Climate change may increase people's exposure to an outdoor fungus that can damage airway cells, leading to a rise in asthma and allergy symptoms, a new study contends.
The widespread fungus, called Alternaria alternata, produces spores in the dry, warm weather of late summer and early fall, said the researchers from the University of Minnesota and the Mayo Clinic in Rochester, Minn.
Previous research has shown that the fungus produces up to three times more spores when atmospheric carbon dioxide (CO2) levels are high. Rising CO2 emissions are thought to contribute to climate change.
In some people, exposure to the spores can trigger allergy symptoms and asthma, the researchers explained.
For this study, the research team exposed cells from the linings of human airways to Alternaria and found it produced more cell damage. They warned that climate change might intensify the problem.
The study was published online recently in the American Journal of PhysiologyCell Physiology.
"These results suggest that continuing increases in atmospheric CO2 associated with global climate change will increase both the level of Alternaria exposure and antigenicity [the ability to produce an immune response] of spores that come in contact with the airways," the researchers wrote in a journal news release.