A new study by Purdue University scientists seems to confirm what environmentalists have long suspected — that the massive bee die-offs known as Colony Collapse Disorder are linked to pesticides. Specifically, researchers are pointing to a category of pesticide marketed by the German chemical company Bayer.
Multiple methods of poisoning bees
The Purdue research indicates bee deaths are connected to neonicotinoid pesticides, which use a synthetic derivative of nicotine. These chemicals are applied as a coating to corn and soybean seeds prior to planting. They are then absorbed by the plant’s vascular system and expressed through pollen and nectar. Farmers have planted millions of acres of farmland with neonic-treated seeds since 2003.
Bayer has defended its pesticide in the past against charges of contributing to bee die-offs. The company says that bees do not forage much on corn pollen and therefore only trace amounts of neonic-laced pollen will return to hives. The multinational chemical corporation claims the tiny doses of the pesticide bees come into contact with cannot have an impact on hive health. So far, the EPA has supported Bayer’s claims.
The Purdue study, however, shows that Bayer’s products are far more lethal to bees than the company wants regulatory agencies and farmers to believe. The researchers found that, contrary to Bayer’s claim, “maize pollen was frequently collected by foraging honey bees while it was available: maize pollen comprised over 50% of the pollen collected by bees, by volume, in 10 of 20 samples.”
The scientists also identified unsuspected methods by which bees are exposed to the pesticide. Mechanical seed planters blow off a powdery waste as they move through fields. This talc prevents the polymers used to bind the chemicals to the seeds from clogging up seed coating machine and the seed planters. But this exhaust is dangerous to bees. The talc can contain up to 700,000 times the bee’s lethal dosage of neonicotinoid so that foraging bees coming into contact with it are killed. These initial population losses begin to weaken the hives.
As the talc exhaust settles on nearby plants and into the soil, there is a long-term danger to bees. Dandelions near treated crop fields can harbor the poison. Bees gather nectar and pollen from the yellow flowers will bring the neonicotinoids back to the hive. Although these small levels of the pesticide do not kill the bees, their immune systems become compromised, leaving hives vulnerable to other threats. Also, developing bees are affected by exposure to pesticides through stored pollen. The cascading effects of sub-lethal doses can potentially devastate an entire hive. Scientists found neonicotinoid pesticides in every sample of dead and dying bees as well as in pollen the bees collected and brought back to the hives.
Money before honey
US regulatory agencies follow a policy of relying on manufacturer data to determine the safety of a substance. Although a leaked document in 2010 revealed that EPA scientists found Bayer’s research on its neonic pesticides to be suspect, the agency has not acted to stop the sale of these products.
Bayer has profited to the tune of over one billion dollars from its two neonic products imidacloprid and clothianidin. Given Bayer’s deep pockets, it seems unlikely the feds will take action any time in the near future — particularly in a presidential election year. This means Colony Collapse Disorder is likely to continue to devastate bee populations, leaving reverberating effects on the environment for generations to come.
After this type of insecticides were banned in France and Germany, bee populations began to rise again. If you want to join with other citizens in urging decisionmakers to ban bee-killing pesticides, you can sign a petition here: https://secure.avaaz.org/