EPA acts to halt approval of Dow’s Enlist Duo herbicide

The US Environmental Protection Agency (EPA) has asked a court to cancel the registration of Dow AgroSciences’ controversial herbicide Enlist Duo, following new information suggesting that ‘synergistic effects’ between the product’s two active ingredients, glyphosate and 2,4-D, could result in greater toxicity to non-target plants. In a 24 November legal action, the EPA sought a remand from the court in order to reconsider the registration.

Dow had not provided this information before the EPA approved Enlist Duo a little over a year ago. The agency says the new details – which indicate that the 30-foot buffer included in the herbicide’s registration may be inadequate – could lead to a different decision on the restrictions for using Enlist Duo.

If the court does overturn Dow’s registration of Enlist Duo, the EPA will issue a cancellation order to address the sale, distribution, and use of any products already available.

Dow says that the EPA has not previously used observations of potential synergy in mixtures as a basis for regulatory action. Although the company says it remains confident in ‘the extensive data’ supporting the technology, it acknowledges that some changes could be made to use conditions on existing Enlist Duo labels.