EPA Bans Pesticide Linked to Lifelong Harm for Pregnant Farmworkers' Children

For the first time in 40 years, the Environmental Protection Agency has taken emergency action to ban the use of a pesticide linked to serious health problems for fetuses.

The weed killer called dimethyl tetrachloroterephthalate, or DCPA, is manufactured only by one company, AMVAC Chemical Corporation, based in California. It is registered for use on crops such as broccoli, cabbage, cauliflower, Brussels sprouts and strawberries.

“This is a big deal, and sad at the same time,” said Tracey J. Woodruff, professor and director of the Environmental Research and Translation for Health (EaRTH) Center at UC San Francisco, who said the ban was “a long time coming.”

The EPA has repeatedly asked AMVAC to submit data on studies to evaluate the impact of the chemical, but it didn’t do so — for 10 years, according to the agency.

“People were continuing to be exposed, particularly farmworkers,” Woodruff said.

Mark Weller, campaign director for the organization Californians for Pesticide Reform, called it “outrageous that it took more than a decade after the manufacturer, AMVAC, was supposed to submit their study on thyroid damage.”

Throughout that time, pregnant farmworkers exposed to crops treated with DCPA were at the most serious risk, according to the EPA, which said the pesticide could result in lifelong health effects for their children due to changes to fetal thyroid hormone levels — linked to low birth weight, impaired brain development, decreased IQ and impaired motor skills.

“Thyroid hormones are really important during fetal development,” Woodruff said.

The emergency order comes 15 years after the pesticide was banned in the European Union.

“In California, for example, there are more than 130 pesticides banned or not approved by the EU that are applied in ag[ricultural] fields every year,” Weller said. In Santa Cruz County, where Weller lives, “two-thirds of all the pesticides applied by pounds are banned in the EU,” he said.

According to the emergency order, AMVAC has attempted to address these concerns, but the EPA determined there is “no combination of practicable mitigations under which DCPA use can continue without presenting an imminent hazard.”

“DCPA is so dangerous that it needs to be removed from the market immediately,” Michal Freedhoff, assistant administrator for the Office of Chemical Safety and Pollution Prevention, said in a statement released by the EPA. “It’s EPA’s job to protect people from exposure to dangerous chemicals. In this case, pregnant women who may never even know they were exposed could give birth to babies that experience irreversible lifelong health problems.”

AMVAC did not respond to a request for comment.

Weller also sees an unjust process of pesticide regulation on the county level. After the EPA warned states over a year ago that the allowable uses of DCPA “could expose pregnant women to levels 1,500 times above what EPA considered safe,” he said, states could have taken protective action. “They didn’t. They sat on their hands. Even at the county level, farmworker communities asked for help.”

In Monterey County, where Weller said half of all DCPA in California is applied, the environmental justice group Safe Ag Safe Schools requested the county agricultural commissioner implement a one-mile safety zone around schools, but the commissioner refused.

Going forward, Woodruff would like to see the EPA act quickly when the negative impacts are clear.

“What we’ve seen with federal regulation of pesticides is that they tend to not be moving swift enough,” Woodruff said. “It’s good that the EPA is acting on the data. I want to see this for all chemicals.”