws once stronger laws have been enacted.

Current Events: Since 1998, the EU has placed a moratorium on the import of genetically modified living materials, citing insufficient proof that these organisms do not cause long-term negative effects to public health.  The ban has frustrated the US, the largest producer of genetically modified crops, and it has long been threatening to file a formal complaint with the WTO over the EU ban, citing the ban as unjustified and discriminatory.  In July 2003, however, the EU lifted the five-year ban on the condition that all products containing at least 0.9% genetically altered ingredients are explicitly labeled as such.  Despite this move, which would finally allow US farmers of genetically altered crops access to European markets, the US, Canada, Argentina, Brazil and numerous other countries filed a formal complaint with the WTO in May 2003. They argued that the EU’s moratorium on the approval of new GM foods violated WTO rules, and cost their farmers hundreds of millions of dollars in lost revenues each year.  These countries have also expressed dissatisfaction with the EU’s new stipulation that all GM foods be labeled, but the EU has called the complaint unnecessary in light of their new policy toward GM foods.  In March 2004 a WTO panel was appointed to rule on the US-Argentina-Canada complaint against the EU de facto moratorium on the approval of new GMOs.

The issue of biotechnology’s ability to battle hunger has also manifested itself in the complicated cases of 6 African nations, who have banned GMO food aid.   Zambia rejected GM food aid while it was hard hit by a famine in 2003 for health and environmental reasons.  Zambia voiced concern that GM seed might contaminate their local crop, thus jeopardizing their ability to continue shipping organically grown crops to the EU. The fear that millions in Zambia might starve proved false and the nation ended up producing a 120,000 ton surplus.  US food aids which most likely contain GM crops had to be rerouted by the UN World Food Program which distributes the aid.  The US has said that it is impossible in practice to keep separate GM foods from non-GM foods.   It is not just for or against argument.  Because by the time we argue the actions might have taken place which we are not able to correct.

What do Scientists Say about the Dangers of Genetic Engineering?

“By taking a stand against genetically engineered foods, Mothers for Natural Law has come out as protectors of values that cannot be denied without placing all of humanity in jeopardy.  These include the health and safety of our children and all generations to come; the welfare of the environment; and our fundamental human rights.”- from Genetically Engineered Foods—Good for us and our Planet? (Dr. John Fagan Professor of Molecular Biology, Maharishi University of Management; President, Genetic ID).

“When genetic engineers disregard the reproductive boundaries set in place by natural law, they run the risk of destroying our genetic encyclopedia, compromising the richness of our natural biodiversity and creating ‘genetic soup.’ What this means for the future of our ecosystem, no one knows”(Dr. John S. Hagelin Professor of Physics, Maharishi University of Management Presidential Candidate, The Natural Law Party).

“The fact is, it is virtually impossible to even conceive of a testing procedure to assess the health effects of genetically engineered foods when introduced into the food chain, nor is there any valid nutritional or public interest reason for their introduction”(Dr. Richard Lacey Professor of Food Safety, Leeds University, UK).

“Genetic engineering bypasses conventional breeding by using artificially constructed parasitic genetic elements, including viruses, as vectors to carry and smuggle genes into cells. Once inside cells, these vectors slot themselves into the host genome. The insertion of foreign genes into the host genome has long been known to have many harmful and fatal effects including cancer of the organism” (Professor Mae Wan-Ho Department of Biology, Open University, UK).

“In 1983, hundreds of people in Spain died after consuming adulterated rapeseed oil. This adulterated rapeseed oil was not toxic to rats.” Dr. Parke warns that current testing procedures for genetically altered foods including rodent tests do not prove safety for humans. He has suggested a moratorium on the release of genetically engineered organisms, foods, and medicines (Professor Dennis Parke School of Biological Sciences, University of Surrey, UK).

“Genes encode proteins involved in the control of virtually all biological processes. By transferring genes across species barriers which have existed for aeons between species like humans and sheep we risk breaching natural thresholds against unexpected biological processes. For example, an incorrectly folded form of an ordinary cellular protein can under certain circumstances be replicative and give rise to infectious neurological disease” (Dr. Peter Wills Auckland University, New Zealand).

“Probably the greatest threat from genetically altered crops is the insertion of modified virus and insect virus genes into crops. It has been shown in the laboratory that genetic recombination will create highly virulent new viruses from such constructions. Certainly the widely used cauliflower mosaic virus is a potentially dangerous gene. It is a para-retrovirus meaning that it multiplies by making DNA from RNA messages. It is very similar to the Hepatitis B virus and related to HIV. Modified viruses could cause famine by destroying crops or cause human and animal diseases of tremendous power” (Dr. Joseph Cummins Professor Emeritus of Genetics, University of Western Ontario).

“We see this as a multi-million dollar problem. In Europe, there is already a big problem with gene flow between wild beet and cultivated beet. Oil-seed rape (canola) also has close relatives and is going to cause problems in the future. One would expect that the kind of genes that are now being engineered are going to be the ones that have a higher potentiality for causing trouble” (Dr. Norman Ellstrand Professor of Genetics, University of California).

“The generation of genetically engineered plants and animals involves the random integration of artificial combinations of genetic material from unrelated species into the DNA of the host organism. This procedure results in disruption of the genetic blueprint of the organism with totally unpredictable consequences. The unexpected production of toxic substances has now been observed in genetically engineered bacteria, yeast, plants, and animals with the problem remaining undetected until a major health hazard has arisen. Moreover, genetically engineered food or enzymatic food processing agents may produce an immediate effect or it could take years for full toxicity to come to light” (Dr. Michael Antoniou Senior Lecturer in Molecular Pathology, London, UK).

“Recombinant DNA technology faces our society with problems unprecedented not only in the history of science, but of life on the Earth.  It places in human hands the capacity to redesign living organisms, the products of some three billion years of evolution”.

“Such intervention must not be confused with previous intrusions upon the natural order of living organisms; animal and plant breeding, for example; or the artificial induction of mutations, as with X-rays. All such earlier procedures worked within single or closely related species. The nub of the new technology is to move genes back and forth, not only across species lines, but across any boundaries that now divide living organisms. The reports will be essentially new organisms, self-perpetuating and hence permanent. Once created, they cannot be recalled”.

“Up to now, living organisms have evolved very slowly, and new forms have had plenty of time to settle in. Now whole proteins will be transposed overnight into wholly new associations, with consequences no one can foretell, either for the host organism, or their neighbors.”

“It is all too big and is happening too fast. So this, the central problem, remains almost unconsidered. It presents probably the largest ethical problem that science has ever had to face. Our morality up to now has been to go ahead without restriction to learn all that we can about nature. Restructuring nature was not part of the bargain. For going ahead in this direction may be not only unwise, but dangerous. Potentially, it could breed new animal and plant diseases, new sources of cancer, novel epidemics”.

The truth is that some scientists are wholeheartedly against genetic engineering and some are wholeheartedly for it. In this situation the only scientific solution is to foster public scientific debate and to delay application until all fundamental questions are resolved. Corporations, however, have a vested interest in speedy application. They are not willing to wait and are attempting to gather the support of the public through extensive marketing campaigns. But there is a vast discrepancy between biotech claims and the simple facts.

India’s rejection of the 1,000 tones food aid consignment from the United States comes at a time when the country is saddled with more than 51 million tones of food grains, much of it stacked in the open for want of adequate storage space. And yet, the US is trying desperately to arm-twist India into accepting the consignment of genetically modified food. Senator Christopher Bond was recently in India, trying to exert political pressure for lifting the ban.

What has not been reported is that the food consignment was actually part of an attempt by the US to dump unhealthy food onto unsuspecting societies all over the world. And that too as aid and relief consignments. What a clever and sophisticated way to dump rubbish all over the world.

Food analyst Devinder Sharma says that this is not the first time that what India is likely to receive from the US is unhealthy. In fact, all food consignments to India, including those under the PL-480 in the first three decades after India’s Independence in 1947, were of food stuff that was either ‘cattle feed’ or sub-standard. US have been trying to push in genetically modified soybean into India since the year 2000. Interestingly, when the US imports food from developing countries it uses the sanitary and phytosanitary standards to reject food containing even a fraction of the allergens or pathogens saying that it will be harmful for human consumption. But the soyabean that it has been trying to force on India comes with 15 diseases, seven of which are viral diseases. It also contains one dreaded nematode species, H.glycerine which is not reported from India and is known to travel with even seed samples. But then, the US is telling India that these diseases and pathogens are not harmful!!

It is also time the Indian government (as well as the international community, including the FAO) makes it mandatory for relief agencies to follow the example of World Food Program (WFP). This UN agency buys food stocks from India for distribution to the vulnerable groups within the country.

As India edges closer to what is probably the last year of field trials for Bt Brinjal before commercial approval may be granted, large scale resistance has been building up all over the country. Bt Brinjal, if allowed in India, would be the first food crop in the world with the Bt gene inserted into it that is to be directly consumed by human beings. Indians feel that they are about to be made guinea pigs by USAID, and by Monsanto and Cornell University that have developed this crop.

For the past six years, Indian farmers have experienced the stark realities of GM crop cultivation in the country in the form of Bt cotton. Reports continue to pour in from various districts of Andhra Pradesh including Adilabad, Warangal and Nalgonda on animal illnesses and deaths after grazing on Bt cotton fields. Farmers and shepherds have been reporting the toxic effects of Bt cotton on livestock since 2003. But the regulators continue to rubbish the reports. Farmers and workers experience allergic reactions during harvest of Bt cotton, with scores of victims in different states. However, the governments have not even begun to acknowledge that.

To make matters worse, the ecology of cotton pests has altered drastically and Bt cotton farmers are dealing with newer pests and diseases. Last season’s infestation of mealy bug, a sucking pest, has resulted in pesticides sales shooting up steeply in several states including Punjab.

For farmers who wish to remain GM-free or organic, they find it almost impossible to get non-GM seed. Hundreds of organic farmers are placing special orders directly with seed companies for non-transgenic seed, as it is not readily available from retailers.

It is at this juncture that farmers’ unions, consumer organizations, environmental groups, development organizations and concerned scientists have stepped up their protests against Bt Brinjal, realizing that the experience with Bt cotton cannot be allowed to be repeated, especially with a vegetable crop that is directly consumed by people.

A large informal network called “Coalition for GM Free India” was formed in 2006, representing organizations and individuals from more than 15 states of India. The coalition has been active since then in raising awareness among civil society groups, media and the general public, and in creating an informed debate on GMOs. The Coalition also sees resistance to GM crops in a larger framework of democratization of policy-making in science and technology for the country. Members believe that farmers’ science and knowledge, especially with regard to ecological farming, is the only sustainable way forward for farming in India.

On 8 April 2008, farmers’ organizations and other civil society groups in different states undertook concerted direct actions to highlight the dangers of GM crops in general and Bt Brinjal in particular. They targeted the state governments, which have a constitutional responsibility and authority with regard to agriculture-related issues. This is a prelude to a national level protest in Delhi on 6 May 2008 where hundreds of concerned citizens – farmers and consumers – will join the protest from around 15 states. The day of action included many events countrywide.

In Andhra Pradesh, more than 250 people took part in a protest meeting in Hyderabad organized by the Coalition for GM-Free Andhra Pradesh and around 15 mothers with their children put out a “NO GM IN OUR FOOD” message. Farmers and consumers from nine districts of Andhra Pradesh attended the meeting, including those who suffered losses with Bt cotton, those who have experienced allergies while working in Bt cotton fields and others who have lost their livestock that grazed on Bt cotton. Scores of farmers who practice ecological farming also joined in, urging the AP government to ban GM crop trials in the state.

In Chittoor, the APVVU (an agricultural workers’ union) organized a rally in the district headquarters against GM crops.  Speaking to a delegation that presented him with a memorandum in the evening, the Minister for Agriculture in Andhra Pradesh, Mr. Raghuveera Reddy, assured the delegation that “if there is even 0.001 % problem with Bt Brinjal as per the University scientists, the government will proceed very cautiously on the matter.”

In Madhya Pradesh, around one thousand farmers took out a “death procession” of Bt Brinjal in Jhabua. In this symbolic protest, four pall-bearers joined by hundreds of farmers carried a large GM brinjal in a solemn Hindu cremation ritual; the protest was organized by Beej Swaraj Abhiyan (Seed Freedom Movement).

In Kerala, during a seminar organized by Thanal (an environmental organization), the state Agriculture Minister reiterated his stand against allowing any GM crop trials in the state of Kerala, which is a mega-biodiversity hotspot. He also signed an anti-GM banner to be displayed in Delhi on 6 May. The seminar noted that foods containing soy, canola, corn and cottonseed ingredients, imported from the US, were being sold in many supermarkets, posing health threats. Speakers in the seminar called upon the people to boycott soybeans, corn (maize) products and other GM foods.

In Orissa, the Coalition for GM-Free Orissa submitted a petition signed by more than 30, 000 farmers, intellectuals and activists in the state to the Minister for Agriculture. And rallies were held at Kendrapara, Bargarh, Bolangir, Rayagada, Sundargarh, Ganjam, Nayagarh and Sambalpur districts. Letters from 50 sarpanches (elected heads of local governance councils at the village level) were also submitted to the Minister asking him to ensure that Orissa remains free from genetically modified seeds.

The largest protest took place in Bhubaneswar, the state capital of Orissa, organized by Orissa Nari Samaj, a tribal women’s collective. More than 5, 000 tribal women from 54 blocks, along with hundreds of farmers from Dhenkanal and over 300 students from Bhubaneswar joined a large protest rally against GM crops. They exhibited 500 indigenous paddy varieties that they have collected in front of State Assembly to send their message to the state government that it will put the rich diversity of rice species at risk if GMOs entered the region.

They submitted a memorandum to the Chief Minister, urging him to declare Orissa a GE-Free, organic state. In Maharashtra, district level anti-GMO meetings were organized by the Sashwat Sheti Kriti Parishad to build farmer- and consumer awareness. The districts covered were Buldana, Amravati, Akola, Washim and Wardha.

In Tamil Nadu, CREATE and FEDCOT, consumer rights groups, organized a consumer awareness meeting in Tirunelveli on “GM Food & Consumer Health”. The meeting called for a ban on all GM foods in India.

On 14 April 2008, the day of Baisakhi (the new year’s day in certain states), protest and awareness meetings were again organized in Tamil Nadu and Punjab.

Ecological farming is the answer and not GM: The various events on and around 8 April are an indication of the growing mass resistance against GM crops and foods in India, and it is high time that the central and state governments took note of the concerns of farmers and consumers with regard to this technology being thrust down their throats in an undemocratic fashion.

This comes at a crucial time when ecological farming is spreading rapidly all over India, supported by civil society groups including those in the Coalition for GM-Free India. It should convince the government that safer and much more sustainable alternatives do exist, and there is really no need for GM crops in the country.

Sarita G. Bhat – SAFER ALTERNATIVES FOR A…

Sarita G. Bhat, Safer Alternatives for a Cleaner Environment, (Ed.) S.Jisha, B.Hari & T.K.Remesan, Proc. Nat. Sem. on Env. Biotech. Chall. and Oppor.,  Envirotech-2008, P.G. Dept. of Zoology, S.N.C. Natiika, pp 39-56.

(Microbial Genetics Laboratory, Department of Biotechnology, CUSAT, Cochin, e-mail: saritagbhat@gmail.com, sarit@cusat.ac.in)

Abstract

Pollution is defined as the introduction of any solid, liquid or gaseous substance in such concentration that may be or tend to be injurious to environment [Indian Environment (Protection) Act, 1986]; broadly classified as water, air, land, noise & radioactive pollution. Biotechnology can be used to solve pollution problems in two ways-The root cause is attacked by the introduction of biotechnological production methods/innovations  which are intrinsically less polluting, and the use of  microbes as voracious scavengers, which removes all kinds of pollutants. Biosubstitution holds the key, i.e. replacement of synthetic chemicals with biological alternatives, e.g. biofuel, bioplastic, biofertilizers, biopesticides.

Several industries benefit from the use of biotechnological alternatives and the impact on the environment is tremendous.  The chemical industry where the use of biocatalysts to produce novel compounds, reduces waste byproducts and improves chemical purity.  Decreasing the use of petroleum for plastic production by making “green plastics” from renewable crops such as corn or soybeans.  The Bioplastics or compostable biopolymer can be used to produce packaging materials, clothing and bedding products.  The price and performance are competitive with petroleum-based plastics and polyesters. Bio-feed stocks offer two environmental advantages over petroleum-based production: Production will be cleaner, in most cases, less waste will be generated and if the biomass source is agricultural refuse, the gains are double. In the paper industry by improving the manufacturing processes to include the use of enzymes, lowers the toxic byproducts from pulp processes.  In the textiles industry toxic byproducts of fabric dying and finishing processes are markedly lessened.  Fabric detergents are becoming more effective with the addition of enzymes to their active ingredients.  Enzymes are added to increase nutrient uptake in feeds and thereby decrease phosphate byproducts from the livestock industry.  The use of bio-fertilizers and bio-pesticides have also resulted in the reduced use of chemical pesticides and fertilizers, thereby also reducing the polluting effects of chemical pesticides and fertilizers.

To conclude, Industrial Biotechnology although in the early stages of development, is already providing several useful tools that allow for cleaner, more sustainable production methods and will continue to do so in the future. All this is only a pointer at the availability of safer alternatives which will pave the way for sustaining cleaner environments

Old Kashmiri saying….

We did not inherit this earth from our forefathers……

We are borrowing it from our children……..

Introduction

Human civilizations and their activities since time immemorial added to the earth’s environments, materials that can influence and affect the natural ecosystems, thereby leading to pollution of not only land, but also air and water systems, in turn affecting health and quality of life.   Waste generation is a side effect of the consumption and production activities from domestic and industrial activities, e.g. sewage, waste waters from food and other industries, wood and agricultural wastes, toxic industrial wastes and other byproducts.

Pollution is defined in different ways –”contamination of the earth’s environment with materials that interfere with human health, the quality of life, or the natural functioning of ecosystems” (Encarta.com); wrong substances in a wrong quantity in the wrong time and at the wrong place; agent which causes imbalances in the earth’s ecological equilibrium. The Indian Environment (Protection) Act, 1986, defines pollution as ‘Introduction of any solid, liquid or gaseous substance in such concentration that may be or tend to be injurious to environment’.

Urbanization and industrial developments have led to public concerns over the state of the environment.  The major environmental problems posing a serious threat include solid waste disposal, waste water management, corrosion, fouling, deforestation, and pollution due to xenobiotics, heavy metals, toxic chemicals, industrial emissions, automobile emissions, oil spills, faecal coliforms, viruses and other contagious microorganisms, among others. Much attention is therefore given to improve the environment for future generations and in developed nations major environmental legislations are directed towards achieving this.

Role of Biotechnology in Pollution control?

The application of life sciences in conventional manufacturing is white biotechnology or industrial biotechnology.  It uses genetically engineered bacteria, yeasts and plants, whole cell systems or enzymes.   In most cases this results in lower production costs, less pollution and in resource conservation.

As the problems of pollution escalate day by day, physical and chemical methods of pollution control has proved inefficient.    Biotechnology is now being considered for newer methods of environmental protection.  Biotechnology can help solve pollution problems in two ways-The root cause is attacked by the introduction of biotechnological production methods which are intrinsically less polluting and by the use of microbes as voracious scavengers, which can help remove all kinds of pollutants.  Thus environmental biotechnology involves the efficient use of microorganisms, which due to their versatility and adaptability have always acted as environmental cleaners and the development of techniques and processes, whereby this potential can be used appropriately.

Biotechnology promises among other things-development of  modified bacteria by genetic engineering to clean oil spills, other pollutants like pesticides, in biodegradation of plastics, polymers and synthetic materials, biosensors and bio-monitors, treatment of municipal sewage & industrial effluent, indicators of pollution, prevention of communicable diseases through vector control; enhancement of oil recovery, control of microbial corrosion and leaching processes.  Biosubstitution holds the key, i.e. replacement of synthetic chemicals with biological alternatives, e.g. biofuel,  bioplastics,  biofertilizers,  biopesticides to name a few .

Air pollution abatement: The major air pollutants, termed the ‘gang of four’ are sulphur dioxide, nitrogen oxides, volatile compounds and particulates.  Air pollution is generally detected by the foul odour caused by organic molecules. Biological gas purification systems in use may be either bioscrubbers, biofilters or biotrickling filters.

A typical bioscrubber consists of an absorption column and one or more bioreactors, in which biological oxidation takes place. The bioscrubber may be ‘wet’ or ‘dry’. In ‘wet’ bioscrubber, there is a packed bed with counter current flow of liquid (often sewage) and gas (contaminated air).  Odorous compounds are transferred to the liquid phase and oxidized by the biofilm flora. The advantages of ‘wet’ bioscrubbers are the high scrubbing efficiency due to enhanced rate of mass transfer, reduced volume of liquid required and the absence of the ultimate effluent disposal problem. In ‘dry’ reactors, the beds are packed with biologically active, sorptive material like peat or compost, and the contaminated gases are clown upwards through the bed.

Biofilters function on the ability of microbes to oxides volatile organic compounds.  They may be of the open or closed type and contain soil, compost peat, heather or bark, used in combination in biobeds.  The essential requirements are uniformity and permeability of the biobeds, sufficient space , turning 3 to 4 times a year and proper drainage.

In biotrickling filters, the gases are passed through the biofilter packaging, through which water trickles down, dissolving the gas without forming acids.

Some microbes have been observed to degrade specific air pollutants. Pseudomonas sp. and genetically engineered E. coli degrade trichloroethylene (TCE).  Thiobacillus ferroxidans gives solid sulphur from hydrogen sulphide and sulphur dioxide.  Volatile organic compounds are degraded and the products are carbon dioxide, water, biomass and inorganic salts.

Pre-treatment of fuels to reduce air pollutants are being considered. Bioprocessing of coal to remove undesirable contaminants like sulphur, nitrogen and trace metals; coal conversion by microbial liquefaction, solubilisation, gasification and pretreatment.

Water pollution abatement: Some of the pollutants in waste waters are suspended solids and insoluble organic compounds, which decompose and cause oxygen depletion and produce noxious gases.  By treatment they give CO2, CO, NH3, CH4, H2S, etc.  Heavy metals, cyanides and other toxic organics which are deleterious to aquatic life.  Heavy metals have been conventionally removed by adsorption onto polysaccharide and this may be modified for use in the activated sludge process. Bioremediation can be used for complex toxins.

Undesirable levels of nitrogen and phosphorous lead to eutrophication.    Nitrates may be removed by microbial nitrification and denitrification; under anoxic conditions, and in the presence of a carbon source (E.g. methanol), or using immobilized enzymes.  Phosphorous may be removed using surface –active agents. e.g. bio surfactants from Nocardia erythropolis.

Non-biodegradable chemicals and volatile materials like H2S and SO2.

Effluent treatment systems broadly fall into two categories-aerobic and anaerobic treatment systems.  Generally activated sludge and fixed film systems of different types are used for industrial effluent treatments.

Aerobic treatment systems: Activated sludge process operates as a homogenous continuous culture and is aerated.  Organic matter is rapidly removed by biosorption and flocculation and more slowly by oxidation and biosynthesis.  The floc settles in a secondary sedimentation tank and may be used as a inoculums.  BOD and suspended solids are reduced by 85-95%.  Macro-invertebrates (flies), fungi, nematodes and rotifers are less dominant, while protozoan are abundant in activated sludge.  Various modifications of the activated sludge- tapered aeration, step aeration, contact stabilization and advanced activated sludge which operates with pure oxygen, to name a few, have been developed to overcome the high running costs, difficulty in operation and maintenance and the production of large surplus biomass.

Biological filters-fixed film systems where the microbes are attached to an inert supporting medium packed in a tank or tower, with an even distribution of effluent and introduction of air from the bottom vents.  A variation is the rotating biological contactors, where the fixed film of microorganisms grows on discs on a rotating shaft.  Microbial slime develops on the support using the organic matter and oxygen, and is sloughed off whn the thickness increases and collected as sludge in a sedimentation tank.  The common organisms present are facultative bacteria like Achromobacter, Flavobacterium, Pseudomonas, Alcaligenes,filamentous forms like the Sphaerotilus natans, Beggiatoa and at lower levels nitrifiers like Nitrosomonas and Nitrobacter and a few fungi, algae and protozoans.

Anaerobic treatments systems: Anaerobic digestion is a microbial fermentation process where the organic matter is converted into CO2 and CH4 in the absence of high levels of nitrates and sulphates.   It is used for sludge digestion and stabilization in sewage treatments. Anaerobic contact digesters, packed bed reactors, upflow anaerobic sludge digesters, membrane bioreactors are some of the anaerobic treatment systems in use.  Very low sludge production, lower energy consumption, CH4 production, operation at a high organic loading rate and absence of odour and aerosol formation are some of the advantages over the aerobic processes.

Anaerobic contact digesters are the equivalents of the activated sludge process, with a completely stirred tank under anaerobic conditions and a portion of the settled sludge returned to the digester.  The sludge is concentrated and has a longer retention time, enabling retaining of the methanogenic organisms.  These are used for the treating effluents from the sugar processing units, distilleries, citric acid and yeast production, farm slurries, etc.  A disadvantage is the poor settlement of solids because of their attachments by the producer gas.

In packed bed reactors, the organism are enclosed in polystyrene spheres or filters (sand, silica, anthracite coal) in an enclosed vessel and liquid wastes flow upwards, preventing slime formation and sloughing of high concentration of the suspended solids.  The treatment rate is directly related to surface area of packing

In UASB, active bacteria are retained in the digester tank as high –density granular sludge in spite of gassing and upflow of the effluent. Initial inoculums of 10-15% granular sludge are required. Successful granule formation depends on the digester hydrodynamics and elements like Ca, P, Mg and NH3, Al and Si in the feed substrate and a large population of filamentous microorganisms (Methanothrix spp.).  Calcium chloride addition prevents the toxicity due to long chain fatty acids and helps granulation.

Membrane bioreactors remove the inhibitory effects of biodegradable pollutants such as volatile organic compounds and prevent the direct contact between aerating gas and waste water.  The effluents pass through the membrane to reach the biofilm for degradation.

Immobilized biocatalysts is one whose movement in space is completely aor partially restricted. They form a distinct phase within the bulk phase in which the substrate, effector, inhibitor molecules are dispersed and their exchange is possible.  Immobilized biocatalysts used in four categories of applications in waste water treatments viz.BOD/COD reduction, specific pollutants detoxification, as biosensors (e.g. CH4biosensor) and for bioconversion of waste to get specific products

Solid wastes generated as a result of waste treatment systems processes can be treated with acid and reabsorbed on special polymers which interact with the contaminant metals to give materials analogous to low grade ore, this may be processed to give metallic elements.  Recalcitrant or toxic organic compounds require specially adapted or genetically modified microorganisms or consortia of microbes for their degradation.  Domestic refuse generally goes into landfills, but may be reclaimed as biogas.  Sewage sludge, domestic refuse and agricultural wastes can be used in compost production. Biomass cultivation using waste waters is another option being explored; it is the production of specific types of biomass, by photosynthesis, coupled to the removal of plant nutrients like nitrogen and phosphorous from the water.

Land pollution abatement: Contamination of land is contributed to by landfills, dumping or accidental spillage, accumulation of building residues, rubble, chemical fertilizers and pesticides, with the net result being an increase in organic ions and a decrease in organic matter in the soil.  Some methods of alleviating this problem are the use of polymers for absorption and slow release of contaminating elements necessary as plant nutrients and the use of microorganisms for bioremediation and biodegradation.

Two approaches are normally used for bioremediation of polluted soils- In-situ operation, where the polluted zone or compartment is subject to restoration and Ex-situ operation, where the contaminated isolated volume is subjected to treatment and restored to its site.  Biological treatments can be initiated by biostimulation makes use of the existing organisms by providing favourable conditions for their action, viz. Adjusting nutrients, pH, temperature, growth factors; bioaugmentation involves the external introduction the selected strains of microbes with specific degradative capacities to improve the process of biodegradation. The introduced microorganism should remain viable and compete with the indigenous flora.

White biotechnology: White biotechnology alludes to industrial and environmental biotechnology, which is a broad and expanding area that includes manufacture of enzyme for various industrial applications, manufacture of biofuels, bioplastics, biofertilizer and biopesticides, bioleaching using bacteria, to the applications of microbes for pollution abatement by a process called as bioremediation.

Several industries benefit from the use of biotechnological alternatives and the impact on the environment is tremendous.  The chemical industry where the use of biocatalysts to produce novel compounds, reduces waste byproducts and improves chemical purity; Decreasing the use of petroleum for plastic production by making “green plastics” from renewable crops such as corn or soybeans.  The bioplastics or compostable biopolymer can be used to produce packaging materials, clothing and bedding products.  The price and performance are competitive with petroleum-based plastics and polyesters. Bio-feed stocks offer two environmental advantages over petroleum-based production: Production will be cleaner, in most cases, less waste will be generated and if the biomass source is agricultural refuse, the gains are double. In the paper industry by improving the manufacturing processes to include the use of enzymes, lowers the toxic byproducts from pulp processes.  In the textiles industry toxic byproducts of fabric dying and finishing processes are markedly lessened.  Fabric detergents are becoming more effective with the addition of enzymes to their active ingredients.  Enzymes are added to increase nutrient uptake in feeds and thereby decrease phosphate byproducts from the livestock industry.  The use of bio-fertilizers and bio-pesticides have also resulted in the reduced use of chemical pesticides and fertilizers, thereby also reducing the polluting effects of chemical pesticides and fertilizers.

Biofuels: It is already acknowledged that the economies the world over have to prepare for an era when fossil fuel availability will come to an end. Governments are pushing towards the alternatives through subsidies and regulations.  Biofuel production is a part of industrial biotechnology and ethanol is a biofuel currently produced from fermentation of cane sugar.  Plants and agricultural wastes are rich in cellulose, a polymer of glucose, which is difficult to hydrolyze.  The search for efficient cellulases which can break down cellulose and make available glucose for ethanol production is a promise which has been kept.

Brazil is the first largest producer of ethanol –produced 15 billion litres annually (2003) and has the largest proportion of cars using a mixture of gasoline and 20 percent ethanol.  Even in the USA, a tenth of the motor fuel sold is a blend of 90 percent petrol and 10 percent ethanol.   The goal is to seek energy independence.  The USA, for instance has subsidies for making ethanol from maize kernels.  The American market for biofuels is about 7-8 billion liters per year.  The EU has set the target for 9 million tons of ethanol to be produced annually in Europe by 2010.   World over several countries are in the forefront to increase their biofuel production. (Economist, 2004a)

Companies like Maxygen, whose plant- biotech subsidiary, Verdia is trying to develop cellulose, that the plant cell will make in its own cell wall, but without digesting itself.  Royal Dutch Shell and Iogen, a Canadian Company has used a efficient cellulase enzyme technology that allows conversion of crop residues (stems, leaves and hulls) to ethanol, in their biofuel refinery. (Economist, 2003)

Although the cost of fossil fuels production is less than that of biofuels, it does not take into consideration the cumulative costs of shore and sea contamination by oil dredging, oil spills nor does it take into account the conflicts due to oil exploitation.  Biofuels on the other hand have a positive effect on tax recovery, self reliability and could also help the car manufacturers to meet their commitment on reducing carbon dioxide emissions.  This also allows for greater domestic energy production and it uses a renewable feedstock.
Other development in the oil sector is the use of enzymes.  Oil well drilling uses “muds” to lubricate the drilling string and to coat the insides of a bore hole with a layer of “cake”.  After a well is drilled, the cake must be removed or “broken”.  Traditional breakers are strong acids or other harsh chemicals. Enzyme breakers were developed especially for advanced horizontal drilling procedures. (BP Exploration)Advantages of enzyme breakers are high specificity, lower risk of formation damage, even degradation of filter cake, and using enzymes reduces acids or petro chemicals in water/mud discharge.

Bioplastics: Plastic are synthetic polymers which are not biodegradable.   Polymers such as polyethylene and polypropylene persist in the environment for many years after their disposal.   Physical recycling of plastics soiled by food and other biological substances is often impractical and undesirable.   Fossil fuels (oil, gas, coal) are in finite supply and alternative renewable sources of raw materials are needed.

Biopolymers are obtained via polymerization of biobased raw materials through engineered industrial processes. The raw materials of biopolymers are either isolated from plants and animals or synthesized from biomass using enzymes/ microorganisms.  Storage compound of most bacteria is polyhydroxybutyrate.

Why biopolymers? Biopolymers have several advantages and applications-Biopolymers derived from microbes and plants bind metals strongly, they can be used as adsorbents for hazardous metals and strategically important metals and have excellent selectivity for certain metals. Biopolymers can be also be used in metal recovery processes like precipitation, electro winning and ion exchange.  They find application in coatings, fibers, plastics, adhesives, cosmetics, oil Industry, paper, Textiles/clothing, water treatment,biomedical, pharmaceutical, and automotive industry. In addition production cost is low under mild process conditions. Examples of biopolymers-polyesters-polylactic acid, polyhydroxyalkanoates; proteins-silk, soy protein, corn protein (zein), polysaccharides-xanthan, gellan, cellulose, starch, chitin, polyphenols , lignin, tannin, humic acid; Lipids-waxes, surfactants; specialty polymers- shellac, natural rubber, nylon (from castor oil).   USDA’s Bioproduct Chemistry & Engineering Research Unit focuses on creating new polymer technologies in which underutilized components of crops and their residues are processed into value-added biobased products.

Biodegradable polymers break down in a bioactive environment to natural substances by enzymatic processes and/or hydrolysis.  Where is Biodegradable Polymers Needed? Packaging materials (e.g., trash bags, loose-fill foam, and food containers), Consumer goods (e.g., egg cartons, razor handles, toys), Medical applications (e.g., drug delivery systems, sutures, bandages, orthopedic implants), cosmetics, coatings and hygiene products.  Global consumption of biodegradable polymers increased from 14 million kg (30.8 million lbs) in 1996 to 68 million kg (149.6 million lbs) in 2001. U.S. demand for biopolymers is expected to reach $600 million by 2005 according to a Fredonia Group study

Opportunities for Biodegradable Polymers: Oil-modified polyesters (alkyds) are synthesized by reacting oils, polyhydric alcohols, and polyfunctional acids. Single largest quantity of solvent-soluble polymers manufactured for use in surface coatings industry. Long chain fatty acid dimers derived from vegetable oils are reacted with slight excess of primary amines to synthesize polyamides.

Epoxidized oils are synthesized by reacting vegetable oils (typically soybean and linseed oils) with peracids or hydrogen peroxide.   Epoxidized oils are employed as plasticizers for polyvinyl chloride and as high temperature lubricants.

As early as 1973, it was shown that poly (e-caprolactone) degrades in bioactive environments such as soil.  Poly (e-caprolactone) and related polyesters are water resistant and can be melt-extruded into sheets and bottles.

Polyhydroxyalkanoates (PHA) accumulate as granules within cell cytoplasm. PHAs are thermoplastic polyesters with  m.p. 50–180ºC (BiopolTM).Properties can be tailored to resemble elastic rubber (long side chains) or hard crystalline plastic (short side chains).  Polyhydroxybutyrate (PHB)– polyhydroxyvalerate (PHB-V) is formed when bacteria is fed a precise combination of glucose and propionic acid and has properties similar to polyethylene but degrades into water and carbon dioxide under aerobic conditions.  ~75% of industrial corn starch is made into adhesives for use in the paper industry.  Corn starch absorbs up to 1,000 times its weight in moisture and is used in diapers (>200 million lb annually).  Starch-plastic blends are used in packaging and garbage bag applications.  Starch blended or grafted with biodegradable polymers such as polycaprolactone are available in the form of films.  Blends with more than 85% starch are used as foams in lieu of polystyrene.

Cotton contains 90% cellulose while wood contains 50% cellulose.  Cellulose derivatives are employed in a variety of applications.  Carboxymethyl cellulose is used in coatings, detergents, food, toothpaste, adhesives, and cosmetics applications.  Hydroxyethyl cellulose and its derivatives are used as thickeners in coatings and drilling fluids.  Methyl cellulose is used in foods, adhesives, and cosmetics.  Cellulose acetate is a plastic employed in packaging, fabrics, and pressure-sensitive tapes.

Chitin, a polysaccharide, is almost as common as cellulose in nature, and is an important structural component of the exoskeleton of insects and shellfish.  Chitin and its derivative, chitosan, possess high strength, biodegradability, and nontoxicity.  The principal source of chitin is shellfish waste.

Chitosan forms a tough, water-absorbent, oxygen permeable, biocompatible films, and is used in bandages and sutures. It is used in cosmetics and for drug delivery in cancer chemotherapy.  Chitosan carries a positive charge (cationic) in aqueous solution and is used as a flocculating agent to purify drinking water.

Lactic acid is produced principally via microbial fermentation of sugar feedstocks.   Variation in polymerization conditions and L- to D- isomer ratios permit the synthesis of various grades of polylactic acid.  Polylactide polymers are the most widely used biodegradable polyesters -Cargill-Dow, USA.  PLA is compostable, is carbon neutral – CO2is recycled and can replace PET, polyesters and polystyrene.  Polylactic acid (PLA) degrades primarily by hydrolysis and not microbial attack.  PLA fabrics have a silky feel and good moisture management properties (draws moisture away and keeps the wearer comfortable). Copolymers of lactic acid and glycolic acid are used in sutures, controlled drug release, and as prostheses in orthopedic surgery.   In the future, PLA will be made from ligno-cellulosic biomass.

Polyamino acids (polypeptides) are found in naturally occurring proteins.   20 amino acids form the building blocks of a variety of polymers.  Combination of these amino acids in different ratios permits the development of copolymers with varying rates of biodegradability (for use as drug delivery systems).   Polypeptides based on glutamic acid, aspartic acid, leucine, and valine are the most frequently used.  Amino acid polymers are particularly attractive for medical applications since they are nonimmunogenic (i.e., do not produce any immune response in animals)

Polyvinyl alcohol is the only polymer with exclusively carbon atoms in the main chain that is regarded as biodegradable.   Polyvinyl alcohol is used in textile, paper, and packaging industries.

Sorona® is a biopolyester marketed by DuPont for use in fibers and fabrics and is based on 1, 3-propanediol (derived from fermentation of corn sugar).   Sorona® offers advantages over both nylon and PET by virtue of softer feel, better dyeability, excellent wash fastness, and UV resistance.

Biopesticides: The biopesticide market worldwide amounts to ~150million Euro. They are also known as BCAs or Biological control agents. Biochemical pesticides are naturally occurring substances that control pests by non-toxic mechanisms.  Conventional pesticides, by contrast, are generally synthetic materials that directly kill or inactivate the pest.  Biochemical pesticides include substances, such as insect sex pheromones that interfere with mating as well as various scented plant extracts that attract insect pests to traps.  They suppress pests by: producing a toxin specific to the pest, causing a disease or by preventing establishment of other microorganisms through competition.   Biopesticides have a narrow target range and a very specific mode of action, are slow acting, have relatively critical application times, suppress, rather than eliminate a pest population, have limited field persistence and a short shelf life; are safer to humans and the environment than conventional pesticides and present no residue problems.

The bacterium Bacillus thuringiensis (Bt) occurs naturally in soil. Insecticidal strains, discovered in 1911, have been used for pest control since the 1950s.  They produce a δ-endotoxins, proteins that are toxic to insects but harmless to humans.   Green biotechnology has improved the efficiency of this principle by introducing the gene for the δ-endotoxins into the various agricultural crops by using recombinant DNA technology, turning them resistant to insect infestations.  In the 1990s, INGARD ® cottons containing a Bt protein toxic to them were released, resulting in a substantial reduction in insecticide use where they are grown.

Also several living fungi, insect viruses and even parasitic worms are employed as a selective insecticide as they very aggressively infect insects, eventually killing them.  These preparations are prepared by fermentation processes and are sprayed on fields and forests.   Fungus Beauveria bassiana (B.b.) is cultured in the laboratory and the spores (conidia) are harvested.   The spore powder is then formulated in a natural carrier with emulsifiers and other adjuvants and packaged as a liquid for application.

Green Guard® is an attractive alternative for locust control in Australia because of the absence of environmental effects especially on aquatic organisms and birds and it leaves no residues in meat or crops.  It can be used in organic beef areas and other areas where the use of chemical pesticides is undesirable.  The disease takes 10-14 days to kill a locust and thus is used more for preventative control on organic properties and in environmentally sensitive areas rather than for prevention of crop damage. Its cost is comparable with that of chemical insecticides.

Around the world, diamondback moth (DBM), Plutella xylostella, is a major threat to those much loved vegetables, brassicas (cabbages, cauliflowers and other related greens). It is attacked by the fungus, Zoopthora radicans, but too late in the season to help growers.

In a novel approach, the insects themselves will be used to spread the fungal spores to other DBM earlier in the season than when the natural outbreaks would occur.  Male moths, attracted to inoculation stations by pheromones (sex attractants), will pick up the fungal spores and then spread them through the DBM population.  This ‘auto-dissemination’, has advantages over chemical insecticides, both in terms of environmental and economic sustainability and avoidance of resistance problems. This is particularly important because of the advantages that ‘clean and green’ produce confers upon our export and domestic markets.  The research is being done in collaboration with researchers in several European Union nations, Cuba and Mexico.

Bio-herbicides are also in the market.  Several phytopathogenic fungi have found application in this area.  Spores of Colletotrichum gleosporioide (COLLEGOTM) are used against vetch in rice and soya bean cultures; Phytothora palmivora (DEVINETM) against chocking weed in citrus cultures in the USA.

Bioleaching: In Zinc refining, in old process – finishing wastewater contains heavy metals, sulphuric acid and gypsum used to precipitate sulphates.  Budel Zinc, Netherlands, uses a new biological process was developed using sulphate reducing bacterial enzymes for sulphate reduction.  This process allows zinc and sulphate to be converted to zinc sulphide which can then be recycled to the refinery.  As a result, no gypsum is produced, water quality has been improved and valuable zinc is recycled.

Copper smelters are generally heavy polluters.   Bacteria can be used in leaching metals from ores. This also allows treatment of low-grade ores or concentrates containing problem elements like arsenic.  Biological leaching produces environmental benefits, lowers environmental emissions and costs. Reduces generation of particulate emissions (dust).  Using bacteria reduces sulphur dioxide emissions.  Allows safe handling of arsenic impurities in a stable form.   Chile is the world’s largest producer of copper. BioSigma S.A, a Chilean company, intends to develop technologies, involving the identification of microorganisms, production of their biomass and the identification of the specific genes involved in facilitating the bioleaching of copper ores.

Other advances

Production of Antibiotic -7 amino-cephalosporin) (Biochemie, Germany)

• Converted chemical synthesis to biological process.
• Old chemical route – used chlorinated solvents, hazardous chemicals.
• Biological process – no toxic ingredients.
• Reduced air, water and land pollution discharges

Manufacture of Vitamin B2 (Hoffman La-Roche, Germany)

• Substituted multi-step chemical process with a one-step biological process using a genetically modified organism.
• Land disposal of hazardous waste greatly reduced.
• Waste to water discharge reduced 66%.Air emissions reduced 50%.Costs reduced by 50%

Production of Antibiotic -Cephalexin (DSM, Netherlands)

• Involved conversion from chemical synthesis to biological synthesis.
• Old process produced 30-40kg of waste per 1kg of product.
• New one step biological process–eliminated the need to use methylene chloride.
• Dramatically reduced waste generation and toxic emissions.

Production of Acrylamide (Mitsubishi Rayon, Japan)

• Conversion to enzymatic process reduced levels of all waste products as a result of high selectivity of enzymatic reaction.
• Lower energy consumption for enzymatic process,1.9 MJ/kg for old process – 0.4 MJ/kg for new process.
• Enzymatic process produced lower CO2 Emissions-old process – 1.5 kg CO2/kg product; enzyme process 0.3 kg CO2/kg product.

Synthesis of Polyester Adhesives (Baxenden, Untied Kingdom)

• Chemical process used tin or titanium catalyst at 200oC.
• New enzyme process more energy efficient.
• New process eliminated the need to use organic solvents and inorganic acids.
• Environmental improvements were realized along with improved product quality.

Wood Pulp Brightening (Domtar, Canada)

Wood pulp digestion is followed by bleaching in a multi-stage process to yield bright, strong pulp. Two options to reduce chlorine

1) Reduce lignin prior to bleaching (enzymes still in R&D)

2) Change bleaching chemistry

Enzyme xylanase produced third option – “activating” lignin so less bleach is needed. Xylanase treatment reduces the use of bleaching chemicals by 10-15% and reduces toxic dioxin formation

Vegetable Oil Degumming (Cerol, Germany)

• Enzymatic degumming of vegetable oils reduced amounts of caustic soda, phosphoric acid and sulfuric acid used compared to conventional processes.
• Enzymatic process reduced the amount of water needed in washing and as dilution water.Sludge production was reduced by a factor of 8.

Removal of Textile Finishing Bleach Residues (Windel, Germany)

• Hydrogen peroxide used for bleaching textiles usually requires several rinsingcycles.
• New enzyme process — only one high temperature rinse is needed to remove bleach residues.
• Reduced production costs, reduced energy consumption by 14%, reduced water consumption by 18%.

Wood pulp process (Leykam, Austria)

In traditional pulping – wood chips are boiled in a chemical solution to yield pulp. Biopulping (treatment of woodchips with a fungus) uses enzymes to selectivity degrade lignin and to break down wood cell walls. If next step is mechanical treatment, result is 30-40% reduction in energy inputs. If next step is chemical treatment, result is 30% more lignin being removed and lower amounts of chlorine bleach used. Cost reduction due to savings on energy and chemical costs.

Industries that benefit: The chemical industry -Using biocatalysts to produce novel compounds, reduce waste byproducts and improve chemical purity.
The plastics industry: Decreasing the use of petroleum for plastic production by making “green plastics” from renewable crops such as corn or soybeans.

The paper industry: Improving manufacturing processes, including the use of enzymes to lower toxic byproducts from pulp processes.

The textiles industry: Lessening toxic byproducts of fabric dying and finishing processes. Fabric detergents are becoming more effective with the addition of enzymes to their active ingredients.

The food industry: Improving baking processes, fermentation-derived preservatives and analysis techniques for food safety. The livestock industry: Adding enzymes to increase nutrient uptake and decrease phosphate byproducts.

The energy industry: using enzymes to manufacture cleaner biofuels from agricultural wastes

Conclusions

Industrial Biotechnology is in the early stages of development. It is already providing useful tools that allow for cleaner, more sustainable production methods and will continue to do so in the future.

References

Albert Sasson (2005). Industrial and environmental biotechnology- achievements, prospects and perceptions, UNU-IAS Report.

Anon (1998). Biotechnology for Clean Industrial Products and Processes (OECD, 1998).

Anon (2001). The Application of Biotechnology to Industrial Sustainability” (OECD, 2001)www.oecd.org.

Anon (1998). Environmental  Biotechnology, Ed. Agarwal (1998). APH Publishing Corporation, New Delh, Biotechnology3rd Edition. Ed. John E.Smith. Cambridge University press.

AMUTHA ET AL., ANTIOXIDANT ENZYME ACTIVITY …

Amutha.C, Bupesh.G, and Subramanian.P, Antioxident  Enzyme Activity of Marine Green Mussel Perna viridis During Different Seasons on Most and Least Polluted Areas along the South-East Coast of India, (Ed.) S.Jisha, B.Hari & T.K.Remesan, Proc. Nat. Sem. on Env. Biotech. Chall. and Oppor.,  Envirotech-2008, P.G. Dept. of Zoology, S.N.C. Natiika, pp1-79-88.

(Department of Animal Science, Bharathidasan University, Tiruchirappalli,  email: profsubbus@redifmail.com ; amuthaji@yahoo.co.in; bupeshgiri@gmail.com)

Abstract
Antioxidants are the innate or acquired molecules capable of slowing down or preventing the oxidation of other molecules, thus reduces the oxidative damage (damage due to reactive oxygen species) that caused by free radicals. The Rayapuram fishing harbour of Chennai (Station-1) is highly oil contaminated with oil sleeks on the surface. The relatively moderately oil contaminated area (Station-2) is about 2 km away from the fishing harbour and the least contaminated Vellar estuary Parangipettai (Station-3) was considered as the reference site. The two year (2005-2007) observation was recorded seasonally; the antioxidant activity varied seasonally and organally (digestive gland, gill and mantle) in the marine green mussel Perna viridis. The common antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR) activity were evaluated. The CAT and SOD are responded well with seasons (i.e. monsoon, pre-monsoon, post-monsoon and summer seasons). During monsoon period, both CAT and SOD activity are very low in all the stations, in both pre-monsoon and post-monsoon period their activity were moderate and higher enzyme activity was noted during summer season. On contrary, the GR activity was noted as very low during summer and very high during pre or post monsoon and the activity was moderate during monsoon period. In addition the GR activity responds to temperature also but the other antioxidants COT and SOD yielded no detectable activity. Among the organs liver showed higher COT and SOD activity when compared to gill and mantle but the GR exhibited the increased activity in gill but not in liver.
79

Introduction
Generally, Free-radicals are highly reactive chemicals that attack molecules by capturing electrons and thus modifying the chemical structures and also make it unstable. Leibfritz, et al., (2007) stated under normal physiological condition, animals maintained a balance between generation and neutralization of reactive oxygen species (ROS). However when organisms are subjected to xenobiotic compounds, rate of production of ROS in cells get increased along with hydrogen peroxide (H2O2), hypochlorous acid (HClO), and free radicals including hydroxyl radical (OH) and superoxide anion (O2.−). They are normally neutralized in the body employing the following enzymes.

Catalase are enzymes that catalyse the conversion of hydrogen peroxide to water and oxygen, using either an iron or manganese cofactor (Zamocky and Koller, 2004; Chelikani, 1999).

Superoxide dismutase (SOD) are a class of closely related enzymes that catalyse the breakdown of the superoxide anion into oxygen and hydrogen peroxide (Johnson and Giulivi, 2005; Grayck, et al., 2005). SOD enzymes are present in almost all aerobic cells and in extra cellular fluids.

Glutathione reductase is an enzyme which reduces glutathione disulphide (GSSG) to the sulfhydryl form GSH, which is an important cellular antioxidant (Meister, 1988 and Mannervi, 1987) For every mole of GSSG one mole of NADPH is required for reduction reaction. Where as in the cells exposed to high levels of oxidative stress (eg., red blood cells) need up to 10% of the available glucose for the production of the NADPH, in this reaction (Mannervi, 1987). The non enzymatic compounds like beta-carotene, lycopene, vitamins C, E, and A and some other substances also exerts antioxidant properties.

Mechanism: All organisms respire to survive, thus have their own cellular antioxidative defense system, involving both enzymatic as well as non-enzymatic components. Enzymatic pathway consists of SOD, CAT, GSH, GPX, etc. SOD dismutate the O2 ● − in to H2O2 which is reduced to water and molecular oxygen by CAT or is neutralized by GPX, that catalyzes the reduction of H2O2 to water and organic peroxide to alcohols using GSH as a source of reducing equivalent. Glutathione reductase (GSH) regenerated from oxidized glutathione (GSSG), which is a scavenger for ROS as well as a substrate of the other enzymes. GST conjugates xenobiotics with GSH for its excretion (Livingstone et.al., 1992; Arun and Subramanian, 1998; Halliwell, 1999).

Materials and methods
Experimental animal P.viridis collection and sample preparation protocols were given in the previous chapter. The S9 fractions were used for the evaluation of the following three antioxidant enzymes.
Antioxidant enzymes
Catalase: Catalase activity was assayed by the method of Caliborne (1985).

Results

Catalase
Catalase activity in P.viridis during different seasons: During the study period (2005-2007) the liver, foot and gill of P.viridis from the study stations were analyzed during different seasons such as summer (Apr-Jun), pre-monsoon (Jul- Sep), monsoon (Oct- Dec) and post-monsoon (Jan – Mar) periods. Among the season wise analysis of liver S9 fraction catalase activity was higher during summer season in all the stations (1st station, 114 ± 15.25 μmol / mg-1 protein/min-1, followed by 2nd station, 53.66±8.26 μmol / mg-1 protein/min-1 and 3rd station, 23±2.58 μmol / mg-1 protein/min-1 respectively). Where as the catalase activities were low during monsoon period [station-1, (65.13±10.59 μmol / mg-1 protein/min-1), station-2 (33.76±6.42 μmol / mg-1 protein/min-1) and station-3 (11±2.42 μmol / mg-1 protein/min-1) respectively]. The remaining seasons shows more or less equal catalase activity. The monsoonal minimum catalase activity ascends towards summer, then decline towards monsoon (Fig.1-3). Among the different organs analyzed higher activity was evident in liver (Fig-1) followed by foot (Fig.2) and gill (Fig.3). The seasonal pattern of enzyme activity was reflected in the organs (liver, foot and gill) analyzed also.

SOD activity in P.viridis during different seasons: The SOD activity showed a peak during summer and it descends to form a trough in monsoon, and then ascends towards summer. The observed higher activity during summer were, station -1 (86.82±11.36 Unit /mg-1 protein/min-1) followed by station-2 (36.43±5.25 Unit /mg-1 protein min-1) and then station-3 (13.21±2.24 Unit /mg-1 protein/min-1). On the other side very less activity were noted during monsoon period in station-1 (54.6±12.78 Unit /mg-1 protein/ min-1) followed by (14.56±6.72 Unit /mg-1 protein/min-1) in station-2 and (7±0.78 Unit /mg-1 protein/min-1) in station-3. Similarly the evaluated SOD activity in different organs also followed the trend of seasons. The higher enzyme activity was noted in liver (86.82±11.36 Unit /mg-1 protein/min-1) (Fig.4) followed by gill (54.23±7.12 Unit /mg-1 protein/min-1) (Fig.5) and the least in the foot (43.45±5.64 Unit /mg-1 protein/min-1) (Fig.6) during summer seasons, where as in the monsoon seasons the lowest values were recorded.

Glutathione reductase (GSH): Gulathione reductase activity behaves differently from the other two (catalase & SOD) antioxidant enzyme. Here the minimum level of GSH activity was noted in liver s9 fraction during both summer and monsoon seasons in all the three stations when compared to other seasons (Fig. 7). The highest level was observed during both post and premonsoon seasons in liver. The GSH activity during post monsoon in stations -1,2 & 3 were 68.45±10.36 μmol /mg-1 protein/ min-1, 36.78 ±6.22 μmol / mg-1 protein/min-1 and 5.67±1.21 μmol / mg-1 protein/min-1 respectively. The minimum activity recorded during summer in station-1 (27.36±6.98 μmol / mg-1 protein/min-1) followed by (12.72±6.72 μmol/ mg-1 protein/min-1) in station-2 and in station-3(2.12±0.32 μmol / mg-1 protein/min-1).

The higher level of GSH enzyme activity was noted in foot s9 fraction during post monsoon seasons at all stations [station-1 (39.86±8.12 μmol / mg-1 protein/min-1) station-2 (26.78±4.23 μmol / mg-1 protein/min-1) and station-3 (2.4±0.56 μmol / mg-1 protein/min-1)]. The lowest level of GSH activity was encountered in gill s9 fraction than the liver and foot (Fig.68). The higher level of GSH activity was recorded during Post monsoon in gill (Fig.69) in all the study sites [station-1(24.14±3.24 μmol / mg-1 protein/min-1) followed by station-2(14.44±2.13 μmol / mg-1 protein/min-1) and station- 3(1.89±09 μmol / mg-1 protein/min-1)].

Between the seasonal fluctuations, liver, foot and gill shown the elevated level of GSH in post monsoon subsequently declined in summer, then increased in premonsoon and falls in monsoon. Among all the station and all the seasons studied, the Rayapuram fishing harbour (Station-1) evidenced higher GSH activity when compare to other stations and very lesser activity in Parangipettai (Station-3).

Discussion

In the oxidative metabolism the role of antioxidants are very essential. The antioxidants are mainly divided into enzymatic and non enzymatic. Antioxidant requirements are mostly derived from the food sources. Present study gives emphasis the enzymatic antioxidants and thus evaluated the same in Perna viridis under environmental and experimental stress conditions. Interactions between abiotic and biotic factors are more common in the aquatic environments. Among abiotic factors, saline and thermal stress leads physiological disorder in animals, which primarily affects the metabolism, resulting in the accumulation of ROS (Rajagopal, et. al., 2005; Bhat and Desai, 1998). Thereby the season oriented three antioxidant enzyme activity was primarily observed in this study.

Catalase 4.1

The present study evidenced that the catalase activity was tissues specific and environmental parameter sensitive. The maximum catalase activity was recorded in the order of digestive glands (liver), foot and gill respectively. In the case of long (field during summer) term exposure to non-optimal salinity and temperatures affect the activity of scavenging enzyme catalase. Identical trend was demonstrated in the digestive gland, foot and gill tissues of zebra mussel (Parihar, 1997; Khessiba, et. al., 2005). The seasonal activity of catalase exhibit a summer hike and a monsoonal trough. It was coincide with the hydrocarbon pollutant level in that seasons (Correia et. al., 1996). It would reveal the ability of the animal to produce catalase was limited to its tolerance level then the production was contained in higher concentration of xenobiotics as well as longer duration (Sturve et. al., 2005).

Superoxide dismutase (SOD): SOD was designated as an index for a range of contaminants (Cossu, et al, 2000). The SOD exerts an elevated level in liver than foot and gill. Similar finding was reported in another species of bivalves, Scapharca inaequivalvis and Tapes philippinarum, (Santovito et.al., 2005; Lushchak et.al., 2006; Irato et. al., 2001). Further, who stated the experience of some species-specific differences that could be attributed to their different adaptation and habitat. In that the recorded high SOD activities in the gills of both the species may be related to their physiological role in respiration (Irato et. al., 2001). In the present study the SOD activity increased in liver during summer season and very minimum in monsoon period. It could be attributed to the higher hydrocarbon level in the summer and the minimum during monsoon due to washing off and higher dispersion / dilution in the season. The gill showed second place for the enzyme activity but foot exhibited very lower activity than other tissues. So liver is the ideal organ to evaluate the activity of SOD against the xenobiotics exposure. In the xenobiotics exposure profile SOD showed a positive correlation with catalase (r = 0.888, P < 0.05). SOD activity in the gills of H. fossilis on short-term temperature showed similar enhancement (Parihar, et. al., 1997; Zhang, et. al., 2003). The same conditions of higher activity in Perna viridis also noted in long term exposure in this study. Though SOD activity in response to Season and PAH was evident from this study but (Power and Sheehan, 1995) reported that SOD as an biomarker index for pesticide pollutants.

Glutathione reductase (GSH): Among the three antioxidants studied GSH seems to be highly sensitive to environmental dynamic such as dissolved oxygen, salinity and temperatures, besides xenobiotics. The seasonal change in environmental parameters modulates the induction of antioxidant enzymes as a protective measure against stress including potential toxicity which increased the ROS formation (Santovito et. al., 2005). This GSH enzyme catalyzes the reduced nicotinamide adenine dinucleotide phosphate (NADPH)–dependent reduction of the disulfide bond of oxidized glutathione. A major function of GSH is to serve as a reductant in the oxidation-reduction processes; a function resulting in the formation of glutathione disulfide (GSSG). Glutathione S-transferases (GSTs) are ubiquitous multifunctional enzymes, which play a key role in cellular detoxification. The enzymes protect the cells against toxicants by conjugating them to glutathione, thereby neutralizing their electrophilic sites, and rendering the products more water-soluble for elimination. The temperature stress activates increased level of total glutathione, initially which serves as a compensatory mechanism, to allow mussels to maintain constant GSH / GSSG ratio despite heat induced oxidative stress (Lushchak et. al., 2006). In this study the seasonal and experimentally given temperatures exert stress to the GSH activity. Similar effect in the long term exposure to temperature was recorded by Zhang et. al., (2003). Notably the GSH level increased positively in response to temperature in the laboratory exposure, surprisingly it decreased at longer time exposure in the field ie., during summer.

The GSH and catalase imparted an identical trend during summer season (r = 0.998, P < 0.01). The same condition was observed in the organs like liver, gill and foot of M.galloprovincialis and H. fossilis (Khessiba et. al., 2005; Parihar et. al., 1997), when exposed to heat. The liver showed higher enzyme activity during both the post and pre monsoon seasons. Identical season related higher enzyme elevation of GSH (both post and premonsoon) than other seasons were recorded (Meister, 1983).

Among all the station and all the seasons studied, the Rayapuram fishing harbour (Station-1) evidenced higher GSH activity when compare to other stations and very lesser activity in Parangipettai (Station-3). It would reveal the higher level of oil pollution in this station-1 implicate stress to the inhabiting mussels, thus the mussels produced more of GSH for defense.

The observed lowest GSH activity during summer and monsoon in all the stations indicates the climatic changes besides the xenobiotics (ie., highest/ lowest salinity and temperature stresses that deviate from the required optimum conditions for best performance) impart stress and thus modulates the activity. The same condition was already experienced in Uria aalge (Khan, and Ryan, 1991). It would further reveal the extreme climatic conditions may reduce the defense enzyme activity, thereby the loss of defense may leads death of the animals (Zakharov et. al., 2002; Frei, 1999; Geracitano et. al., 2002). Kappus (1985) stated the GSH and other antioxidant enzyme activity depends on the survival ability relevance to the organism’s biology. The instant depletion of GSH level would probably reveals enhanced risk of oxidative stress in digestive gland, gills and other parts of the body that induces the membrane and cellular damages.

Identical higher productions were obtained in rain bow trout fish exposed Phenobarbital, p,p-di chloro-diphenyl -dichloro-ethylene (DDE), or the prototypal oxidation-reduction cycling compound 2,3-dimethoxynaphthoquinone (Petrivalsky et. al., 1997). In the present study the long term exposure to elevate the xenobiotic concentrations inhibited the GSH reaction in P.vidis during summer season in the field (Figs.), the same condition was already experienced in Uria algae (Khan, and Ryan, 1991). In another evaluation on the CYP 450 isoforms which are considered as biomarker enzymes showed higher activity during summer seasons and thus the present GSH depletion does not reflects oxidative stress during summer.

Figure.1 Catalase activity of Perna viridis liver s9 fraction during different seasons

Figure.2 Glutathione reductase activity in P.viridis liver s9 fraction during different seasons

References

Rajagopal, S., G, van der Velde., J, Jansen., M, van der Gaag., G, Atsma., J. P. M, Janssen-Mommen., H, Polman and H.A, Jenner (2005). Thermal tolerance of the invasive oyster Crassostrea gigas: Feasibility of heat treatment as an antifouling option Water Research 39:4335-4342.

Bhat, S and P.V, Desai (1998). Effects of thermal and salinity stress on Perna viridis heart (L.), Ind.Jour.Exp.Biol., 36: 916-919.

Parihar, M. S., T, Javeri., T, Hemnani., A. K, Dubey., P, Prakash (1997). Response of superoxide dismutase, glutathione peroxidase and reduce glutathione antioxidant defense in gills of freshwater catfish (Heteropneustes fossilis) to short term elevated temperature, Jour.Therm.Biol., 22: 151-156.

Khessiba, A, M. Romeo and P, Aissa (2005). Effect of some environmental parameters on catalase activity measured in mussels (Mytilus galloprovincialis) exposed to lindane, Environ. Poll.133 275-281.

Brito Correia J., M, Pereira Caldas., N, Shohoji and A, Cabral Ferro 1996. Dependence of internal oxidation rate of water atomized Cu-Al alloy powders on oxygen partial pressure, Journal of Materials Science Letters, 15, 6.

Sturve, J., A, Berglund., L, Balk., K, Broe., B, Bohmert., S, Massey., D, Savva., J, Parkkonen., E, Stephensen., A, Koehler and L, Forlin (2005). Effects of dredging in Goteborg harbor, Sweden, assessed by biomarkers in eelpout (Zoarces viviparous), Environ. Toxicol. Chem., 24: 1951-1961.

Cossu M., M. T, Perra., M, Piludu and M. S, Lantini (2000). Subcellular localization of epidermal growth factor in human submandibular gland. Histochem. J, 32: 291–294.

Santovito, G., E, Piccinni., A, Cassini., P, Irato and V, Albergoni (2005). Antioxidant responses of the Mediterranean mussel, Mytilus galloprovincialis, to environmental variability of dissolved oxygen, Comparative Biochemistry and Physiology C140, 321-329.

Lushchak, V. I and T. V, Bagnyukova (2006). Temperature increase results in oxidative stress in goldfish tissues. 2. Antioxidant and associated enzymes, Comp. Biochem. Physiol. 143:36 – 41.

Zhang, J.F., H, Sen., T. L, Xu., X.R, Wang., W. M, Li and Y.F, Gu (2003). Effects of Long-Term Exposure of Low-Level Diesel Oil on the Antioxidant Defence System of Fish, Bull.Environ.Contam.Toxicol., 71:234-239.

Power, A and D, Sheehan (1995). Seasonal variations in the levels of antioxidant enzymes in Mytilus edulis, Biochemical Society Transactions., 23, 354S-362S.

Lushchak, V. I and T.V, Bagnyukova (2006). Temperature increase results in oxidative stress in goldfish tissues. 2. Antioxidant and associated enzymes, Comp. Biochem. Physiol., 143:36 – 41.

Meister, A and M.E, Anderson (1983). Glutathione, Ann. Rev. Biochem., 52:711–760.

Khan, R. A and K, Nag (1993). Estimation of hemosiderosis in seabirds and fish exposed to petroleum. Bulletin of Environmental Contamination and Toxicology. 50:125-131.

Zakharov, S.D., Rokitskaya, T. I., Shapovalov, V. L., Y. N, Antonenko and W. A, Cramer. Tuning (2002). The membrane surface potential for efficient toxin import, Proc. Natl. Acad. Sci. USA, 99: 8654-59.

Geracitano, L.A., J. M, Monserrat, and A, Bianchini (2002). Physiological
and antioxidant enzyme responses to acute and chronic exposure of Laeonereis acuta (Polychaeta, Nereididae) to copper, J. Exp. Mar. Biol. Ecol. 277:145-156.

ANAND ET AL., IN-VESSEL COMPOSTING OF FOOD WASTES

Anand M, I.S. Bright Singh, Anushree N S, John. J. Vathikulam, In-Vessel Composting of Food Wastes, (Ed.) S.Jisha, B.Hari & T.K.Remesan, Proc. Nat. Sem. on Env. Biotech. Chall. and Oppor.,  Envirotech-2008, P.G. Dept. of Zoology, S.N.C. Natiika, pp1-28-38.

(School of Environmental Studies, CUSAT, Kochi, e.mail: anandm@cusat.ac.in)

Abstract

Developing countries like India generate more food waste compared to developed countries.  The putrefying nature of food waste makes it less viable for storage and transportation.  It also hinders the recovery of recyclable materials.  Limited land resource available for dumping of waste which is ever increasing with increase in population, has lead India to think over techniques of reducing waste at the source itself.  Composting is one such and the most viable technique to serve the purpose.  The use of small scale in-vessel composting systems at household level is a  better way to dispose off the kitchen waste and turn it into compost on-site in a relatively short time.

It is envisaged that a fully developed and highly efficient in-vessel composting system will provide one of the practical solutions to deal with the tremendous amount of food waste generated and related problems faced by housing-societies, community halls, shopping centers, hotels & restaurants, institutions like universities, colleges and schools etc.

The concept of in-vessel composting has a great scope in India because it is simple to use at the backyard; saves lot of space; easy to operate on all weather conditions and easy handling of the waste.  The whole process is clean and economical, when compared to conventional methods of composting like windrows, static pile etc.  Presently, simple to highly sophisticated in-vessel composting systems are widely used in western countries.

Introduction

Waste management techniques: Composting the biodegradable part of the solid waste by adopting the latest technology, at a rate fast enough to mach the rate of generation of the waste, is an environment friendly and cost effective method.  Even though a variety of technologies for utilization of waste namely Incineration, Pyrolysis, Anaerobic digestion to produce gas, Thermal gasification, Plasma arc, Sanitary land fill, Pelletization, Micro wave and Laser Waste Destruction are available, “Aerobic composting” of the urban solid waste is opted by many Scientists and Technocrats in India, owing to its simplicity in the process, suitability for the Indian conditions, low cost factor and less pollution effects.  Most of the Technologies, except the aerobic composting process, are either costly or pollute the environment by emitting toxic fumes, including dioxins.  The concept of “Reduce, Reuse and Recycle” could be fully contemplated by adopting composting technology.  It is imperative therefore, that relevant technologies are evolved to treat and recycle waste in order to keep the ecosystem clean.  Over the recent past, composting process has been scientifically studied and engineered, thereby allowing it to become a more efficient and manageable waste disposal method.

Composting – the ideal method: Composting is the process of producing compostthrough aerobic decomposition of biodegradable organic matter.  The decomposition is performed primarily by aerobes, although larger creatures such as ants, nematodes, andoligochaete worms also contribute.  This decomposition occurs naturally in all but the most hostile environments, such as within landfills or in extremely arid deserts, which prevent the microbes and other decomposers from thriving.  Composting can be divided into the two areas of home composting and industrial composting.  Both scales of composting use the same biological processes; however techniques and different factors must be taken into account.

Composting is the controlled decomposition of organic matter. Rather than allowing nature to take its slow course, a composter provides an optimal environment in which decomposers can thrive.   To encourage the most active microbes, a compost pile needs the correct mix of the following ingredients Carbon, Nitrogen, Oxygen (from the air) andwater.  Decomposition happens even in the absence of some of these ingredients, but not as quickly or as pleasantly.  (For example, vegetables in a plastic bag will decompose, but the absence of air encourages the growth of anaerobic microbes, which produce disagreeable odors. Degradation under anaerobic conditions is called anaerobic digestion).  Two types of composting system have been widely applied: window systems and in-vessel systems.

The windrow composting process: Windrow composting refers to the process of mechanically stacking waste into long composting piles, often 1-3 metres in height with triangular cross-sections.  Windrows may be either mechanically turned to mix the material and to promote aeration or else actively aerated using pumps as with static pile systems.  Further details of the many variations in windrow composting may be found in Haug (1993).  A feature of all composting systems is that sufficient mass of material must be present to allow reaction heat to be trapped, thereby increasing composting temperature.  The composting process is often considered to comprise three distinct phases, which may be defined by the different temperatures ranges at which each phase takes place:

An initial phase taking place at temperatures close to ambient (mesophilic, upto 40oC).

A phase at elevated temperatures, where biological activity causes heating to thermophilic temperatures (40oC to 80oC).

A maturation phase, following thermophilic activity where more complex substrates are degraded at a slower rate (hence a slower rate of heat generation).

A range of organisms are involved in the complete decomposition of organic matter under controlled conditions such as bacteria, actinomycetes, fungi, protozoa, annelids, arthropods.  The controlled composting process is mediated by a diverse community of micro–organisms, many of which are not individually capable of fully mineralising the biodegradable materials. Decomposition during composting may proceed via a series of intermediate compounds degraded by different sets of organisms.  These intermediate compounds may be phytotoxic and/or odorous.  These intermediate organic products may either serve as substrates for other micro– organisms or may remain, for a period of time, in the compost residue.

In-vessel composting systems: A number of studies have investigated the process engineering and technical aspects of commercial composting with particular regard to more advanced methods such as static pile and in–vessel systems.  Examples are De Brtoldi (1992), Hoitink et al.,(1993), Canet & Pomares (1995), Lopez–Real & Baptista (1996), Lynch & Cherry (1996). More advanced systems of in-vessel composting are seen as having many advantages over open air windrow systems.  As for all waste processing systems, Slater, Frederickson and Gilbert (2001) contend that open windrow composting has the potential to pollute the environment, cause disamenity to the locality or harm topublic health if good operating practices are not observed.  In order to minimise theenvironmental impact of composting and to enhance and control the composting process, highly sophisticated enclosed composting systems have been developed throughout Europe, based on forced aeration technology.  These often use computer–controlled systems to manage the aeration rate, moisture content and temperature of the composting materials. They have been termed ‘in–vessel’ and cover a wide range of composting systems.  The principle behind an in–vessel system is to provide air and moisture at a level that optimises microbial activity as rapidly as possible and then maintains it for the desired period.  This is obviously easier than in open composting operations where control over ambient temperatures and the elements is more challenging.  It is also possible for more difficult feedstocks to be composted using in-vessel systems since they are protected from the wider environment and enclosure helps prevent pathogen vectors such as scavenging birds and vermin from gaining access to the feedstock.  In addition, the enclosure of decomposing organic materials allows potentially harmful emissions to be contained and possibly treated prior to release into the environment.

In-vessel systems share the common feature that the material being composted is contained and, usually, enclosed.  In most cases, enclosure means that the composting materials are not affected by the external environment (temperature, rainfall, etc.) and the processing conditions can be controlled accurately to make composting more efficient.  In addition, emissions from enclosed composting processes, such as bioaerosols, odours and leachate, can be monitored and treated.

In-vessel composting systems have been developed from a wide range of industries.  Tunnels have come from the mushroom industry, air handling equipment and computer controls from the development of greenhouses and mixing techniques from sewage processing.  This has led to the diversity of in-vessel systems that are now employed for the ‘active’ thermophilic phase of composting.  With the development of the in-vessel composting sector there is potential to transform increasing amounts of biodegradable waste into higher value compost products.  The composting industry is likely to introduce in-vessel technology in combination with other traditional composting methods.

Food waste composting: Food waste has unique properties as a raw compost agent, because it has a high moisture content and low physical structure. However it is important to mix food waste with a bulking agent like sawdust, yard waste etc., which will absorb some of the excess moisture as well as add structure to the mix.  Bulking agents with a high C: N ratio’s such as sawdust and yard waste are good choices (Chynoweth, et.al., 2003). Donahve et.al., (1998) demonstrated that food waste was successfully composted with sawdust and mulch chips in an in-vessel system within 14 days, after which the product was placed in windows for the curing stage.  Now composting is gaining increased attention for treating food wastes with various agricultural by-products in different systems (Droffner&Brinton, 1995; Elwell, et.al., 1996; Donahve et.al., 1998; Laos et.al., 1998; Favcette et.al., 2001; Seymour et.al.,; Tomati et.al., 2001; Filippi et al., 2002 and Daset.al, 2003).

Recently Iyengar, et.al., (2005) has successfully demonstrated that an indigenously developed in-vessel composting system proved to be efficient, eco-friendly, cost-effective and nuisance-free solution for the management of household wastes.  Chang et.al., (2006), also proved successful in thermophilic composting of food waste.  Droffner and Brinton (1995) reported that Salmonella and E.coli were inactivated in 9 days at 60 oC – 70 oC in bench scale composting of food waste with leaves, and very recently Joung dae kim et.al.,(2007) evaluated a pilot-scale in-vessel composting for food waste treatment and found out that the final compost produced along with the bulking agent was satisfactory for agricultural application in terms of electrical conductivity as a salt content index and heavy metal contents.  Today in-vessel composting systems are an established technology in western countries for the treatment food wastes; yard wastes; fish wastes; slaughter house wastes etc, the system ranges from simple to highly sophisticated computer controlled mobile units.  However, the same technology cannot be applied to the Indian conditions because the selection of the system is dependent on the nature of the waste to be composed, available manpower and economic conditions.

Potential factors for in-vessel composting of food waste in India: The characteristics of the municipal waste in India indicates a high biodegradable fraction of more than 50%.  More over Viswanathan et.al., (2004), described that the MSW stream in most Asian countries is dominated by organic portion composed of food wastes, yard wastes, and mixed paper.  The biodegradable portion of the waste mainly remained in the waste stream. The average moisture content is relatively high, that is greater than or equal to 50%, (Zurbrugg, 2002).  In this regard, waste is not suitable for incineration because it requires high-energy input to bring the waste to its ignition level. Nevertheless, land filling of such waste creates nuisance owing to the generation of highly concentrated leachate, methane gas emission, and quick settlement of waste due to decomposition that eventually affects the stability of landfill.  The best disposal solution for this type of waste is ‘aerobic composting’ and today composting has emerged as an attractive option for treating food wastes due to less environmental pollution and beneficial use of the final product (Filippi et al., 2002; Daset.al., 2003; Mbenito et.al., 2006 and. Zenjari et.al., 2006).

Aims and Objectives

Project aim

To develop a pilot scale in-vessel composting system for the treatment of food wastes.

To investigate the performance of the in-vessel composting system with respect to:

– enhancing rates of waste stabilisation and compost maturation

– enhancing the added-value characteristics of the finished compost

Project objectives

• To undertake a pilot scale in-vessel composting trial as well as windrow composting, which is the experimental control.

• To undertake an extensive programme of physico-chemical analyses on all waste and composted materials during the trials to assess the effect of the composting processes.

• To identify key processing parameters such that commercial-scale in-vessel composting, may be reliably and consistently practiced in order to achieve consistent compost products

• To determine the comparative capital and operational costs as well as potential revenues from the final product.

The project outline is described below including key sampling and analysis points:

Monitoring and Analyses                           Composting and testing

Procedures

Initial household waste

Physico-chemical analysis of initial                                             household waste

↓

in-vessel treatment

Periodic monitoring of waste during                                        Composting period

↓

stabilized/ matured organic matter

Analysis of material after                                                       in-vessel composting

↓

Programme of value additionand final maturation

Screening of composts to <10 mm                                            for bioassay tests

Conclusion

For composting to be accepted as a viable alternative to land filling and to other methods of municipal solid waste treatment such as incineration, effective separation of the organic fraction needs to be achieved at the source of generation, i.e., the individual houses. Moreover, early separation of the waste flows and their decentralized recycling could contribute to reducing the waste quantities to be transported by the city and to free capacities which can be used elsewhere (Zurbrugg et.al., 2004).

Today the world is moving towards Zero Waste Management model, which concentrates on the challenge to recover the recyclable fraction of household refuse, at least 95% of the total amount generated ( 80% organic wastes, 15% inorganic ), so that only 5% would need to be handled by the Municipal Corporation. The best way to handle 80% of the organics generated at the household level is to compost it on-site. Several methods of composting are in vogue in India and any one or many methods of composting can be applied in given situations. Selecting an appropriate method of composting appropriate to the place based on resource availability as well as limitations should be applied to evolve a most suitable model for a given place. As a response, in many cities, non-governmental organizations have started developing neighborhood waste collection services, as well as initiating composting and recycling activities. These moves are backed up by new municipal solid waste management and handling rules published in 2000, which among other recommendations, require source segregation and waste recovery. But till today no single technology has gained wider acceptance among the public, due to one reason or other.

Solid Waste Management is not an isolated phenomenon that can be easily compartmentalized and solved with innovative technology or engineering. It is particularly an urban issue that is closely related, directly or indirectly, to a number of issues such as urban lifestyles, resource consumption patterns, jobs and income levels, and other socio-economic and cultural issues. All these issues have to be brought together on a common platform in order to ensure a long-term solution to urban waste.

There is a whole culture of waste management that needs to be put in place – from the micro-level of household and neighborhood to the macro levels of city, state and nation. The general assumption is that SWM should be done at the city-level, and as a result, solutions tried out have been essentially end-of-pipe (‘End-of-pipe’ refers to finding solutions to a problem at the final stage of its cycle of causes and effects. In the case of urban waste, it means focusing on waste disposal rather than waste recycling or waste minimization).

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