USA – The U.S. Environmental Protection Agency (EPA) has issued an emergency order suspending all registrations of dimethyl tetrachloroterephthalate (DCPA), commonly known as Dacthal.

This marks the first time in four decades that the EPA has invoked an emergency order to halt the use of a pesticide.

The decision follows years of efforts by the agency to obtain data necessary for a comprehensive risk assessment of Dacthal, highlighting the urgent concerns over its potential health risks.

Dacthal, a widely used herbicide, has been employed in both agricultural and non-agricultural settings. It is primarily applied to produce crops such as broccoli, Brussels sprouts, cabbage, and onions.

However, mounting scientific evidence has raised alarms about the pesticide’s impact on human health.

Research has shown that exposure to Dacthal during pregnancy can disrupt fetal thyroid hormone levels, which may result in low birth weight, hindered brain development, decreased IQ, and impaired motor skills in children.

Concerns over the safety of Dacthal prompted the EPA to take swift action under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

“DCPA is so dangerous that it needs to be removed from the market immediately,” stated an EPA spokesperson.

The suspension aims to prevent further harm as the agency works to assess the full extent of the pesticide’s risks.

A history of delayed compliance

The emergency suspension comes as Dacthal undergoes a registration review—a routine process that reassesses registered agricultural chemicals to ensure they pose no unreasonable threats to human health or the environment.

The review process for Dacthal has been marred by delays, largely due to the failure of its sole manufacturer, AMVAC Chemical Corporation, to submit essential data required by the EPA.

In 2013, the EPA issued a Data Call-In (DCI) to AMVAC, demanding over 20 studies to support Dacthal’s existing registrations. These studies, which included critical research on thyroid development and function, were initially due by January 2016.

Despite this, AMVAC failed to submit the necessary data, with some of the studies being deemed insufficient by the EPA. Key studies on thyroid effects and other areas remained unsubmitted for nearly a decade.

Steps toward resolution

In response, the EPA issued a notice of intent to suspend technical-grade DCPA in April 2022, citing AMVAC’s failure to provide the required data.

Although AMVAC submitted the thyroid study in August 2022, the company’s continued non-compliance on other fronts led to the suspension of the pesticide’s registration after an administrative hearing.

By November 2023, the suspension on data submission was lifted following AMVAC’s submission of sufficient data. However, the saga continued into May 2023, when the EPA released its assessment on the risks posed by DCPA.

The agency’s analysis of the newly submitted thyroid study revealed health risks associated with both occupational and residential exposure to the pesticide, even when protective measures were employed.

In March 2024, the EPA notified AMVAC that it would explore regulatory options, including the potential cancellation of Dacthal’s registration or an emergency suspension. These options were considered urgent as the agency evaluated the potential risks to public health.

Sign up to receive our email newsletters with the latest news updates and insights from Africa and the World HERE.