The US Environmental Protection Agency has a emergency order this week suspending all use of a herbicide known to cause irreversible developmental damage to human fetuses.
The now-banned pesticide – dimethyl tetrachloroterephthalate, or DCPA, marketed under the brand name Dacthal – stops the growth of certain annual grasses and weeds, and is registered for use on broccoli, Brussels sprouts, cabbage and onions, among other crops, as well as peat. But mounting evidence has shown the chemical is dangerous to humans — “so dangerous that it should be removed from the market immediately,” as Michael Freedhoff, assistant administrator for the EPA’s Office of Chemical Safety and Pollution Prevention, said in a statement.
From Tuesday, farmers will no longer be able to buy DCPA or use up their existing stock. This is the first time in nearly 40 years that the EPA has exercised this emergency authority for a pesticide.
Farmworker unions and advocacy organizations see the decision as a major victory for environmental justice, as pregnant people working on farms can be exposed to DCPA levels between 4 and 20 times higher than the EPA estimates are safe. Almost 80 percent of farmworkers nationally identify as Hispanic, while 70 percent are foreign-born, and 20 percent of farmworker families live below the federal poverty line. Economic insecurity, language barriers and fear of being reported to immigration authorities can make it difficult for farmworkers to return from dangerous working conditions.
“The EPA’s order will protect farmworker women and girls who bear the heavy and dangerous burden of pesticide exposure every day,” Mily Treviño-Sauceda, executive director of Alianza Nacional de Campesinas, an organization of female farmworkers, said in a statement said. statement. “This will spare their children lifelong damage when they grow food to ensure that families across the country have food on their tables.”
The EPA’s decision is the result of a regular review process conducted every 15 years to ensure that registered pesticides “do not cause unreasonable adverse effects on people and the environment.”
For DCPA, the EPA collected toxicity data from the AMVAC Chemical Corporation, DCPA’s sole manufacturer, between 2013 and 2023. After receiving a long-awaited study on the herbicide’s effects on fetal thyroid development, the EPA said last year that there serious health risks to people who handle the chemical or work in areas where it has been used.
Although DCPA product labels warned workers not to enter treated fields for 12 hours after the chemicals were applied, EPA found that in many cases fields remained too dangerous to enter for periods of 25 days or more. A phenomenon called “spray drift,” where pesticides drift from the point of application to other fields or neighborhoods, also posed potentially unavoidable risks to human health.
Ariana Drehsler/AFP via Getty Images
In April, the EPA issued a warning to farmworkers about the “serious, permanent and irreversible health risks” related to DCPA – including concerns that the chemical could cause changes to fetal thyroid hormone levels, which have been linked to low birth weight and impaired brain development, and motor skills. AMVAC voluntarily canceled DCPA registrations for use on grass in December 2023, but the EPA said the company’s proposals to mitigate the chemical’s many health risks were insufficient AMVAC notified earlier this year that it would take regulatory action “as soon as practicable” under the Federal Insecticide, Fungicide, and Rodenticide Act, or FIFRA.
Under less urgent circumstances, this might have meant issuing a cancellation order, but then keeping DPCA on the market for several months or even years while the agency procedural requirements such as gathering input from stakeholders and the public and negotiating with the product manufacturer. In this case, however, the EPA said the risks are so great that it may suspend DCPA while those cancellation proceedings unfold.
The AMVAC Chemical Corporation did not respond to Grist’s request for comment.
Amy van Saun, a senior attorney for the nonprofit Center for Food Safety, praised the EPA’s decision to not only stop the sale of DCPA, but to order companies not to use the Dacthal they already have on hand : “No more selling or transporting unless you” return it to the manufacturer to dispose of,” she said. “If the EPA does a good job of telling everybody that this is happening, that you can’t use it anymore, then farm workers who work around [DCPA] will immediately no longer need to be exposed.”
She added that farmworkers represent the “backbone” of the United States’ agricultural system, but that they have historically been “treated extremely unfairly.”
Anne Katten, director of the Pesticide and Worker Safety Project at the nonprofit California Rural Legal Assistance Foundation, said the suspension would also protect farmworkers’ families. “It’s often very difficult to completely eliminate exposure to home invasion,” she said, explaining how DCPA can cling to field workers’ clothing and follow them home. Farmworkers are generally concerned about exposure to pesticides, Katten added, but they often don’t know which ones have been applied to the fields where they work.
Katten and van Saun said they are now eager to see the EPA use its authority to suspend other toxic pesticides, including paraquat and the herbicide glyphosate — known by the brand name Roundup. Long-term exposure to paraquat, which is banned in the European Union, is linked to Parkinson’s; some studies link glyphosate cancer, as well as liver and kidney damage. In 2021, the EPA ban the pesticide chlorpyrifos after research linked it to neurological damage in children.
“We really encourage EPA to keep doing this,” van Saun said. “We hope they continue to cancel more pesticides that harm people’s health.”
