Washington State University (WSU) researchers have determined that as many as 25 types of toxic air pollutants — in various combinations — may worsen asthma symptoms and outcomes in low-income, elementary-age children who reside in Spokane.
The study was designed to analyze the effects of 109 air pollutants and their combinations on asthma outcomes. Researchers assessed data from the Environmental Protection Agency (EPA) on air toxins present in neighborhoods surrounding 10 Spokane elementary schools and reviewed reports of students diagnosed with asthma who experienced symptoms such as coughing, wheezing, difficulty breathing and the need to use an inhaler.
“It’s not just one pollutant that can be linked to asthma outcomes. This study examined the variety and combinations of air toxics that may be associated with asthma symptoms,” said lead author Solmaz Amiri, DDes, MSc, a research assistant professor in the WSU Elson S. Floyd College of Medicine in Spokane.
Researchers found that one group of children from a lower-income neighborhood was exposed to 13 of 25 toxic air pollutants. Specifically, the study evaluated asthma symptoms occurring in 2019 and 2020 in the six months before the start of pandemic lockdowns. Researchers associated these data with air pollutant exposures that occurred within those six months and with two, longer-term exposure periods of three years and five years prior to the onset of asthma symptoms.
Three pollutants ranked highest of the 25: a widely used industrial solvent formerly used in household cleaners and glues, a paint additive and an anti-septic and anti-mildew agent that was banned in the 1980s but may still be found in some pesticides and preservatives made before then.
“Some of these air toxics were discontinued in the U.S., but they can still be found in materials that may be in storage or people have in their backyard or garage. Other air toxics still exist at least in the environment,” Dr. Amiri said.
Exposure to such pollutants, Dr. Amiri said, may be due to the proximity of low-income housing to a highway with a lot of traffic or facilities that use solvents, such as paint producers or factories.
