WASHINGTON— Three neonicotinoid insecticides likely harm all of the country’s 38 protected amphibians and roughly three fourths of all other endangered plants and animals, according to long-anticipated studies released today by the U.S. Environmental Protection Agency.

Neonicotinoids are the most popular insecticides used in the United States. Hundreds of studies have shown they play a major role in population-level declines of bees, birds, butterflies and freshwater invertebrates. Today’s draft biological evaluations represent the first time the EPA has evaluated the chemicals’ potential to harm the nation’s most imperiled plants and animals.

“Now the EPA can’t ignore the fact that these popular insecticides are wiping out our country’s most endangered plants and animals,” said Lori Ann Burd, environmental health director at the Center for Biological Diversity. “Neonicotinoids are used so widely, and in such large quantities, that even the EPA’s industry-friendly pesticide office had to conclude that few endangered species can escape their toxic effects.”

The EPA’s draft biological evaluations analyzed three neonicotinoids: clothianidin, imidacloprid and thiamethoxam.

Nearly 80% of all endangered species — 1,445 different kinds of plants and animals — are likely to be “adversely affected” by imidacloprid, and the pesticide will adversely modify the designated critical habitats of 658 species. For thiamethoxam, 1,396 (77% of all) endangered species are likely to be adversely affected, and the pesticide will adversely modify the designated critical habitats of 644 species. About two thirds of all endangered species, 1,225, are likely to be adversely affected by clothianidin, and the pesticide will adversely modify the designated critical habitats of 644 species.

“The EPA doesn’t need any more proof. It should ban neonicotinoids right now,” said Burd. “We’re in a heartbreaking extinction crisis, and neonicotinoids are playing an outsized role in driving it. Pollinator populations are declining nationwide. The American bumblebee, once the most common bumblebee in the country, has declined by an estimated 89% in just the past 20 years. There are more Starbucks stores than monarch butterflies in California. What will it take for the EPA to act on this information and ban these deadly chemicals?”

Neonicotinoids are used on hundreds of millions of acres of U.S. agricultural land. They can be directly sprayed or injected and are very commonly used as coatings on seeds planted on hundreds of millions of acres each year. As systemic insecticides, they’re absorbed by plants, making the entire plant deadly, including its nectar, pollen and fruit. They can persist in soil for years.

Species found to be harmed by all three of the neonicotinoids include rusty patched bumblebees, whooping cranes, Chinook salmon, northern long-eared bats and orcas.

Imidacloprid is also one of the two active ingredients in Seresto flea collars, implicated in the deaths of more than 1,700 family pets and under consideration for cancelation following a petition from the Center.

Authors of a major scientific review of the catastrophic decline of insects have said that a “serious reduction in pesticide usage” is key to preventing the extinction of up to 41% of the world’s insects in the next few decades.

For decades the EPA has steadfastly refused to comply with its obligations under the Endangered Species Act. It was finally forced to do this evaluation under the terms of legal settlements with the Center for Food Safety and the Natural Resources Defense Council.