Chemical giant petitions EPA for wider use of chlormequat. Will government ignore reproductive harm?

Caryn Lipson

March 5, 2024

Story in a flash:

Common cereals are contaminated with chlormequat, a plant-growth regulator that harms animal fertility and development.
The EPA has permitted chlormequat on imported grains. Now, at the behest of industry, the agency wants to allow its use on domestic crops.
Center for Food Safety responds to industry petition for more toxic chlormequat, citing serious reproductive harm.
The EPA denies risks to people from chlormequat-contaminated foods yet acknowledges hazards to occupational workers.
The Environmental Working Group (EWG) believes the EPA is not serving the American people as it should.

Popular cereals contain pesticide associated with reproductive and fetal harm

Although not yet permitted for use on food crops in the U.S., since 2018 the EPA has allowed chlormequat-tainted oats, barley, and wheat to be imported into the U.S. Chlormequat is a plant-growth regulator shown to cause reproductive and developmental harm to animals and their fetuses/offspring.

The Environmental Working Group's (EWG) below chart shows that the pesticide is found in many popular oat-based cereals.

EWG tested people to determine whether the chemical can be found in the body; 90% of the people studied had chlormequat in their urine.

EPA choosing industry over children?

In April 2023 the EPA proposed allowing chlormequat to be used on domestic crops. The EPA wants “to provide farmers with an additional tool to help increase crop yield.” The agency explained how chlormequat works and its potential benefit to farmers:

The pesticide works to control plant size by blocking the hormones that stimulate growth prior to bloom.

In small grains like wheat, barley, oats, and triticale, lodging (the bending over or breakage of small grain stems) is a major production issue. 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. (Emphases added.)

Flowers and ornamental plants are grown by spraying them with chlormequat.

A single spray application of products that contain chlormequat chloride inhibited stem extension of salvia. The spray was made one week after transplant to crops grown at 72° F under a 16-hour day with high light. Photo taken four weeks after application, courtesy of Matthew Blanchard.

In his article “Using Chlormequat Chloride with Success,” associate professor and floriculture extension specialist in Michigan State University’s Department of Horticulture, Erik Runkle explained how to use chlormequat for plant growth. He included the photo at right, to show the difference between plants sprayed with chlormequat, the active ingredient in both Citadel and Cycocel, and the control plant on the left, which was not sprayed.

Runkle also wrote a little about chlormequat's history, explaining that the chemical was first tried on wheat and after on flowers:

The first experiments were performed and published on wheat, in which applications of the chemical produced shorter plants with thicker stems.. . .

The first experiments on floriculture crops . . . showed that the chemical could be used as a drench to inhibit stem extension, increase stem thickness and increase leaf greenness of chrysanthemum and poinsettia.

Chemical company behind EPA's new proposal

The EWG isn't the only organization alarmed by chlormequat's presence in the U.S. food supply. In 2021, Bill Freese, the Scientific Director for the Center for Food Safety (CFS) responded to the EPA's request for comments on a petition by Taminco US LLC, a global specialty chemical company bought by Eastman Chemical Company, urging the agency to increase the permitted uses and tolerance levels of the pesticide:

Taminco US LLC has petitioned EPA to register new uses of the plant growth regulator, chlormequat chloride, on barley, oat, triticale and wheat grains; and to establish new U.S. tolerances for this compound in or on these raw agricultural commodities, as well as in the meat and meat byproducts of cattle, goats, hogs, sheep and poultry, additionally in eggs and milk.

Evidence of harm presented to EPA

Freese cited the following objections to the request for increased tolerance levels:

"Chlormequat chloride is extremely persistent. It is . . . not expected to degrade on the surface of sprayed leaves (EPA 3/26/21). Thus, it is not surprising that it turns up frequently not only in raw cereal commodities, but also in processed cereal products."
It is a low-dose reproductive toxin.
“The risks to human health of exposure far exceed any minor agronomic benefits. However, even if one were to consider some tolerances justified, those proposed by Taminco are far higher than are “needed” to accommodate the intended use of chlormequat to strength stalks of the pertinent grain crops: wheat, barley, oats and triticale.”
“High tolerances encourage bad agricultural practice and increase chlormequat exposure.”
“Co-exposure aggravates adverse effects.” As Freese explained, the increased exposure to the toxin, should Taminco's request be granted, would have additive effects on the exposure to other toxins in the environment.

. . . Low-level co-exposures to multiple chemicals frequently have additive effects on common target tissues, a result which EPA scientists have found sometimes holds true even if components of the mixture have dissimilar mechanisms of toxicity . . .

This means that safety thresholds established for individual substances may well not be protective in the real world of co-exposure to multiple chemicals . . .

He noted that this effect is particularly true concerning male reproduction, even at very low levels of exposure.

This evidence is particularly strong for anti-androgenic compounds. Numerous animal studies show that in utero exposures to mixtures often have additive and occasionally synergistic adverse effects on a range of male reproductive endpoints, even when components of the mixture are administered at levels at or well below the individual NOAELs . . .

As would be predicted from the dose addition principle, EPA research scientists found that the doses of individual chemicals needed to adversely affect male reproductive tract development decrease with increasing number of anti-androgens in the mixture . . .

Freese concluded by stating that sperm counts in men in developed countries have been declining for decades, largely attributable to increased exposure to environmental toxins.

Sperm counts and quality have been declining for decades, with an over 50% reduction in sperm counts in men in developed countries from 1973 to 2011 . . . Scientists attribute this decline in large part to increasing exposure to environmental chemicals, including pesticides . . . (Emphases added.)

EPA denies pesticide has “unreasonable adverse effects on humans”

Before issuing its proposal, the EPA claimed that it assessed chlormequat to ensure that it posed no “unreasonable adverse effects to human health":

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

Based on EPA’s human health risk assessment, there are no dietary, residential, or aggregate (i.e., combined dietary and residential exposures) risks 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. (Emphasies added.)

EPA admits “risks of concern” for humans and animals

However, the EPA seems to have immediately contradicted itself as it also proposed the following 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 an advisory spray drift management statement to address ecological risks of concern.

The following are a few examples of occupational hazards that can occur with chlormequat use:

EPA not in business to protect Americans

EWG's Alexis M. Temkin and Alex Formuzis discussed the agency's findings in the below video. In his conclusion, Formuzis shares his observation that the agency is not serving the American people:

the average American probably believes that the EPA is solely in the business of protecting them and their families from contaminants including pesticides in the foods, but the opposite is actually true.

Temkin concludes by stating what the agency should be doing:

We need the EPA to protect children's health and use the best available science and data to do that.

Want grandchildren? Make different breakfast and snack choices

Parents who desire healthy children and grandchildren may want to reconsider their breakfast meal plans and the snacks they buy and choose other grains not treated with chloremequat.