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The US government is allowing the use of an insecticide linked to declines in bees on two crops that attract bees.

The insecticide, made by Dow AgroSciences, is not approved for general use on crops that attract bees because of concerns about its effect on vulnerable bee populations. But the US Environmental Protection Agency (EPA) has granted exceptions to that rule.

This month, the EPA issued an “emergency exemption” for the insecticide sulfoxaflor for the fourth year in a row. This time, it permits farmers to spray sulfoxaflor on million acres of cotton and sorghum—crops that attract bees—across 18 US states, mostly to control aphids and tarnished plant bugs. The filing also includes exemptions for a number of other insecticides. Exemptions are often used when a pest has been found to have gained a resistance to another common option.

Sold under the brand names “Closer” and “Transform,” sulfoxaflor was banned in 2015 following a lawsuit brought by beekeepers, environmental groups, and honey-industry advocates. A federal court voided an earlier government approval, citing the “precariousness of bee populations” and “flawed and limited data” provided by Dow about sulfoxaflor’s effects. France also suspended the approval of sulfoxaflor after a 2017 court decision citing possible harm to bees.

Dow first marketed sulfoxaflor as a more bee-friendly alternative to neonicotinoids, a class of insecticides that chemically resemble nicotine and have been implicated in colony collapses. However, research found sulfoxaflor functions very similarly to neonicotinoids. A paper published in Nature in August 2018 found that exposure to sulfoxaflor significantly lowered bees’ ability to reproduce. Exposed colonies had fewer than half the number of offspring as unexposed colonies.

“Sulfoxaflor exposure could lead to similar environmental impacts as neonicotinoids if used on crops that attract bees in the absence of evidence-based legislation,” the authors wrote. The EPA had previously classified sulfoxaflor as “very highly toxic” to bees, according to Environmental Health News; the agency now describes it as having “low residual toxicity” to bees.

After the 2015 court ruling, the EPA re-approved the insecticide in 2016, this time including a ban on applying it to crops that attract bees until after their bloom period. But the EPA administrator has the power to grant exceptions in emergencies, permitting the application of the insecticide on crops that do attract bees (like sorghum and cotton) in specific states.

The practice of granting emergency exemptions for pesticides was criticized last year by the EPA’s inspector general’s office, which said “deficiencies have existed for nearly a decade” in the EPA’s collection of data on health and environmental effects (pdf).

The Center for Biological Diversity, an environmental advocacy group, described use of sulfoxaflor “in a time of global insect decline” as “beyond the pale.”

“The routine abuse of emergency exemptions has to stop,” Nathan Donley, a senior scientist with the center, said in a statement.

The abundance of insects globally is on the decline and 40% of species are threatened with extinction. While some wild bee populations are doing well, others have experienced precipitous declines in recent years. The rusty-patched bumble bee, for example, has declined 91% in two decades. Managed honey-bee populations are also in distress, with yearly colony losses well above twice the rate considered normal. Insecticide use is among the mix of factors thought to be causing the declines.

In October 2018, Dow submitted an application to expand the use of sulfoxaflor to rice fields, avocado trees, household plants, tree farms, and greenhouses.