Air pollution kills floral scents makes bees inefficient foragers, study finds

A new study that modeled how air pollution affects bees found that even moderate amounts of pollution can make foraging less efficient.

To find food, bees follow the wafting scent plumes that flower patches emit. But air pollutants, like ozone, hydroxyl radicals, and nitrate radicals, change and degrade the fragrance.

“What we found was those compounds that are the most sensitive to pollutants, if those are being used as the insect attractantm, then it becomes a lot more difficult for insects to find flower patches,” said T’ai Roulston, an author of the study and researcher at the University of Virginia. 

“We are perhaps confusing the insects,” said Jose Fuentes, professor of atmospheric science at Pennsylvania State University and another study author.

Inefficiency feeding can increase the energy expended on feeding and time away from the nest. The team of researchers doesn’t yet know how this affects colonies, but say predators and parasites may be a greater problem.

And humans aren’t off the hook either, said Fuentes. “If we are meaningfully confusing the insects then we are impacting even people in a very direct way. There’s one thing we need to remember: that insect pollinators basically pollinate about 60 percent of the food we humans consume,” he said.   

The air pollution studied often originates in cities. Last year, Philadelphia received a failing grade for ozone from the American Lung Association. And while the pollution could threaten bee populations and urban biodiversity, it would also have far reaching effects in rural and agricultural zones.