A decision earlier this week by the U.S. Environmental Protection Agency (EPA) to allow the use of the pesticide chlormequat has brought a strong rebuke from the Environmental Working Group (EWG).

The nonprofit EWG, a non-governmental organization, said EPA’s decision allows the use of “a highly toxic agricultural chemical for use on crops like oats, wheat, and barley grown in the U.S.” If the decision goes final, EWG said it “would mark the first-ever approval for using the dangerous pesticide chlormequat chloride on U.S. food.”

EPA is accepting comments on the decision for the next month, until May 26.

EPA released the proposed decision for public comment for the first food uses of the pesticide chlormequat chloride to provide farmers with an additional tool to help increase crop yield. Before registering these uses, EPA said it must establish tolerances in or on barley, oat, triticale, and wheat.

“The EPA proposal to allow chlormequat to be sprayed on crops that ultimately become the main ingredients in foods we eat, like cereals, is a serious mistake that puts the health and safety of the American public, especially children, at risk,” said EWG VicePresident for science Investigations Olga Naidenko. Ph.D.

“Animal studies show chlormequat can disrupt fetal growth and damage the reproductive system, raising serious concerns about how this chemical could harm human health, especially children,” said Alexis Temkin, Ph.D., EWG senior toxicologist.

“The EPA should put the health and well-being of the public over the narrow, profit-fueled interests of the pesticide industry and big agribusiness operations,” Naidenko added. 

Previously, chlormequat was only allowed for use on ornamental plants in the U.S., but, according to EWG, it still shows up in the U.S. food supply due to chlormequat use on imported grains.

Chlormequat chloride is currently registered for use as a plant growth regulator (PGR) in ornamentals grown in greenhouses and nurseries. This pesticide works to control plant size by blocking the hormones that stimulate growth prior to bloom.

EPA reports that in small grains like wheat, barley, oats, and triticale, lodging (the bending over or breakage of small grain stems) is a major production issue.

According to the agency, lodging can severely limit grain yield and harvestability and have detrimental effects on grain quality. As a PGR, chlormequat chloride application decreases the height of the grain plant stem, resulting in reduced lodging and potentially increased grain yield. Compared to other PGRs with similar use patterns, chlormequat allows for more flexibility in application timing, resulting in greater ease of use for small grain producers.

Before issuing this proposed registration decision, EPA assessed whether exposures to this product would cause unreasonable adverse effects on human health and the environment, as required by the Federal Insecticide, Rodenticide, and Fungicide Act (FIFRA).

based on EPA’s human health risk assessment, no dietary, residential, or aggregate (i.e., combined dietary and residential exposures) risks are of concern. EPA’s ecological risk assessment identified no risks of concern to non-target, non-listed aquatic vertebrates that are listed under the Endangered Species Act, aquatic invertebrates, and aquatic and terrestrial plants.

The agency is proposing mitigation measures to address potential risks of concern to occupational workers as well as birds, reptiles, amphibians, mammals, and terrestrial invertebrates:

• Requiring personal protective equipment such as long-sleeve shirt, long pants, socks, shoes, and waterproof or chemical-resistant gloves to address occupational risks of concern;
• Requiring 24-hour restricted entry intervals, including posting signs at all reasonably expected points of worker entry to the treated area to address occupational risks of concern; and
• Requiring a mandatory and advisory spray drift management statement to address ecological risks of concern.

The proposal is now available for public comment in docket EPA-HQ-OPP-2021-0290 at www.regulations.gov for 30 days and it does close on May 26.