Generic pesticides

Generic pesticides (those that have exceeded their patent life) represent over half of the global crop protection market (US 18 000 million of end-user sales in 1998). The patent expiry of important molecules such as the pyrethroids, triazole fungicides and glyphosate has resulted in substantially reduced prices, and there have been tensions between the major multinational and generic (often national) pesticide companies. Nevertheless, some 70% of the profits from multinational companies come from compounds that have exceeded their normal, 20-year patent life (i.e. approximately 13 years of profitable life Finney, 1988). In response, the major multinational companies have attempted to maintain their market share... 

This book provides an up-to-the-minute picture of the current status of research on measurement and risk assessment of dermal pesticide exposure for agricultural workers. The chapters also provide an insight into some newer areas (applications of mathematical models, use of fluorescent tracer materials, and extrapolation from a computer data base of generic pesticide exposure data) that will undoubtedly be receiving increased attention in the future. 

Field studies are required to provide a more reaUstic picture of the dissipation of the parent compound and those degradates determined to be significant. Under field conditions pesticides are exposed simultaneously to the individual dissipation processes that were examined separately in the laboratory studies. Thus, in field studies, some dissipation processes may be altered due to competition and interaction. Requirements for spray drift data were outlined in draft Subdivision R, but the EPA agreed that data generated on a generic basis by an industry consortium could represent the potential for drifting of individual pesticides. 

R.C. Honeycutt, The Usefulness of Farm Worker Exposure Estimates Based on Generic Data, in Dermal Exposure Related to Pesticide Use Discussion of Risk Assessment, ed. R.C. Honeycutt, G. Zweig, and N.N. Ragsdale, ACS Symposium Series 273, American Chemical Society, Washington, DC, pp. 369-375 (1985). 

Assist in Standardization of Nomenclature. The profusion of trade names, initials, numbers, and combinations thereof for pesticides contributes to misuse and errors in the handling of these preparations. The coining of common or generic names for pesticides is a recent and commendable innovation in this field of science. It presents many problems which require the services of many groups. The many years of experience of the Council on Pharmacy and Chemistry in the development of generic names for drugs is at the disposal of the committee in its consideration of nomenclature problems. 

Harvesting carnations will account for average transfer factors of about 2000 cm2/hr for pesticides applied by high-volume applications. A critical evaluation of existing data may generate more reliable generic transfer factors for use in the re-entry model. 

OECD. 2003. Descriptions of Selected Key Generic Terms Used in Chemical Hazard/Risk Assessment. Joint Project with IPCS on the Harmonisation of Hazard/Risk Assessment Terminology. OECD Series on Testing and Assessment No. 44. Environment Directorate, Joint Meeting of the Chemicals Committee and the Working Party on Chemicals, Pesticides and Biotechnology. ENV/JM/MONO (2003)15. Paris OECD. 

When the data for a situation of specihc interest are inadequate, a common approach is to make some use of more generic information, including possibly information less representative of the situation of specific interest. For example, if the information for a specihc pesticide is inadequate, then some features of an analysis may be based on information from a set of other pesticides, considered to be comparable. This can be appropriate particularly for an early-tier assessment, in which case the criteria may be designed to be protective, so far as we can judge. 

The use of uncertainty analysis and probabilistic methods requires systematic and detailed formulation of the assessment problem. To facilitate this, a) risk assessors and risk managers should be given training in problem formulation, b) tools to assist appropriate problem formulation should be developed, and c) efforts should be made to develop generic problem formulations (including assessment scenarios, conceptual models, and standard datasets), which can be used as a starting point for assessments of particular pesticides. 

There seems to be a desire among the workshop participants to develop a series of standard distributions, or distribution parameters, for exposure and effects variables that are generally used in risk assessments. In the case of toxicity data, for example, investigations leading to the quantification of a generic variance for between-species variation from pooled data for many pesticides may be useful (Luttik and Aldenberg 1997). 

Methods for evaluating the performance and utility of uncertainty analysis in the context of probabilistic pesticide assessments are needed. This should include comparisons between assessment outputs and existing field data (e.g., avian field studies) to evaluate whether decision makers can rely on the assessment methods. Consideration should also be given to existing field data to refine generic assessment models, using Bayesian updating methods. 

Official government statistics on imports and exports for chemicals such as diazinon are summarized under broad generic categories such as pesticides or organophosphates. In 1982, estimated diazinon imports to the United States were 6.41xl04kg (141,000 pounds) (HSDB 1996). No recent estimates are available on the volume of diazinon imported into the United States. Data on past and/or current import volumes are not adequate to assess trends in import volumes of this pesticide. 

Organophosphorus compounds are used widely as pesticides and some also have other industrial uses. These diagrams shows the generic chemical structures for the major classes of organophosphorus pesticides ... 

Banks, J.N., M.Q. Chaudhry, W.A. Matthews, et al. 1998. Production and characterisation of polyclonal antibodies to the common moiety of some organophosphorus pesticides and development of a generic type ELISA. Food Agric. Immunol. 10 349-361. 

Alcocer, M.J.C., P.P. Dillon, B.M. Manning, et al. 2000. Use of phosphonic acid as a generic hapten in the production of broad specificity anti-organophosphate pesticide antibody. J. Agric. Food Chem. 48 2228-2233. 

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