For several years, Tom Theobald, a beekeeper in Boulder, Colo., has been trying to check out his suspicions that a relatively new class of pesticides has been interfering with the normal breeding and development of his stock.
The pesticides, based on the chemistry of nicotine, are generically called neonicotinoids. They are applied to seeds of crops like corn and soybeans. When the plants grow, the pesticides, which have been marketed under the names Clothianidin and Imidacloprid, permeate all of the plants’ systems.
Mr. Theobald discovered, and later reported, that the pesticides had been banned in Italy and in Germany, the home country of their manufacturer, Bayer, which reaps hundreds of millions of dollars in revenue annually from their sale. Yet the Environmental Protection Agency gave the pesticides provisional approval several years ago based on a peer-reviewed field study.
That study is itself facing questions. Most pertinently: Are its results relevant to bee populations in the United States, particularly those near the abundant acreage of corn treated with the pesticide?
Word of Mr. Theobald’s research clearly made it to the E.P.A. Late last year he obtained a Nov. 2 memorandum by agency scientists saying that a new field study should be undertaken along with at least one other study to ensure that the Clothianidin, now widely used on crops in the country’s agricultural centers, is not harmful to pollinators.
Bayer officials put up a post in December that said in part, “Clothianidin is the leading seed treatment on corn in the United States and has been used extensively for over six years without incident to honeybees.”
This week Mr. Theobald got reinforcements from two very different quarters. First, Senator Robert Menendez of New Jersey sent a letter to Lisa P. Jackson, the E.P.A. administrator, that said in part:
While large farming operations import managed honeybees for pollination, farmers with smaller, polyculture farms in New Jersey rely heavily on about 350 native species of bees.
Alarmingly, several species of bumblebees are believed to have already vanished and next to nothing is known about the health of other native species of bees.
Among his questions were: What steps is the E.P.A. taking to clarify and assess the risks to pollinators from chronic, sub-lethal neonicotinoid exposure, for example, when insecticide treatments involve seed coatings or injections into root systems? How will its risk assessment account for the accumulation of neonicotinoids in soil over the years?
Then The Independent newspaper in Britain reported on Tuesday that the Department for Environment, Food
and Rural Affairs, the British equivalent of the E.P.A., was reconsidering its benign attitude toward neonicotinoids.
A British scientist who advises the agency, Robert Watson, had pointed out that recent laboratory studies indicate that the pesticide makes bees more susceptible to a dangerous viral infection.
The journalist Tom Philpott took note of The Independent’s report this week at the environmental Web site Grist, which also reported on the E.P.A. scientists’ concerns in December.
Senator Menendez’s office released a statement on Friday saying that native bumblebees “mean big business for New Jersey — creating farming jobs and securing our food supply.”
“They are simply too essential not to understand basic threats to their existence,” it continued. “We must improve our understanding of the risks these chemicals pose to all bees.”