18-Year Study on Bees Finds Controversial Pesticides Most Harmful

Decades-Long Study on Bees Finds Controversial Pesticides Most Harmful

Solving the mystery of colony collapse disorder—the affliction causing millions of bees to die or abandon their hives—is a bit like identifying the culprit behind autism. But the offender may be one and the same: pesticides, specifically neonicotinoids.

According to new research published earlier this week in the journal Nature Communications, bee colonies exposed to the class of pesticides known as neonicotinoids, or neonics, showed longer term damage and higher risk factors for declining bee populations.

The researchers looked at data collected over 18 years on more than 60 bee species in England. According to the Washington Post, the study “provides some of the first evidence that the effects of neonicotinoid exposure can scale up to cause major damage to bees.”

Bee species who spent more time foraging on crops treated with neonicotinoids were more likely to suffer “severe” losses compared to bees that were exposed to crops not treated with neonics.

Specifically, the researchers looked at data on bees foraging on rapeseed (canola), a crop commonly treated with neonics, and the changes in bee populations after exposure. These were not laboratory settings with high-level exposure, but data taken on real crops treated under approved regulatory guidelines for the pesticides. Bee populations who foraged on the treated rapeseed were three times more likely to vanish or go extinct locally than bees who did not forage the treated crops.

“It’s impossible to say for sure that the neonicotinoids were responsible for this difference, but the results suggest a link,” explains the Post. “The findings support the previous research which indicates that neonicotinoids can have damaging effects on bees — and they also suggest that these effects could result in serious population declines on a large scale in the long term.”

Use of neonicotinoid-based pesticides has been pointed to as a likely cause of colony collapse disorder in recent years. Data on its connection spurred temporary bans on the insecticide in Europe, and discontinued use of it by major home improvement retailers including Home Depot and Lowe’s in the U.S.

“Numerous studies have indicated that exposure to [neonicotinoid] pesticides can have adverse effects in insects they were not intended for, hindering their ability to pollinate or reproduce or leading to increases in mortality,” reports the Post.

And it’s not just insects who suffer from exposure. Numerous studies have pointed to serious human health risks from neonictoniod exposure, including an increased risk of autism. And it’s not just neonics used on crops. A 2014 study out of UNC Chapel Hill and UC Davis found in utero exposure to imidacloprid, a class of neonics used in flea and tick treatments in pets, was linked to a higher risk of autism spectrum disorder in children.

Find Jill on Twitter and Instagram

Related on Organic Authority

Judge Says USDA Must Protect Organic Crops from Pesticide-Contaminated Compost
Controversial Insecticide Significantly Decreases Fertility in Honeybees, New Study Finds
Home Garden Company Ortho Nixes Neonicotinoids to Help Save the Bees

Bee on a canola flower image via Shutterstock