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[EBOOK] Pesticide Residues in Coastal Tropical Ecosystems (Distribution, fate and effects), More writer, Published by Routledge

The second half of the twentieth century saw tremendous increases in world food production brought about by revolutionary changes in agriculture. With the introduction and widespread acceptance of DDT as a nearly universal insecticide for agriculture in 1944, crop losses to insects declined rapidly and food production accelerated through a paradigm shift from small family farms to industrialized agriculture. By the late 1960s when insect resistance to DDT and the rising concern for environmental contamination caused by DDT and other organochlorine pesticides became apparent, other pesticide chemistries such as the organo-phosphates, carbamates, organotins, and second generation pyrethroids had become available. These compounds filled the pest control gap as organochlorine use gradually declined from the combination of resistance and environmental regulatory pressures. The Green Revolution of the 1980s introduced high-yield hybrid seed varieties, which in combination with chemical fertilizers, resulted in dramatic increases in crop yields; world rice and wheat yields tripled between 1950 and the mid-1980s. With the recent development of genetically modified transgenic crops, there has been a further shift to large-scale plantation farming. The shift to monoculture-based industrial farming has brought about the introduction of many new and novel pesticide chemistries, primarily because monocultures are more susceptible to pest population explosions than the old-style mixed crop planting that would sustain and promote insect predator populations.

Because of the environmental problems associated with the organochlorines, pesticide regulatory agencies were established, initially in developed countries located in temperate climes, and began issuing regulations to control pesticide production and use. These regulations required data about the efficacy and nontarget effects of individual pesticides. Consequently, most of the data generated for regulatory purposes was based on data obtained from field research in temperate climates. Thus, guidelines for using pesticides in the tropics have been based on research conducted in Europe and the United States. While some tropical countries recognized the potential problems associated with this fact, they had little recourse but to adopt regulations copied from their more affluent northern neighbors. Over the past 20 years, many developing countries have adopted some form of environmental protection, either through establishment of a regulatory agency or agencies or through adoption of a body of law to regulate the pesticide industry. As a result, some tropical countries are taking a more proactive approach to regulating pesticides by requiring licensing data for individual pesticides to be generated in soils, climates, and under conditions reflective of local conditions. This is an encouraging sign of environmental responsibility There are groups in some countries, pushing for national long-term pesticide residue monitoring programs for foodstuffs, surface waters, or biota. However, these efforts are likely to be stillborn until and unless the international community, viz. the developed countries, assists by providing stable long-term funding to support these efforts.

This book grew out of a research program to determine the distribution, fate, and effects of pesticides in the tropical marine environment as envisioned and led by Fernando Carvalho at the Marine Environmental Laboratory of the International Atomic Energy Agency in Monaco. He recruited respected scientists from 17 countries and charged them to accomplish a specific set of objectives. These included measuring current levels of pesticide residues in coastal environments, characterizing the cycling and fate of pesticides, evaluating the effects of their residues on marine biota, assessing the risk associated with pesticides in coastal tropical ecosystems, and advising on measures to protect the tropical marine environment. With funding provided by the Swedish International Development Authority, a coordinated research program (CRP) was established and through joint activities including courses on aquatic toxicology, ecological risk assessment, and quality assurance and quality control; training workshops; and participation in international scientific meetings, the participating scientists were forged into a dynamic working group. As their research yielded new information about the extent of pesticide residues in coastal environments, they became familiar with the results of other groups working in their respective countries. The genesis of this book came from discussions between themselves and other colleagues. As the idea evolved, it became apparent that more than a summary of research results would be needed to convey the potential for pesticides to affect the tropical marine environment. Contributing colleagues were asked to include some basic information about their country, e.g., location, extent, geographic features, etc.; brief histories of pesticide use with import and export data where available; summaries of their pesticide regulations and descriptions of the regulatory bodies in their country; descriptions of pesticide research in their country including residue levels in surface waters, coastal waters, sediments and biota; and synopses of efforts in their respective countries to limit the growth of pesticide use, either through Integrated Pest Management efforts, public education programs, or through other means. Readers will discover that individual chapters are not rigidly structured as some authors tended to emphasize one area more than another. As editors, we felt that this less-rigid format made for a more interesting book and provided some information about a country’s focus or concerns either through inclusion or omission. Our hope is that the resulting book will bring together as much of the current peer-reviewed, government, and “grey” literature on pesticide use, fate, and effects in the tropics as possible and serve as a state-of-the-science summary for generating the next set of research projects by scientists and serve as a basis for management decisions regarding coastal tropical ecosystems.

Obviously, this project would never have come to fruition without the continued efforts of its contributors to respond to editorial suggestions and supply updated information for their respective chapters. The editors would also like to thank the students of Professor Klaine’s laboratory in the Department of Environmental Toxicology, Clemson University, for their assistance in reviewing page proofs of the book.

[EBOOK] Pesticide Residues in Coastal Tropical Ecosystems (Distribution, fate and effects), More writer, Published by Routledge

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