WASHINGTON - The emerald ash borer is a prolific tree killer, but researchers suggest the beetle also may have a link to premature deaths in humans.
Since arriving in the U.S. more than a decade ago, the emerald ash borer has destroyed 100 million ash trees.
While the beetle doesn't directly harm humans, researchers have found a troubling link between the destruction of ash trees and public health.
"We found that in counties that were infested with the emerald ash borer, we saw higher levels of cardiovascular lower respiratory disease," says Geoffrey Donovan, a researcher based at the U.S. Forest Service's Pacific Northwest Research Station in Portland, Ore.
"Human interaction with the natural environment is a fundamental part of human health and well-being," he says.
A study published in the American Journal of Preventive Medicine brought attention to the correlation between tree loss and increased mortality.
The study concludes the following:
"Tree loss from the spread of the emerald ash borer is associated with increased mortality related to the cardiovascular and lower-respiratory systems. This relationship is particularly strong in counties with above-average median household income."
"Can we definitively say this is the cause of the relationship? No, we can't. But we can say it's suggestive," Donovan says.
The emerald ash borer is native to China, and scientists say the ash tree co-evolved with it there.
But since arriving in the U.S. in 2002, the beetles have destroyed tens of millions of ash trees that have not developed defenses like the species found in Asia.
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