"A bee has far poorer recognition of an altered floral mix," said study co-author Tracey Newman. "The bee needs to learn the unadulterated version, and if the bee has learned it, it will then struggle with the version that has been chemically altered."
Though the researchers focused on the effects of nitrogen oxide gases on floral odors, other highly reactive contaminants, such as naturally occurring ozone gas, which is toxic only when present close to the ground, may have a similar effect on floral volatiles, the researchers said.
These findings could have serious implications for the global food supply, the team said, since honeybees pollinate about 70 percent of crop foods across the world, which accounts for about 35 percent of the global food supply.
Global honeybee populations have dramatically declined within the past decade or so due to a condition called colony collapse disorder, which has been associated with the spread of synthetic pesticide use and other manmade materials, but remains poorly understood.