Fixing EPA's Pesticide Approval Process: Part 2

EPA should not rely on untested mitigation measures to approve unsafe pesticides

Unsafe pesticides often stay on the market long after it’s clear they harm people’s health and the environment. Congress charged EPA with protecting public health by ensuring pesticide safety, but loopholes in EPA’s pesticide reviews let dangerous chemicals remain in use. In fact, the European Union has already banned (or is in the process of banning) 72 pesticides that are still approved in the United States. This blog is the second in a series that proposes simple, critical reforms to strengthen EPA’s pesticide review process and protect human health and the environment.

Pesticides must be approved by EPA before they can be sold or used. To approve a pesticide, EPA must assess the health and environmental risks it poses and then balance the pesticide’s costs and benefits. We previously wrote about basic flaws in EPA’s cost-benefit assessments, which leads EPA to approve harmful pesticides without accounting for the environmental and economic costs they impose.

There’s another major problem in EPA’s pesticide reviews: EPA routinely assumes without evidence that untested “mitigation measures” will adequately reduce the risks posed by an otherwise unsafe pesticide.

In other words, EPA may decide after completing its health and environmental safety assessments that a pesticide poses unreasonable risks, meaning EPA cannot approve its use without significant restrictions. But EPA often approves the pesticide uses anyway, by imposing mitigation measures that it declares will reduce those risks. And EPA generally does so without evidence to show the mitigation will be effective, let alone that it will reduce risks enough for the pesticide to meet the safety standard set by Congress. Moreover, once a pesticide is approved, EPA has no formal process for circling back to check if its proposed mitigation measures were effective until fifteen years later.

The story of dicamba

A prime example of this practice is EPA’s approval of the weedkiller dicamba. Dicamba is an effective pesticide, but it has a well-known tendency to drift off fields where it has been sprayed, killing trees, crops, and other plants. EPA recognized this harm but approved dicamba anyway, after adopting mitigation measures intended to limit off-field spread. This mitigation included restrictions on spraying dicamba above a certain height or spraying when it was too windy.

The mitigation didn’t work, and state agriculture departments were deluged with complaints that dicamba was killing trees and non-target crops. A court later reversed EPA’s dicamba decision, pointing out that EPA ignored evidence showing its mitigation wouldn’t work. In the meantime, EPA’s dicamba approval caused untold environmental damage and economic harm.

Glyphosate: Another failed mitigation effort

Another prominent example is the pesticide glyphosate, the main ingredient in Roundup weed-killer products. Indiscriminate use of glyphosate threatens both human health and the environment. A recent EPA review agreed glyphosate poses serious threats, including to mammals and birds, terrestrial and aquatic plants, and endangered fish and amphibians.

Rather than restrict glyphosate’s use—or take it off the market—EPA decided that minimal mitigation measures would do enough to ameliorate the risks. The mitigation included only various changes to the label on glyphosate products, like new instructions that EPA hoped would lessen off-site drift and warnings about ecological risks. EPA cited nothing to show that these paltry measures would in fact reduce the acknowledged risks of environmental harm. Indeed, in setting out these mitigation measures, EPA focused on explaining that they wouldn’t reduce total use of the pesticide, not on showing how they would lessen the pesticide’s risks. NRDC and others are challenging this decision in court.

EPA’s regulations do allow it to adopt mitigation measures rather than ban a pesticide outright after identifying health or environmental concerns. But EPA must at least offer a persuasive argument that its mitigation will do the job. At bottom, under EPA’s own rules, any mitigation must “ensure” that a pesticide’s approval satisfies the safety standard in the law. Too often, EPA has no evidence that its mitigation will reduce documented risks at all, let alone prove that the mitigation will ensure safety.

A call for change

Much like EPA’s flawed approach to analyzing costs and benefits of pesticide use, relying on untested mitigation to assume safety allows EPA to approve almost any pesticide, no matter the risks.

EPA must stop approving unsafe pesticide uses based on untested, unproven mitigation. Doing so is not only dangerous; it leaves EPA’s pesticide decisions vulnerable to legal challenge. In two recent cases, courts have reversed EPA pesticide approvals in part because of this shortcoming. More pesticide approvals will be susceptible to reversal in court if EPA continues the practice, wasting agency resources and reducing certainty for pesticide users.

Before greenlighting a pesticide’s use, EPA should require that any mitigation intended to prevent unreasonable risks be proven effective. That would be a stark—and much needed—improvement over EPA’s current process.