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US EPA renews effort to protect endangered species from pesticides

Litigation and statutory deadlines prompt agency to address effects

by Britt E. Erickson
February 27, 2022 | A version of this story appeared in Volume 100, Issue 8

An orange, white, and black bay checkerspot butterfly.
Credit: Josh Hull/USFWS
Pyrethroid pesticides may harm endangered species such as the bay checkerspot butterfly, the Center for Biological Diversity claims.

Less than a week into 2022, the Center for Biological Diversity announced its intent to sue the US Environmental Protection Agency for approving 300 pyrethroid insecticides over the past 6 years without considering harm to endangered species.

Such lawsuits are nothing new for the EPA. Environmental groups have sued the agency repeatedly for decades for failing to comply with the Endangered Species Act (ESA) when registering pesticides. The law requires the EPA to consult with other federal agencies when a pesticide has the potential to harm endangered species or their critical habitats. But the agency rarely initiates such consultations in the absence of litigation.

Pesticide companies are tired of the uncertainty of not knowing whether the courts will impose restrictions on their products. Farmers want assurance that they will be allowed to use the pest control products that they plan to. Environmental groups would prefer to resolve the matter without expensive, time-consuming litigation.

The EPA also seems to be taking the issue seriously now. In June 2021, the agency appointed Ya-Wei “Jake” Li, a lawyer with experience in chemical regulation and endangered species conservation, as deputy assistant administrator for pesticide programs. Li’s top priority is improving the pesticide office’s compliance with the ESA.

To take a large county off limits because there’s some habitat in a few parts of that county may not make sense.
Brett Hartl, government affairs director, Center for Biological Diversity

The EPA is trying “to move past the dysfunction of the past,” says Brett Hartl, government affairs director at the Center for Biological Diversity. The agency is walking a fine line between protecting endangered species and giving pesticide users the tools needed to control pests on food and other crops and in urban environments. The EPA seems “committed to really trying to find practical solutions that strike the right balance,” Hartl says.

In January, the EPA rolled out a policy focused on active ingredients in new pesticides. The agency agreed to evaluate impacts on endangered species for all new pesticides before they hit the market. It also committed to adhere to the ESA by initiating consultations with the US Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) when appropriate.

Chemical structure of 2,4-dichlorophenoxyacetic acid.

Under the new policy, if the EPA finds that a pesticide is likely to adversely affect an endangered species or its habitat, it will require mitigation measures before the product can be marketed.

Chemical structure of atrazine

“Incorporating ESA assessments into the registration process for new pesticides is a key component of EPA’s larger effort to meet the Agency’s ESA obligations efficiently and effectively,” Li said in a Jan. 11 statement announcing the policy.

The EPA has yet to disclose details about that larger effort. The agency declined C&EN’s request to speak with Li, noting that it expects to share more information in a work plan in March.

Environmental groups hope that the plan will address not just new pesticides but also the hundreds already on the market that the EPA has yet to evaluate for risks to endangered species. Most of the litigation related to endangered species has involved older pesticides. The EPA reevaluates the human health and ecological risks of pesticides on the market every 15 years. During that process, the agency is also supposed to consider effects on endangered species.

Under various legal settlements over the last decade, the EPA agreed to evaluate about a dozen high-profile pesticides for their potential to harm endangered species. Those pesticides include the herbicides atrazine and glyphosate, as well as neonicotinoids and the organophosphate insecticides chlorpyrifos, diazinon, and malathion.

In each case, the EPA found that the pesticides are likely to adversely affect several endangered species. But for the most part, the agency has not implemented measures to protect those species.

Hartyl says the atrazine lawsuit did get pesticide makers to phase out the most problematic uses, including canopy spraying, and a few nonagricultural uses. And companies agreed to completely end use of the chemical in Hawaii, which is home to more than 550 endangered species, he notes. “But many other species in the lower 48 states are still at risk. And we need to see conservation measures on the ground to protect endangered species from atrazine,” he says.

The next step is for the Fish and Wildlife Service or the National Marine Fisheries Service to complete their determinations and work with the EPA to put in place measures to address the harms of the chemicals subject to legal settlements. “The Fish and Wildlife Service is failing, quite spectacularly, to finish that work,” Hartl claims.

Given the supply chain is in a very fragile state right now, it’s very hard to come by alternative products this late in the season.
Allison Crittenden, director of congressional relations, American Farm Bureau Federation

The crux of the problem is that the agencies do not agree on how to assess the risks that pesticides pose to endangered species and their habitats. “The EPA and the services engaged in long-running conversations to try to settle on a body of information that would be considered in the risk assessment,” says William Jordan, former deputy director of pesticide programs at the EPA and member of the Environmental Protection Network, a group of former EPA employees. They also aimed “to settle on a methodology for evaluating those data to develop predictions about how much risk the use of a pesticide might pose to listed species,” he says.

After years of discussions, the agencies still use different approaches and have different thresholds, and as a result they end up with big differences in their risk predictions.

In the case of the organophosphate insecticide malathion, the EPA’s evaluation found that nearly all endangered species would likely be adversely affected by the pesticide, while the Fish and Wildlife Service found that less than 5% would be harmed, says Allison Crittenden, director of congressional relations at the American Farm Bureau Federation, an agricultural industry group.

The federation is concerned about the EPA’s new approach to early mitigations before the expert wildlife agencies have reached their determinations. The group claims that the EPA’s models overestimate pesticide usage and therefore overestimate impacts on endangered species. “While we appreciate that this is intended to make the products we use more legally defensible, we want to make sure we’re not being forced to use mitigation that isn’t needed,” Crittenden says.

It is unclear whether the EPA will use the same approach for the hundreds of pesticides already on the market. The agency is facing an Oct. 1 deadline to reevaluate about 1,000 pesticide active ingredients as part of the 15-year registration review process. “EPA has made phenomenal progress,” in conducting ecological and human health risk reviews, says Jim Aidala, senior government affairs consultant at the law firm Bergeson and Campbell. But it is likely to punt the endangered species evaluations for those chemicals to a later date, he says.

The agency did test out the new approach in a decision announced Jan. 11 to reregister Enlist herbicides, including Enlist Duo, which contains a combination of glyphosate and 2,4-dichlorophenoxyacetic acid (2,4-D).

For those registrations, the EPA imposed new mitigation measures to protect endangered species, even though the Fish and Wildlife Service has yet to complete its review. The measures include preventing runoff and prohibiting the use of the herbicides in certain counties where the EPA identified risks to the American burying beetle and other endangered species that live or eat in corn, cotton, or soybean fields.

“If you’re in one of those prohibited counties, you’re in a very challenging situation where you no longer have access to a product that you were potentially planning to use,” Crittenden says. Farmers may have already purchased seed and arranged for delivery of herbicides, she says, “and given the supply chain is in a very fragile state right now, it’s very hard to come by alternative products this late in the season.”

The EPA’s Li and other members of a federal interagency working group heard a lot of concerns from weed scientists, farmers, and state agriculture officials about the countywide Enlist bans during a Jan. 27 public meeting. The commenters called for more accurate locations for species ranges and habitats and smaller pesticide restriction areas.

Hartl, with the Center for Biological Diversity, sympathizes with those concerns. “The goal of this process should be to draw lines on maps that are more refined” and more targeted at areas where endangered species are found, he says. “To take a large county off limits because there’s some habitat in a few parts of that county may not make sense.”

American burying beetle.
Credit: Lindsay Vivian/USFWS
Potential effects of 2,4-dichlorophenoxyacetic acid on the endangered American burying beetle led the US Environmental Protection Agency to prohibit the use of Enlist herbicides in certain counties.

The need to refine endangered species maps was identified as an important gap by the National Academy of Sciences a decade ago, Hartl points out. The Fish and Wildlife Service has been “woefully negligent and delinquent in getting this done,” he says.

Going forward, for the hundreds of pesticides already on the market that are not involved in settlement agreements, as well as new active ingredients, the EPA, the Fish and Wildlife Service, and other federal agencies should get together with environmental groups, pesticide companies, and pesticide users to hammer out an agreement on a prioritization scheme, Jordan says.

Such a scheme should consider both the extent a pesticide is used in areas where endangered species are found and its toxicity to animals and plants, Jordan says. Older, more toxic pesticides would likely be ranked ahead of newer, safer active ingredients, and thus the prioritization scheme would provide more protection than the EPA’s current emphasis on new active ingredients, he says.

And the EPA should use actual pesticide usage data when possible, Jordan adds. The agency’s current policy of using label directions to estimate pesticide exposure to endangered species wildly overstates likely exposure and is not the best available scientific information, he says.

The Center for Biological Diversity is urging the EPA to systematically evaluate pesticides by class for their potential to harm endangered species. In its latest intent-to-sue notice to the EPA, the group suggests starting with pyrethroids because of their acute toxicity to several endangered species.

“Despite pyrethroid pesticides representing one of the most dangerous and harmful groups of pesticides for aquatic wildlife, as well as causing significant harm to other wildlife and plants, the EPA has failed to take a single action to implement any on-the-ground conservation actions to protect any endangered species from these toxic chemicals,” the Center writes in a Jan. 6 letter to EPA administrator Michael Regan.

Stakeholders are generally encouraged that the EPA is talking to parties on all sides of the issue to chart a path forward. But they remain cautious that this will be the year that the agency comes up with a workable plan to address the risks of pesticides to endangered species. Every administration since George W. Bush has attempted to fix this problem, Aidala says. “Many have tried. All have failed,” he says. The Joe Biden administration “is once again trying to roll the boulder back up the hill.”

If the agency fails to address the backlog of pesticides that have not undergone endangered species consultations, “we’ll bring lawsuits class by class to address the violations and force a queue to develop,” Hartl says. “We really do want to make sure that the most important places are protected,” he says, so that there aren’t “spraying or applications happening in a way that pushes species towards extinction.”


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