In disappointing news a court recently denied EPA's request to take Dow's Enlist Duo, a combination pesticide, off the market. However, the court's decision still gives EPA the ability to more fully evaluate the effects of Enlist Duo or even to cancel it entirely. Now is the time for the agency to get it right.
Enlist Duo is a next generation pesticide that combines two powerful herbicides - 2,4-D and glyphosate. It is Dow's response to the fact that several varieties of superweeds have evolved resistance to glyphosate (commonly marketed as Roundup) alone due to the overuse of glyphosate in connection with crops that are genetically engineered to resist it. Only it's not a solution at all since more weeds will only develop resistance to this combination of herbicides leading to a snowballing effect of increased herbicide use that threatens the environment and public health.
EPA had requested that the court vacate the registration of Enlist Duo while the agency reevaluated the synergistic effects of the two pesticides on endangered plants. Additionally, as we have argued in court, EPA has never evaluated the effect that Enlist Duo would have on the declining monarch butterfly population and it has not adequately addressed the effects that Enlist Duo would have on public health. In fact, an investigative article in the Chicago Tribune revealed that EPA changed a key finding in their analysis of health effects for 2,4-D, one of the herbicides in Enlist Duo, that allowed for 41 times more of the chemical to enter the American diet than previously had been deemed safe. Furthermore, since EPA originally approved Enlist Duo an international panel of scientists has classified 2,4-D and glyphosate as possible and probably carcinogens respectively.
Although Enlist Duo will remain on the market, EPA still has an opportunity to take a closer look at this next generation pesticide - or even cancel it entirely. The agency has indicated that it is only going to evaluate whether its proposed buffer is sufficient to protect endangered plants growing outside agricultural fields. However, it is within EPA's authority - and in fact, its mandate - to more fully examine the broader effects that widespread use of Enlist Duo would entail - including its effects on monarch butterflies and public health. EPA can and must do more to protect the environment and our health from the harms of Enlist Duo.