Pesticides future

Since the early 1940s, insecticides have been of immeasurable value in curbing the ravages of insect pests. In the words of the National Academy of Sciences "...when their use is approached from sound ecological principles, chemical pesticides provide dependable and valuable tools for the biologist. Their use is indispensable in modem society. There are many problems of insect pest control for which the use of chemicals provides the only acceptable solution. Chemical pesticides will continue to be one of the most dependable weapons for the entomologist for the foreseeable future" (6). 

Sustainable Agriculture. The third factor that will influence the future of pesticide sales is the emphasis on sustainable agriculture systems that rely on more natural pest control methods and reduced pesticide usage. These are integrated systems that requke nutrients and crop protection chemicals from on-farm natural sources and cultural methods. Many current sustainable farms are site-specific systems that may depend on the soils in a... 

Another section of the EPA, the Office of Prevention, Pesticides, and Toxic Substances (OPPT), has recently updated and harmonized its testing guidelines for evaluating the developmental and reproductive effects of pesticides and industrial chemicals to include an assessment of endocrine disrupting properties. These guidelines will be used in future testing of pesticides under both the Toxic Substances Control Act (TSCA) and the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). 

The full extent of the toxicity of pesticides to aquatic life is not known. Although chronic toxicity testing is required for new substances, little is known about the long-term effects of older pesticides. Also, very little is known about the toxicity and occurrence of the products formed when pesticides break down (metabolites) or the many non-pesticidal additives (co-formulants and adjuvants) used in pesticide formulations. However, the future is looking brighter. New modelling techniques, EQS development, and the involvement of the NRA in the pesticide registration process, coupled with the development of newer, less persistent pesticides with lower dose rates, all should help to reduce the risk of pesticide pollution. 

Future studies must focus on those specific agricultural technologies that have contributed to the increased use of pesticides during the past 40 years, and why crop losses to pests continue to Increase. Research needs not only to identify the detrimental technologies, but, more Important, develop ecologically sound practices that farmers can use as profitable substitutes (15). 

Gilliom RJ, Alexander RB, Smith RA. 1985. Pesticides in the nations rivers, 1975-1980, and implications for future monitoring. U.S. Geological Survey Water Supply Paper 2271. 

National Research Council, The Future Role of Pesticides in U.S. Agriculture, National Academy Press, Washington, DC (2000). 

Moreover, new technologies such as LC/MS/MS should be considered and their potential should be recognized in the future. Currently food control laboratories monitor only a part of the pesticides used in their routine work. They prefer active ingredients that can be analyzed by multi-methods or some group-specific methods, because resources to check all relevant pesticides are normally not available. Therefore, many a.i. are monitored only on a case-by-case basis or not at all. An LC/MS multi-residue method, which may be developed in the future, could cover this gap to a large extent. 

The development of new fiber coatings in the near future should further improve the specificity of SPME and overcome some of the observed matrix effects. Quantification by stable isotope dilution gas chromatography/mass spectrometry (GC/MS) may assist in improving analytical performance. Along with the possible application of micro LC and capillary LC columns to in-tube SPME, the development of novel derivatization methods and the potential for the analysis of fumigant pesticides, SPME appears to be a technique with a future in the analysis of pesticide residues in food. 

As the years progress, so the pace of new technological development seems to follow an exponential curve. It is impossible to predict all the changes that will occur, even in the near future, so we have selected four which we feel will have a significant impact on the work of pesticide residue analysts over the next 1-2 decades. 

The need to develop and use chiral chromatographic techniques to resolve racemates in pesticide residues will be driven by new hazard and risk assessments undertaken using data from differential metabolism studies. The molecular structures of many pesticides incorporate chiral centers and, in some cases, the activity differs between enantiomers. Consequently, in recent years manufacturers have introduced resolved enantiomers to provide pesticides of higher activity per unit mass applied. For example, the fungicide metalaxyl is a racemic mix of R- and 5-enantiomers, both having the same mode of action but differing considerably in effectiveness. The -enantiomer is the most effective and is marketed as a separate product metalaxyl-M. In future, it will not be satisfactory to rely on hazard/risk assessments based on data from metabolism studies of racemic mixes. The metabolism studies will need to be undertaken on one, or more, of the resolved enantiomers. 

The use of field forms documents all the observations of the activities of the workers for future reference. The observations may be used to revisit exposure events and help define protective equipment measures for the pesticide label. 

Many other topics in addition to those covered by the titles in these symposia were proposed, and may form the basis for future symposia. Other suggestions included the broad and important topic of formulation, which may many times have an important relation to the effectiveness of the economic poison for the purpose for which it is designed, may be modified to prepare a given pesticide for different uses, and may also influence its toxicity to warm-blooded animals. A report of work on methods of application and their relation to effectiveness was suggested, including much work on the use of concentrated sprays. 

Pesticides and the equipment with which they are applied are so fundamentally associated that it is astonishing to see how often these two items are separated. Pesticides are frequently sold in a foreign area with complete disregard of the available means of application yet the whole future market depends mainly upon the proper distribution of the materials. The want of suitable equipment can be a very serious factor in retarding the use of economic poisons. 

Preliminary work on several of these projects has already been in progress for over a year. These initial efforts will be expanded and intensified when the committee on pesticides becomes activated in the near future. However, pursuance of this program will require the support and cooperation of all segments of science and industry. Advisory bodies from the various interested groups will be called upon for recommendations and suggestions on problems which fall within their field. In turn, the assistance of this committee will be available, not only to the medical profession, but to all other groups in any direction in which the committee may be useful. 

The scientific community is indebted to Alexey Yablokov and Lev Fedorov for carefully examining the pesticide impact on public health and the environment. Their studies add to our knowledge and their results suggest ways that public health and environmental pesticide related problems could be avoided. Given the food security needs of the rapidly expanding world human population, a safe and a productive agriculture are vital for the future. 

This work is not an attempt to look at the past and future of the pesticide problem from the environmental point of view. After the general discussion of pesticides properties and use in the USSR (Chapter 1), we look successively at the unexpected consequences of pesticide use, for the natural environment, humans, and for agriculture itself.This work concludes with Lessons Learned from Pesticides, food for thought for policymakers, ecologists, and farmers. 

In the future, we must expect ever-newer types of pesticide transformations in the environment, which will be accompanied by unpredicted consequences. It is practically impossible to guess what these consequences may be. 

Contamination of the environment with DDT and other OCPs will remain a global phenomenon for many years to come. No one is protected from pesticide exposure, especially from exposure to OCPs. Thus, in the near future, all biochemical processes in living organisms will take place under unprecedented complex and practically unpredictable conditions. 

Pesticides are one of the main factors threatening biodiversity on the planet. In the near future, pesticide effects on animals will not lessen, but grow background concentrations of some pesticides have almost reached levels that seriously affect life processes. 

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