Publications : 2019

Adams R, Brickel J, Bhat VS. 2019. Chemical-specific maximum allowable levels for pesticide residues in dietary supplements. Food Chem Toxicol 123:511-519.


Dietary supplements are regulated by the U.S. FDA as a subset of foods. Most botanical dietary ingredients do not have pesticide tolerances, resulting in the enforcement of zero tolerance or general maximum residue limits (GMRL), rather than utilizing science-informed tolerances. In the current study, chemical-specific maximum allowable levels (MALs) were derived for 185 pesticides by converting existing, authoritative-body human health effects criteria. MALs were derived for 96% of pesticides using criteria established by the U.S. EPA. If multiple authoritative-bodies had established human health effects criteria, the most scientifically-defensible criteria was selected, taking into consideration both carcinogenic and non-carcinogenic endpoints. Five pesticides (o-phenylphenol, pirimicarb, oxadixyl, tetradifon, o,p’-DDT), lacking criteria established by the U.S. EPA had criteria established by other authoritative-bodies that were utilized in the derivation of MALs. Two pesticides did not have any established human health effects criteria (o,p’-DDD and o,p’-DDE). In total, MALs were derived from existing criteria for over 98% of the pesticides in the present study. Consequently, it is demonstrated that human health effects criteria derived by authoritative-bodies can be effectively utilized to derive chemical-specific, science-informed MALs applicable to all food commodities, including botanical ingredients, thereby, minimizing reliance on precautionary zero tolerance and GMRLs.