Meeting with FMC and Exponent on PBPK models for Dimethoate and Malathion.  On October 21, 2019, representatives of FMC and Exponent met with HED and PRD to provide an update on their physiological based pharmacokinetic (PBPK) models for dimethoate and malathion.  These models may be useful in refining the EPA's human health risk assessments by allowing model derived points-of-departure and the estimation of data-derived extrapolation factors (DDEFs) in place of the standard, default interspecies uncertainty factor.  It is anticipated that FMC and Exponent will provide the models to EPA for review by late 2019 or early 2020.  (Kent Fothergill, 703-347- 8299; Carolyn Smith, 703-347-8325)

