Three widely used insecticides are “likely to adversely affect” the vast majority of threatened and endangered species, according to a new analysis by the Environmental Protection Agency.

The chemicals analyzed are the neonicotinoids clothianidin, imidacloprid, and thiamethoxam, which are widely used on a variety of crops, turf and ornamentals. They also are commonly used as seed treatments, but EPA said it did not have enough data on the extent of that use, so it made conservative assumptions and used “surrogate usage information” to fill in for the dearth of data, it said in responding to comments on the draft Biological Evaluations.

In the final BEs required by the Endangered Species Act, EPA concluded that clothianidin is likely to adversely affect 67% of over 1,700 species and 56% of over 800 critical habitats, thiamethoxam 77% of species and 81% of critical habitats, and imidacloprid 79% of species and 83% of critical habitats.

The findings closely track those in draft BEs released by EPA in August. EPA said the BEs "further the goals outlined in EPA’s April 2022 ESA Workplan to provide practical protections from pesticides for listed species."

The next step in the regulatory process is consultation between EPA and the wildlife agencies responsible for the implementation of the ESA, the Fish and Wildlife Service and National Marine Fisheries Service.

“During consultation, the services will develop [Biological Opinions], which will include their official determinations of whether a pesticide is likely to jeopardize each relevant listed species or adversely modify its critical habitat, and include any additional mitigation measures the services develop in coordination with EPA and stakeholders,” EPA said. “EPA will then implement any necessary mitigation measures to protect listed species, in collaboration with pesticide registrants.”

EPA noted that a “likely to adversely affect” (LAA) determination “means that EPA reasonably expects that at least one individual animal or plant, among a variety of listed species, may be exposed to the pesticide at a sufficient level to have an adverse effect.”

CropLife America emphasized that language in its comments on the evaluations. 

"EPA explained that [the 'likely to adversely affect'] determination 'does not necessarily mean that a pesticide is putting a species in jeopardy,'” CLA said, adding it "continues to advocate for BEs that incorporate more real-world data, since the design of the current BE is highly conservative and therefore over-estimates uncertainties.”

The Center for Biological Diversity, which has filed numerous lawsuits against EPA for failing to comply with ESA consultation requirements, was critical of the agency’s draft analysis of the impact of treated seeds.

“While the EPA has made some effort to assess the exposure to non-target wildlife through neonic-treated seeds, the agency’s methods ultimately fail to adequately assess the impacts to listed species and must be remedied in the final BEs,” the group said in comments submitted in October.

Lori Ann Burd, the center's environmental health program director, said Thursday EPA had continued to "ignore our comments on species that wrongly got 'no effect' findings, like Giant garter snakes, which now due to habitat loss use rice fields as habitat."

She also said EPA found the neonics have no effect on aquatic mollusks, "which makes no sense."

A Syngenta spokesperson said the company had nothing to add beyond CLA's statement. The company makes thiamethoxam.

The American Soybean Association and American Farm Bureau Federation said in a joint release that the BEs "do not incorporate scientific and commercial data that could have provided a more realistic picture of the potential impact of the chemistries on species. For example, nearly all applications of neonicotinoids in soybeans are made as seed treatments, using a minuscule amount of pesticide buried underground where it is far less likely to impact species or habitat."

The Center for Food Safety, which has challenged EPA's "treated article" exemption for neonic seeds, said "species found likely to be adversely affected include the Chinook salmon, Florida panther, Indiana bat, whooping crane, California red-legged frog, Karner blue butterfly, yellow larkspur, and many more."

"Neonicotinoids are known for their toxicity to bees and other insects, but today EPA's assessment demonstrates harms across the spectrum of already imperiled animal and plant life," CFS Science Director Bill Freese said. "The wildlife agencies now must now make the right calls to protect already endangered life from these biocides."

Bayer, which makes imidacloprid and clothianidin, also said the assessments were "based on highly conservative assumptions." 

"EPA’s method includes the highest labeled use rates and maximum usage footprints allowed based on current labels," Bayer said. "In the majority of instances this results in endangered species receiving 'may affect' determinations if the product label simply allows for the use of the product in a county where endangered species are located."

The company also said that "Bayer, grower groups and others will continue to have opportunities to participate in this process to help ensure any new measures proposed by the EPA are fully informed and based on sound science."

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