EPA Issues an Emergency Ban on Dacthal

A man sprays a pesticide on plants in his garden (Photo – agscience.org.nz)

The U.S. Environmental Protection Agency (EPA) has issued an emergency ban on Dacthal, also known as DCPA, due to its severe health risks, especially for pregnant individuals.

By Michael Siegel

Dacthal is an herbicide used on grasses and crops to control weeds, however, there have been concerns for decades on its potential toxicity. The EPA first classified Dacthal as a “Possible Human Carcinogen” in February 1995, and since 2013 had been requesting toxicity data from AMVAC, the manufacturer.

AMVAC, despite a January 2016 deadline, finally released results in 2022 from a thyroid study in pregnant rats after the EPA ramped up pressure. Using this study, the EPA then assessed the human health risks of DCPA exposure and found a threat to fetal thyroid hormones, which could lead to issues like low birth weight and impaired brain development in babies.

Assistant Administrator for the Office of Chemical Safety and Pollution Prevention, Michal Freedhoff, said:

DCPA is so dangerous that it needs to be removed from the market immediately. 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. That’s why for the first time in almost 40 years, EPA is using its emergency suspension authority to stop the use of a pesticide.”

Impact

The impact of this emergency order will be immediate, affecting the use of Dacthal in various applications. While the manufacturer, AMVAC, has attempted to address the EPA’s concerns, it has been determined there are no practical mitigation measures that would allow DCPA’s continued use.

Research has shown that Dacthal exposure is widespread, with studies finding traces of the herbicide inside homes located miles away from agricultural fields. It has also shown to have higher levels of PFAS, also known as Forever Chemicals.

“This pesticide is far too dangerous to be used near residences, schools and fields where workers are tending crops,” said Anne Katten, CRLA Foundation Pesticide and Work Health and Safety Specialist. “We applaud EPA for taking this important step.”