Air pollution may be supercharging common airborne allergens

Thursday, March 30, 2017, 7:14 PM - Have you noticed your allergies getting worse, or that more people are suffering from them, from year to year? According to research, air pollution and climate change may be to blame.

At the 249th National Meeting & Exposition of the American Chemical Society, which took place in Boulder, CO, researchers presented evidence that air pollutants - specifically ground-level ozone and nitrogen dioxide - are capable of altering some of the most common and potent allergen around, making them even more potent.

"Our research is showing that chemical modifications of allergenic proteins may play an important role in the increasing prevalence of allergies worldwide," Christopher Kampf, one of the researchers involved in the study, said in a press release. "With rising levels of these pollutants we will have more of these protein modifications, and in turn, these modifications will affect the allergenic potential of the protein."

The researchers used laboratory tests and computer models to show how a potent allergen protein, called Bet v 1 (found in the pollen of the major white birch), reacts various concentrations of ozone (O₃, one of the two main components of smog) and nitrogen dioxide (NO₂, which is part of vehicle exhaust).

Their model showed that if ozone oxidizes tyrosine, an amino acid that goes into making Bet v 1, it can result in a series of chemical reactions that ultimately links Bet v 1 proteins together. These longer proteins are potentially stronger allergens, since our immune system will will find them more irritating. At the same time, though, according to what the lead researcher, Ulrich Pöschl of the Max Planck Institute in Germany, told the Washington Post, these reactions also make the proteins more susceptible to bonding with nitrogen dioxide.

When NO₂ bonds with the Bet v 1, it alters some of the protein's basic characteristics, which can provoke an even stronger response from our immune system, especially in warmer and more humid conditions, when smog tends to be worse.

According to the researchers, this alteration by air pollution, along with changes to Earth's climate (higher temperatures, increased humidity and longer growing season) may provide an explanation for why more people are suffering from allergies to pollen these days, and it may point to many more sufferers in years to come.

"Scientists have long suspected that air pollution and climate change are involved in the increasing prevalence of allergies worldwide. But understanding the underlying chemical processes behind this phenomenon has proven elusive," says Ulrich Pöschl, Ph.D., of the Max Planck Institute in Germany, who led the study, according to NewsWise. "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."

Sources: NewsWise | Washington Post