Dacthal (DCPA) Pesticide

Dacthal, chemically known as dimethyl tetrachloroterephthalate (DCPA), is a herbicide that controls weeds in various environments. Introduced in 1958, Dacthal targets annual grasses and broad-leaved weeds without harming many sensitive plants like flowers, fruits and vegetables. Consumers commonly apply it to crops such as broccoli, Brussels sprouts, cabbages and onions, as well as on golf course turfs, sports fields and gardens.

The herbicide works by inhibiting weed growth before seeds can germinate. Farmers can apply Dacthal to crops in several forms, including as a spray or granules, and it remains effective in various agricultural settings. However, it can persist in soil for extended periods, sometimes leading to residue on subsequent crops.

Despite its effectiveness, Dacthal has raised health concerns due to its potential risks. According to the EPA, recent research has linked it to serious health issues, including congenital disabilities and other developmental problems among children whose parents experienced Dacthal exposure while pregnant.

This risk has led to increased scrutiny and regulatory actions. In August 2024, the Environmental Protection Agency (EPA) issued an emergency order banning the sale and all uses of Dacthal due to these concerns. The European Union banned it in 2009.

“Farmworkers face burdensome conditions in the fields and often face exposure to harmful pesticides while working to feed our nation,” Arizona Congressman Raúl Grijalva said of the EPA ban. “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.”

Where Was Dacthal Most Widely Used

Dacthal was widely used across the United States, particularly on fruit and vegetable crops. Its use was prominent in the following areas:

These regions were key in the application of Dacthal because they are major vegetable-producing areas.

Below are the types of crops that farmers commonly treated with Dacthal.

The Environmental Protection Agency (EPA) banned Dacthal (DCPA) in August 2024 due to the severe health risks it posed, particularly to fetuses and embryos. The herbicide was found to cause significant health problems.

“Pregnant women who may never even know they were exposed could give birth to babies that experience irreversible lifelong health problems,” said Assistant Administrator for the Office of Chemical Safety and Pollution Prevention Michal Freedhoff. “It’s EPA’s job to protect people from exposure to dangerous chemicals.”

According to the EPA, Dacthal’s widespread agricultural use poses significant health risks, particularly for fetal development and thyroid function. The agency’s decision to suspend Dacthal is the culmination of decades of regulatory oversight.

The ban was a critical step to prevent further harm, according to the EPA. The agency’s emergency suspension aimed to protect farmworkers, pregnant people and consumers from the pesticide’s dangerous effects. This ban reflects a significant shift in regulatory enforcement.

How Dacthal May Cause Birth Defects

Studies have linked Dacthal to severe health risks, especially for pregnant people. Exposure to Dacthal can disrupt fetal thyroid hormone levels, leading to severe congenital disabilities and lifelong health problems. It can effectively “close the skull” before the brain has fully developed, leading to cognitive impairment.

The EPA found that even small amounts of the weed killer DCPA can harm fetuses. Exposure levels as low as 1 mg/kg/day can disrupt thyroid hormones in baby rats, potentially leading to serious health problems in developing babies. Pregnant individuals exposed to DCPA in agricultural or residential areas are at risk. The EPA’s 2023 assessment highlighted significant health risks to embryos and fetuses.

Dacthal is a concerning herbicide that persists at dangerously high levels in the environment for 25 days or more after application, posing prolonged exposure risks to farmworkers and nearby communities. The EPA states that pregnant farmworkers who come into contact with DCPA by using it or handling the sprayed crops may experience exposure levels four to 20 times higher than what the agency deems safe for fetuses.

If you believe your baby suffered birth defects due to Dacthal exposure during pregnancy within the last ten years, it’s critical to take these immediate steps:

Lastly, support groups or online communities can offer emotional support and practical advice for navigating the challenges ahead.

Editor Lindsay Donaldson contributed to this article.