"The search for the killer of America's bees is a little bit like an Agatha Christie novel. Suspicion has turned toward one shady character and then another: declining habitat; parasites; diseases; pesticides.
Or did they all conspire in the recent mass murder of the country's bees?
Today, two new studies are turning the spotlight of suspicion toward a specific class of insecticides called neonicotinoids. It's becoming increasingly clear that these chemicals are present — although at low levels — across huge parts of American farmland. And they may be addling the brains of our bees.
These chemicals came on the market in the late 1990s, and about a decade ago became popular as insect-killing coatings on seeds. Today, most of the corn seed (also canola and sunflower seed) in the country is covered with these insecticides before those seeds are planted. The biggest manufacturer of the pesticides is Bayer CropScience, based in Germany."