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Determination of the Appropriate FQPA Safety Factor(s) in Assessing Pesticide Tolerances

A primary consideration in implementation of the Food Quality Safety Act (FQPA) safety factor provision is assessing the degree of concern regarding the potential for pre- and postnatal effects. In many cases, concerns regarding pre- and postnatal toxicity can be addressed by calculating a reference dose or margin of exposure from the pre- or postnatal endpoints in the offspring and when traditional uncertainty factors are applied to account for deficiencies in the toxicity data.

In some instances, however, data may raise uncertainties or a high concern for infants or children which cannot be addressed in the derivation of an reference dose or margin of exposure. OPP intends to analyze the degree of concern and to assess the weight of all relevant evidence for each case. This involves examining the level of concern for sensitivity/susceptibility and assessing whether traditional uncertainty factors already incorporated into the risk assessment are adequate to protect the safety of infants and children, as well as the adequacy of the exposure assessment.

The guidance also explains how data deficiency uncertainty factors will be used to address the FQPA safety factor provision’s expressed concern as to the "completeness of the data with respect to... toxicity to infants and children...." 

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