Exposure to Pesticides May Be Factor in Bee Die-offs, Study Says

Exposure to high levels of mite-killing chemicals and crop pesticides may be a factor in the unprecedented die-off of honeybees across the United States and Canada in recent years, according to a new study. Researchers at Pennsylvania State University say tests of beeswax and pollen samples taken from hundreds of beehives contained numerous chemicals toxic to the insects. According to the study, being published in the journal PLoS ONE, the beeswax samples yielded an average of eight pesticides per sample. The average pollen sample contained seven contaminants, with one containing 31. Scientists say the results reveal a possible cause of the mysterious malady known as “colony collapse disorder,” in which foraging bees never return to their hives, leaving their brood and queen to likely starvation. Colony collapse disorder destroyed nearly 35 percent of U.S. honeybee population between 2006 and 2009 and has also afflicted colonies in Europe. Many of the foraging worker bees that leave their hives and are exposed to chemicals may die before they return to the hive, the study said.