The levels of two air pollutants linked to climate change, nitrogen dioxide and ozone, could be helping the number of allergies to rise, a study led by Ulrich Pöschl of the Max Planck Institute in Germany has shown. Pöschl and his team found that the two greenhouse gases cause birch pollen allergens to become more potent, especially in hotter, more humid conditions.
“Scientists have long suspected that air pollution and climate change are involved in the increasing prevalence of allergies worldwide,” says Pöschl. “But understanding the underlying chemical processes behind this phenomenon has proven allusive. 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.”
They found that ozone, the main component of smog, reacts with an amino acid called tyrosine in the pollen, making it a more potent allergen. Nitrogen dioxide from car exhausts can also alter the chemistry of the allergens. Together the two effects may make humans more likely to suffer from allergic reactions, the researchers say.
The team plans to research other allergens to further study the effects. Until then, those who suffer from airborne allergies will have to put up with the sniffles.