TABLE 4-1 End Points for Various Toxicity Studies

Study

End Points

Developmental toxicity

Fetus: mortality, growth retardation, skeletal variations, gross external malformations, soft tissue/internal organ defects

Female parent: general toxicity

Reproductive Toxicity

Male parent: general toxicity, effects  on fertility, reproductive organ changes

Offspring: effects on viability, sex ratio, growth, behavior

Carcinogenicity

Tumor development and general toxicity

Neurotoxicity

Behavior, function, and motor activity deficits; microscopic nervous tissue  changes

Mutagenicity

Heritable lesions leading to altered phenotypes

 

SOURCE: EPA, 1984

registration of given product. The list of pesticides for which registration standards have been issued is referred to as List A and can be found in Appendix I of the Federal Register notice of February 22, 1989. Under the FIFRA Amendments of 1988, the data bases on the remaining registered pesticide products are being upgraded in five phases over a 9-year period.

The first sections of this chapter describe in detail the present toxicity testing procedures for pesticides in relation to their registered use patterns and EPA's proposed changes or additions to these procedures. The conclusions and recommendation of the committee for further changes and additions to the toxicity testing battery to allow for more adequate consideration of the special testing needs for infants and children are presented.

CURRENT METHODS: GENERAL CONSIDERATIONS

Toxicity studies are required to assess potential hazards to humans through the acute, subchronic, and chronic exposure of laboratory animals to pesticides. The more specific types of toxicity that are determined include carcinogenicity; developmental (including teratogenicity in offspring) and reproductive toxicity; mutagenicity; and neurotoxicity (Table 4-1). Detailed information on the metabolism or biotransformation of the pesticide is also obtained. Consideration is given to testing individual metabolites in animals, and in or on pesticide-treated plants to which humans could exposed through their diet. The extent of metabolite testing required depends on the level of potential toxicity and environmental persistence of the metabolite. With the exception of



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