We’ve written before about the alarming rate of bee death (or colony collapse disorder) around the world, and last week the British Beekeepers’ Association revealed that one in three of the UK’s honeybee hives failed to survive the winter and spring.

Now, the Natural Resources Defense Council says that a new class of pesticides might be playing a role in bees’ destruction – but the EPA won’t turn over relevant studies. Jane Kay reports in the San Francisco Chronicle:

The Natural Resources Defense Council wants to see the studies that the EPA required when it approved a pesticide made by Bayer CropScience five years ago. …

Clothianidin is the pesticide at the center of controversy. It is used to coat corn, sugar beet and sorghum seeds and is part of a class of pesticides called neonicotinoids. The pesticide was blamed for bee deaths in France and Germany, which also is dealing with a colony collapse. Those two countries have suspended its use until further study. An EPA fact sheet from 2003 says clothianidin has the potential for toxic chronic exposure to honey bees, as well as other pollinators, through residues in nectar and pollen.

The EPA granted conditional registration for clothianidin in 2003 and at the same time required that Bayer CropScience submit studies on chronic exposure to honeybees, including a complete worker bee lifecycle study as well as an evaluation of exposure and effects to the queen, the group said.

NRDC lawyer Aaron Congelo notes that we don’t even know whether the studies were turned in to EPA at all. The organization filed a Freedom of Information Act request with the agency, and followed with the lawsuit when EPA missed the 20-business-day deadline for responding.

It’s unlikely that a particular pesticide is solely responsible for the problem of bees’ death, but it might be a factor. Given how much our diets and economy depend on bees – they pollinate roughly one-third of the human diet, and $15 billion of U.S. crops – it’s worthwhile for government agencies to be tackling this problem from every possible angle.

In fact, NRDC is also asking supporters to send emails from its website to the USDA, urging that agency to take full advantage of the $20 million that it now gets each year for bee research and related work.