In a press release on August 6, 2024, the EPA announced the emergency suspension of all registrations of DCPA (marketed and sold as Dacthal® herbicide). The full press release can be viewed here: EPA Issues Emergency Order to Stop Use of Pesticide Dacthal to Address Serious Health Risk | US EPA
Why did EPA do this?
EPA determined that exposure of pregnant mothers to DCPA can result in changes to fetal thyroid hormone levels, which in turn can result in low birth weight, impaired brain development, decreased IQ, and impaired motor skills.
EPA determined that even when personal protective equipment is used and the labeled re-entry interval (12 hours) is followed, the risk of exposure to field workers could be greater than 20 times what EPA estimates is safe for unborn babies.
Why did this happen now?
Although this decision seems sudden, the EPA expressed concerns about DCPA in 2013 and requested additional data from the herbicide’s registrant, AMVAC Chemical Corporation. In 2022, EPA issued a notice of intent to suspend production of DCPA, which I wrote about in a Facts for Fancy Fruit article here: Future of Dacthal® Herbicide Uncertain | Purdue University Facts for Fancy Fruit. The EPA suspended the registration of Dacthal® in August of 2023, then lifted the suspension in November of that same year. EPA intends to issue a notice of intent to cancel DCPA products in the next 90 days.
What does this mean?
All use of Dacthal must stop effective immediately.
We will update this information on the eMidwest Vegetable Production Guide database (mwveguide.org) and in future revisions of the Midwest Fruit Pest Management Guide.
Additional information is available in the DCPA registration review docket EPA-HQ-OPP-2011-0374.