A pair of pollutants emerged from climate change is to be blamed for most of the nasal allergies to some 50 million people in America, says researchers from Max Planck Institute for Chemistry in Germany.
The two gases are nitrogen dioxide and ground-level ozone, which appear to set off chemical changes in some airborne allergens, increasing their potency.
“Scientists have long suspected that air pollution and climate change are involved in the increasing prevalence of allergies worldwide,” said the institute’s Ulrich Pöschl. “Our research is just a starting point, but it does begin to suggest how chemical modifications in allergenic proteins occur and how they may affect allergenicity.”
Pöschl’s team found that ozone (a major component of smog) oxidizes an amino acid that sets off chemical reactions that ultimately alter an allergenic protein’s structure. Meanwhile, nitrogen dioxide (found in car exhausts) appears to alter the separation and binding capabilities of certain allergens.
Researchers believe that together, the two gases make allergens more likely to trigger the body’s immune response, especially in wet, humid and smoggy conditions.
The team hopes to identify other allergenic proteins that are modified in the environment and examine how these affect the human immune system.