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The regulatory responsibilities assigned to the U.S. EPA are complex, and have 

 grown dramatically in recent years without commensurate funding. Many of the 

 provisions of the proposed legislation under consideration today will require new 

 and expanded activities on the Agency's part, and should be funded accordingly. 



Perhaps as a consequence of growing regulatory demands, the Agency has had lit- 

 tle opportunity to create a systematic strategy in the area of pesticide research and 

 development. Yet the Agency has made substantial and pioneering contributions to 

 this field, notably on the issues of developmental and neurotoxic effects of pesticides, 

 pesticide contamination of groundwater, protective clothing for pesticide workers, 

 and residential pesticide exposure. 



The potential for a comprehensive pesticide research program exists within the 

 Agency, and this legislation can provide the impetus for its development. Such a 

 program must increase both in-house capabilities as well as stimulate and sustain 

 basic and applied extra-mural research. 



Need for Research in Pesticide Exposure Assessment 



Federal regulatory policy has become increasingly dependent on risk assessment 

 as a basis for prioritization and decision-making. Risk assessments require the an- 

 swers to two fundamental questions: How and to what extent are particular popu- 

 lations exposed? What are the health consequences of such exposures? In case after 

 case the conduct of sound risk assessments are stymied by lack of adequate expo- 

 sure assessments. 



Farmers and agricultural fieldworkers are exposed to a wide variety of pesticides 

 over an entire growing season, yet exposure assessment studies of these populations 

 are at a rudimentary stage, providing at best an estimate of exposure over a few 

 days for selected compounds. Critical issues such as the magnitude of dermal expo- 

 sure and absorption or the adequacy of protective clothing are to a great extent un- 

 documented. 



Lawns, gardens and the insides of homes are treated routinely with pesticides, yet 

 virtually no data are available to estimate exposures of residents. Children, in par- 

 ticular, may be a sensitive subpopulation. Little information exists to predict the 

 long-term health effects of exposures during infancy or early childhood. We have 

 learned from studies of lead exposure that a primary source for children's exposure 

 is soil and house dust, and that hand-to-mouth activity is an important component 

 of the exposure pathway. The Agency's Office of Research and Development has 

 demonstrated recently that household soils and dust contain a wide range pes- 

 ticides. What hazards do these residues pose to children? How do other pathways 

 (air, food, water) contribute to the multimedia exposures that are the realities of ev- 

 eryday life? How can we minimize exposure in these circumstances? 



The science of exposure assessment is rapidly evolving to take its place as one 

 of the primary environmental health sciences. There is a critical need for basic re- 

 search regarding human exposure pathways and for training young scientists in this 

 field. This legislation clearly recognizes these needs and will help the focus the 

 Agency's attention on these issues. 



Need for Research in Pesticide Toxicology 



Major uncertainties exist regarding both the acute and chronic health effects of 

 pesticides. Basic toxicological research is required in two areas: development of 

 standard methods for testing health effects, and elucidation of mechanisms of tox- 

 icity. 



The neurotoxicity of pesticides has been the subject of growing concern, and the 

 Agency recently published guidelines for neurotoxicity testing. The absence of such 

 guidelines until this time has been due primarily to a lack of standardized tests. 

 Substantial research is required to create and validate testing methods, yet such re- 

 search has received only limited funding. In the case of immunotoxicity, no standard 

 tests are yet available. Thus, pesticides are currently registered with no knowledge 

 of effects on the immune system. Only a substantial investment of time and re- 

 sources can improve our ability to detect subtle and complex responses to such tox- 

 ins. 



