WASHINGTON, DC, August 8, 2024 (ENS) – For the first time in almost 40 years, the U.S. Environmental Protection Agency is taking the emergency action of suspending all registrations of a pesticide under the federal Insecticide, Fungicide and Rodenticide Act, warning of health risks to fetuses in the womb.
The agency is stopping registrations of the weed killer dimethyl tetrachloroterephthalate, known as DCPA or Dacthal, following several years of unprecedented efforts by the Biden-Harris Administration to require the submission of long-overdue data and then assess and address the risk this pesticide poses.
EPA has taken this action because fetuses whose pregnant mothers are exposed to DCPA, sometimes without even knowing the exposure has occurred, could experience changes to fetal thyroid hormone levels, and these changes are generally linked to low birth weight, impaired brain development, decreased IQ, and impaired motor skills later in life. Some of these changes may be irreversible, the agency warns.
“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.
“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,” Freedhoff said.
“Farmworkers face burdensome conditions in the fields and often face exposure to harmful pesticides while working to feed our nation. I applaud the emergency action by the EPA which prioritizes farmworker health and safety, especially for pregnant women, by suspending this harmful chemical from our agricultural systems. We must continue to build on this progress and ensure all farmworkers are given the protection, worker’s rights, and overtime pay they deserve,” said Congressman Raúl Grijalva, who represents Arizona’s 7th District.
DCPA is a pesticide registered to control weeds in both agricultural and non-agricultural settings. It is primarily used on crops such as strawberries, cotton, field beans and vegetables such as broccoli, Brussels sprouts, cabbage and onions.
DCPA is currently undergoing registration review, which requires reevaluating registered pesticides every 15 years for adverse effects on human health or the environment.
Mily Treviño Sauceda, executive director of Alianza Nacional de Campesinas, a group led by women farmworkers, said her organization is “pleased to see the EPA make this historic decision.”
“As an organization led by farmworker women, we know intimately the harm that pesticides, including dimethyl tetrachloroterephthalate (DCPA or Dacthal), can inflict on our bodies and communities. 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,” Sauceda said.
“The EPA’s decision to finally suspend DCPA is welcome news, but it’s long overdue,” said toxicologist Alexis Temkin, Ph.D. with the nonprofit Environmental Working Group. “For years, EWG and other public health advocates have warned about the serious risks the weed killer poses to farmworkers, pregnant people and other vulnerable populations.”
A Backstory of Effort and Evasion
In deciding whether to issue the August 6 Emergency Order, EPA consulted with the U.S. Department of Agriculture to understand how growers use DCPA and alternatives to this pesticide.
In 2013, the EPA issued a Data Call-In to AMVAC Chemical Corporation of Newport, California, the sole manufacturer of DCPA, requiring it to submit more than 20 studies to support the existing registrations of DCPA. AMVAC Chemical Corporation is a wholly owned subsidiary of American Vanguard Corporation, also based in Newport.
The required data included a comprehensive study of the effects of DCPA on thyroid development and function in adults and in developing young before and after birth, that was due by January 2016. Several of the studies that AMVAC submitted from 2013-2021 were considered insufficient to address the request for data, while the thyroid study and other studies were not submitted at all.
In April 2022, EPA issued a rarely used Notice of Intent to Suspend the DCPA technical-grade product used to manufacture end-use products based on AMVAC’s failure to submit the complete set of required data for almost 10 years, including the thyroid study.
While AMVAC submitted the required thyroid study in August 2022, EPA suspended the registration based solely on AMVAC’s continued failure to submit other outstanding data on August 22, 2023, following an administrative hearing.
In November 2023, the data submission suspension was lifted after AMVAC submitted sufficient data. Most DCPA use on turf was voluntarily canceled by AMVAC in December 2023, but unacceptable risks from other uses remained.
In May 2023, EPA released its assessment on the risks of occupational and residential exposure to products containing DCPA, following its analysis of the thyroid study finally submitted by AMVAC. The assessment found health risks associated with DCPA use and application, even when personal protective equipment and engineering controls are used.
The most serious risks are to unborn babies. EPA estimates that some pregnant individuals handling DCPA products could be subjected to exposures four to 20 times greater than what the agency has estimated is safe for fetuses in the womb.
Also of concern are risks to pregnant individuals entering or working in areas where DCPA has already been applied, especially post-application workers who are transplanting, weeding and harvesting while pregnant.
Current product labels specify that entry into treated fields must be restricted for 12 hours after application. But the evidence indicates that for many crops and tasks, levels of DCPA in a treated field remain at unsafe levels for 25 days or more, EPA said.
Spray drift from pesticide application – the movement of pesticide through the air at the time of application or soon after, to any site other than the area intended – could also put at risk the unborn babies of pregnant people living near areas where DCPA is used.
Since the release of EPA’s 2023 assessment, AMVAC has proposed several changes to the DCPA registrations, including the cancellation of DCPA products registered for use on turf. Those cancellations practically eliminate exposures to DCPA from recreational activities on and around turf.
But according to EPA’s analysis, AMVAC’s proposed changes to agricultural uses of DCPA do not adequately address the serious health risks for people who work with and around the pesticide.
In April 2024, EPA issued a public warning regarding the significant health risks to unborn babies of pregnant individuals exposed to DCPA and its intent to pursue action to address the serious, and in some instances, permanent, and irreversible health risks associated with the pesticide as quickly as possible.
In a letter to AMVAC dated March 27, 2024, EPA restated the risks the agency found and noted that the agency would be pursuing regulatory options as soon as possible which could include canceling the pesticide or seeking an emergency suspension.
When serious risks are identified, EPA can take action to suspend or cancel a pesticide. Taking such action is resource and time intensive, partly due to the procedural requirements of FIFRA.
A cancellation proceeding takes at least several months, if uncontested by the registrant, or potentially several years, if contested by the registrant, triggering an administrative hearing and any appeal of a cancellation order.
The federal Insecticide, Fungicide and Rodenticide Act, FIFRA, also allows EPA to seek a suspension of a pesticide product while cancellation proceedings are ongoing if the Administrator determines it is necessary to prevent an imminent hazard.
EPA Administrator Regan has determined that, due to the serious and imminent harm posed by DCPA, such an emergency exists. EPA intends to issue a notice of intent to cancel the DCPA products within the next 90 days.
The Emergency Order is effective immediately. EPA determined that the continued sale and use of DCPA products during the time it would take to follow the normal cancellation process poses an imminent hazard to the unborn. While AMVAC has attempted to address these concerns, EPA has determined there are no practical mitigation measures that can be put in place to allow DCPA’s continued use.
Additional information is available in the DCPA registration review docket EPA-HQ-OPP-2011-0374.
Featured image: Pregnant farmworkers in a California field. (Photo courtesy Migrant Clinicians Network)
