WHY ALLERGIES FLARE UP AFTER SPRING STORMS

While spring is a favourite season for many of us with its beautiful blooms and fresh breezes, for those with pollen allergies it can be a time of intense irritation. Affecting nearly one-third of the world’s population, allergies are caused by certain antibodies that bind to allergens (such as pollen and animal hair), and trigger a reaction that releases an array of molecules that cause allergic symptoms of varying degrees. Common symptoms of pollen allergy include nasal congestion, sinus pressure, itchy and watery eyes, decreased sense of taste and smell and bluish-coloured skin beneath the eyes. University of Iowa researchers report that tree pollen fragments remain in the air for as many as 11 hours after heavy rains, and those granules can make their way deep into the lungs, potentially exacerbating allergies. The researchers based their findings on measurements of pollen fragment concentrations during and after rains of varying severity in spring of 2019. “Our results show that while pollen grains decrease substantially during rain events, peak concentrations of submicron pollen fragments also occur and then persist for several hours,” says Elizabeth Stone, an associate professor in the university’s Department of Chemistry. “People who are sensitive to pollen in season should avoid going outdoors during rain events, especially thunderstorms, and for several hours afterward.”