Biodegradation Of Pesticides

When first developed, chlorinated pesticides such as DDT, dieldrin, and mirex were received with open arms, quickly becoming popular as effective, economic agents against pests. But evidence began to mount that residues of these chemicals remained in the environment, not breaking down, often appearing in plants and animals. By the late seventies many pesticides had achieved a terrible notoriety and were subsequently banned in a number of countries. Of tremendous concern, then, is the persistence of pesticides in the environment. The major thrust of research and development in the area of pesticides has properly been the creation of substances that are both effective and degradable. Yet in order to successfully promote the use of biodegradable pesticides, one must fully understand the mechanism of degradation, and it is to this vital subject that we address ourselves in the present volume. According to the Biodegradation Task Force, Safety of Chemicals Com mittee, Brussels (1978), biodegradation may be defined as the molecular degradation of an organic substance resulting from the complex action of living organisms. A substance is said to be biodegraded to an environmentally acceptable extent when environmentally undesirable properties are lost. Loss of some characteristic function or property of substance by biodegradation may be referred to as biological transformation.

This book contains a collection of different biodegradation research activities where biological processes take place. The book has two main sections: A) Polymers and Surfactants Biodegradation and B) Biodegradation: Microbial Behaviour.

This new volume offers comprehensive information on microbial adaptation for pesticide degradation. Among the many topics covered in its 20 chapters are a general description of enhanced biodegradation as it occurs in an agricultural context; the microbial aspects of enhanced biodegradation, including the genetics, biochemistry, and ecology of pesticide-degrading microorganisms; and the potential impact of enhanced degradation on pesticide fate in aquatic systems and groundwater. Practical options for the management of enhanced biodegradation are also examined, both to enable continued agricultural use of susceptible pesticides and also to exploit the degrading capacity of microorganisms for waste disposal and environmental remediation.

This book focuses on the microbial degradation of endosulfan, lindane, chlorophenols, organochlorine, aldrin, dieldrin, isoproturon and atrazine, etc. which are commonly used in crop fields to kill the pests. Further, it illustrates the role of degradative enzymes, metabolic pathways of degradation, toxicity of metabolites, and the factors regulating the pesticide degradation. In view of persistence of synthetic pesticides, scientists have discovered suitable microbes, such as bacteria, fungi and algae (naturally occurring or genetically engineered) over the years. After successful trials under laboratory and field conditions, these microbes are being used to degrade chemical pesticides in agriculture. As of now 2.56 billion kg of chemical pesticides is used every year to protect agricultural fields against pest attack. These technologies have been found to be highly effective, eco-friendly and cost-effective without disturbing the agro-ecosystems. As this book contains review articles contributed by various researchers from different countries whose work demonstrates recent advances in microbial degradation of pesticides, it will serve as a ready reckoner and also a valuable quick reference guide for scientists, academicians, cultivators and industrialists alike.

In this volume, experts from universities, government labs and industry share their findings on the microbiological, biochemical and molecular aspects of biodegradation and bioremediation. The text covers numerous topics, including: bioavailability, biodegradation of various pollutants, microbial community dynamics, properties and engineering of important biocatalysts, and methods for monitoring bioremediation processes. Microbial processes are environmentally compatible and can be integrated with non-biological processes to detoxify, degrade and immobilize environmental contaminants.

The quality of agricultural soils are always under threat from chemical contaminants, which ultimately affect the productivity and safety of crops. Besides agrochemicals, a new generation of substances invades the soil through irrigation with reclaimed wastewater and pollutants of organic origin such as sewage sludge or cattle manure. Emerging pollutants such as pharmaceuticals, nanomaterials and microplastics are now present in agricultural soils, but the understanding of their impact on soil quality is still limited. With focus on in situ bioremediation, this book provides an exhaustive analysis of the current biological methodologies for recovering polluted agricultural soils as well as monitoring the effectiveness of bioremediation.