EPA Issues Seldom-Used Emergency Order to Suspend Registrations of Pesticide DCPA
For the first time in almost 40 years, EPA has issued an emergency order under section 6(c)(3) of the Federal Insecticide, Fungicide, and Rodenticide Act to suspend the registrations of all pesticide products containing the active ingredient dimethyl tetrachloroterephthalate (DCPA).
The emergency measure is based on DCPA’s thyroid effects in fetuses, which EPA deemed so severe that continued use of DCPA during the time period required to cancel its registrations would pose an imminent hazard. According to EPA, thyroid hormone perturbations linked to DCPA “can lead to downstream health problems such as low birth weight, impaired brain development, decreased IQ, impaired motor skills, and decreased bone deposition.”
Occupational exposures to DCPA can be over twice as high (as a factor of body weight) as the level at which the thyroid effects were observed in mouse fetuses, and the herbicide’s residues present risks of concern even 30 days after application to crops, EPA said. DCPA is also registered for non-agricultural uses, including on golf courses and athletic fields.
American Vanguard Corporation (AMVAC), the sole registrant of DCPA, voluntarily canceled all but two of its DCPA products and their use on turf. It also voluntarily ceased sale and distribution of the only remaining end-use product until EPA approved product labels that would address DCPA’s risks. However, EPA “determined that there is no combination of practicable mitigations under which DCPA use can continue without presenting an imminent hazard.”
DCPA is currently undergoing registration review, which occurs every 15 years. EPA assessed DCPA’s health risks in 2023 after AMVAC submitted a study on its thyroid effects and other information requested by the agency.
The agency intends to issue a notice of intent to cancel DCPA registrations within 90 days of the order, which was published on August 7, 2024.
Also known by its trade name Dacthal, DCPA is used on a variety of crops for weed control. According to EPA, the emergency order will have a negligible impact on produce prices but may impact growers of crops including bok choy, collards, kale, green onions, and leeks.
Update:
On August 28, 2024, EPA announced that it is initiating a voluntary cancellation of DCPA after AMVAC notified the agency of its intent to cancel the remaining pesticide products. According to EPA, AMVAC also intends to cancel its international registrations.
