A federal appeals court Thursday blocked the use of a pesticide over concerns about its effect on honey bees, which have mysteriously disappeared across the country in recent years.
The U.S. Environmental Protection Agency did not adequately study the pesticide sulfoxaflor before approving its use in 2013 on a wide variety of crops, including citrus and cotton, the 9th U.S. Circuit Court of Appeals said.
Initial studies showed sulfoxaflor was highly toxic to honey bees, and the EPA was required to get further tests, Circuit Judge Mary Schroeder said.
"In this case, given the precariousness of bee populations, leaving the EPA's registration of sulfoxaflor in place risks more potential environmental harm than vacating it," she wrote.
EPA spokeswoman Laura Allen said the agency is reviewing the decision but had no further comment.
Sulfoxaflor is part of a group of insecticides known as neonicotinoids (NEE-OH-NIC-DUH-NIDES), according to the 9th Circuit ruling. Neonicotinoids are suspected of being among several factors that have contributed to the collapse of honey bee colonies throughout the U.S.
Bees, especially honeybees, are needed to pollinate crops, and they are considered essential to the U.S. food supply.
But a disorder has caused as much as one-third of the nation's bees to disappear each winter since 2006. A 2013 report issued by the EPA and U.S. Department of Agriculture cited a parasitic mite, multiple viruses, bacteria, poor nutrition, genetics, habitat loss and pesticides as factors for the bees' disappearance.
"We're certainly extremely happy," said Greg Loarie, an attorney with the group Earthjustice, which challenged the EPA's approval of sulfoxaflor on behalf of groups in the beekeeping industry. "It means that sulfoxaflor comes off the market while the EPA does the work it should have done a long time ago."
Loarie said the pesticide was used on cotton in southern states, but it had only been approved on an emergency basis for one crop in California.
The 9th Circuit overturned the EPA's unconditional registration of sulfoxaflor and ordered it to get additional studies and data about the pesticide's effect on bees.
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