Dimethyl Sulfoxide in Pesticide Formulations; Exemptions From the Requirement of a Tolerance
Key claim: EPA is allowing dimethyl sulfoxide (DMSO) to be used as a solvent in pesticides on crops, harvested produce, animals, and food-contact surfaces without setting maximum residue limits.
Abstract
(Rule · Environmental Protection Agency) This regulation establishes exemptions from the requirement of a tolerance for residues of dimethyl sulfoxide (CAS Reg. No. 67-68-5) when used as an inert ingredient (solvent/cosolvent) in pesticide formulations applied to growing crops or to raw agricultural commodities after harvest, in pesticide formulations applied to animals, and in antimicrobial formulations applied to food-contact surfaces in public eating places, dairy-processing equipment, and food- processing equipment and utensils. Spring Regulatory Sciences on behalf of Gaylord Chemical Company, LLC submitted a petition to EPA under the Federal Food, Drug, and Cosmetic Act (FFDCA), requesting establishment of exemptions from the requirement of a tolerance. This regulation eliminates the need to establish maximum permissible levels for residues of dimethyl sulfoxide when used in accordance with the terms of those exemptions.
Why this matters
Tolerance exemptions for inert ingredients like DMSO let pesticide manufacturers formulate products without triggering separate residue testing or labeling for that component, keeping formulation costs and compliance burden down. For farmers and consumers, the practical effect is indirect — DMSO can appear as a solvent carrier in a wider range of crop, livestock, and food-contact pesticide uses without a numeric residue cap, based on EPA’s safety finding.