‘Dangerous’ Pesticide That Could Harm Fetuses Is Pulled From the Market in Historic Move by EPA

Citing threats to fetuses, the Environmental Protection Agency (EPA) this week issued an emergency suspension of all registrations for a pesticide used on crops to control weeds. The move marks the first time in almost 40 years that the agency has used this kind of action.

Pregnant farmworkers exposed to dimethyl tetrachloroterephthalate, also called DCPA or Dacthal, can experience changes to fetal thyroid hormone levels, which in turn is linked to low birth weight, impaired brain development, lower IQ and impaired motor skills later in the child’s life, the EPA said in a statement on Tuesday. Some individuals who handle DCPA products can be exposed—sometimes without knowing it—to 4 to 20 times the amount considered safe for unborn babies.

The agency says it intends to issue a notice to cancel DCPA products within the next 90 days, but a cancellation proceeding can take from months to several years if the registrant contests it, per the EPA. To act more quickly, the agency decided to issue an emergency order that immediately suspends DCPA’s use because of the health risks it poses to fetuses.

“DCPA is so dangerous that it needs to be removed from the market immediately,” Michal Freedhoff, an EPA assistant administrator, says in the agency’s statement. “Pregnant women who may never even know they were exposed could give birth to babies that experience irreversible lifelong health problems.”

Jeannie Economos, coordinator of the pesticide safety and environmental health program at the Farmworker Association of Florida, tells the Washington Post’s Maxine Joselow and Amudalat Ajasa that the EPA’s order came decades too late for workers who have already been exposed to DCPA.

“It shouldn’t have taken this long, but we are glad that they did it finally,” she says to the publication. “How many people got sick in the meantime? How many babies were born with low birth weight? We don’t know.”

DCPA is used both in agricultural and non-agricultural settings, but it’s mostly applied to crops including broccoli, Brussels sprouts, cabbage and onions, per the EPA. It’s also a possible carcinogen and has been banned in the European Union since 2009, according to NBC News’ Denise Chow.

The pesticide is manufactured solely by the AMVAC Chemical Corporation, which is based in California. In 2013, the EPA requested the company submit more than 20 studies on the safety of DCPA—but AMVAC did not submit some, and others were deemed insufficient. In August 2023, ten years later, the EPA suspended DCPA registrations, since AMVAC still had not submitted some of the required research, specifically a study on thyroid development. The suspension was lifted a few months later after the company submitted the data.

Then, an assessment released by the EPA last year found that DCPA use and application posed health risks, even when personal protective equipment and engineering controls were being used. Workers aren’t allowed to enter fields for 12 hours after DCPA has been sprayed, but the agency found the chemical’s levels can remain unsafe for 25 days or more.

AMVAC voluntarily canceled the use of DCPA on turf last December, but the EPA found the company’s proposed changes in agriculture would not do enough to address health issues for farmworkers.

The EPA issued a public warning on the health risks of DCPA in April, prior to Tuesday’s emergency suspension.

“This emergency decision is a great first step that we hope will be in a series of others that are based on listening to farmworkers, protecting our reproductive health and safeguarding our families,” Mily Treviño Sauceda, executive director of Alianza Nacional de Campesinas, the National Farmworkers Women’s Alliance, says in the EPA’s statement.

“The EPA’s decision to finally suspend DCPA is welcome news, but it’s long overdue,” Alexis Temkin, senior toxicologist at the Environmental Working Group, a nonprofit advocacy organization, tells the New York Times’ Hiroko Tabuchi.

Will Sullivan | | READ MORE

Will Sullivan is a science writer based in Washington, D.C. His work has appeared in Inside Science and NOVA Next.