[EPA Pesticide Update posted April 13, 2023]. The U.S. Environmental Protection Agency (EPA) has established the first pesticide tolerance for hemp. This tolerance is for the pesticide ethalfluralin. After a robust human health risk assessment, on April 10th, EPA issued a final tolerance rule that established the maximum amount of ethalfluralin residues allowed to remain in or on hemp seed. Today, EPA accepted labels for this pesticide that now contain directions for use on hemp. Establishing a tolerance for residues of ethalfluralin on hemp and accepting updated pesticide labels provides farmers with an additional tool to control annual broadleaf and grassy weeds that grow in hemp fields.  

EPA is responsible for regulating the pesticides used to protect crops grown for human food and animal feed and for setting limits on the amount of pesticides that may remain in or on foods marketed in the United States. These limits on pesticides left on foods are called “tolerances.”  

Under the Federal Food, Drug, and Cosmetic Act, any person can file a petition with EPA requesting that the agency establish tolerances for a pesticide’s use on a crop.  

The 2018 Farm Bill authorized the production of hemp, and removed hemp and hemp seeds from the Drug Enforcement Administration’s schedule of Controlled Substances. The changes in the legal status of hemp led to increased interest in growing the crop and in pest control options for hemp growers. There are currently biopesticides already registered for use on hemp. However, those pesticides are tolerance exempt because the risk assessments EPA conducted demonstrated that the risks from aggregate exposure to pesticide residues under reasonably foreseeable circumstances would pose no harm to human health.  

Ethalfluralin, a conventional pesticide, is an herbicide that already has tolerances for use on other crops such as peanuts, potatoes, and soybeans. In October 2020, EPA received a petition from Interregional Research Project No. 4 (IR-4) requesting tolerances be established for residues of ethalfluralin in or on several crops, including hemp. IR-4 is a USDA-funded project that helps specialty crop growers address pest management concerns. As this is the first instance of establishing a food tolerance for hemp, EPA considered the agronomics of hemp production and developed science policies to guide assessment of potential human health exposure and risk from application of ethalfluralin on hemp. The final tolerance rule issued this week established tolerances for residues of ethalfluralin for hemp as well as well as other commodities that were part of the subject petition. 

EPA’s tolerance for residues of ethalfluralin in or on hemp seed is based on carefully considered scientific rationale using ethalfluralin residue field trial data from several other crops. This new use of ethalfluralin on hemp is not expected to pose any unreasonable risks to people or the environment.  

To learn more, view the final rule and scientific analysis in docket EPA-HQ-OPP-2021-0130 at www.regulations.gov.