CU study finds wildfire smoke exposure increases mental health risk in youth

A new study from the University of Colorado Boulder found that the more a child is exposed to wildfire smoke and other forms of air pollution, the more likely he or she is to experience anxiety, depression and other mental health symptoms.

The study, published in Environmental Health Perspectives, studied 10,000 children ages 9 to 11 across the United States. It looked at the number of days in a given year that each child was exposed to fine particulate air pollution levels above federal Environmental Protection Agency standards for 24-hour air quality.

Fine particulate air pollution is distinct from ozone air pollution, which has been a long-time issue in Colorado. Fine particulate air pollution is produced from any source of fire.

“We know that air pollution is getting better in the United States, due to the Clean Air Act,” said Colleen Reid, associate professor of geography at CU Boulder, who advised the study. “What’s been happening in the western part of the U.S. is that the benefits of the regulation of air pollution from vehicles and air pollution from industry have been offset by the increase in wildfire smoke.”

Evidence already shows associations between fine particulate air exposure and poor cardiovascular outcomes. In the last few decades, research has also started showing a similar effect on mental health.

The study, which collected data in 2016 and included parent questionnaires, also found that the increases in anxiety and depression symptoms remained up to one year later. Data also showed that 32% of participants were exposed to at least one day of particulate exposure at unsafe levels. One participant experienced 173 days of unsafe exposure, according to the study.

The study also indicated differences between racial groups and socioeconomic status groups in terms of mental illness and psychopathology. Harry Smolker, a CU research scientist and the study’s lead author, explained that children in lower income groups may be more likely to live in environments that have high air pollution and have a number of other factors that may be detrimental to mental health that may not be air pollution specifically.

“I think the important point is that even when we control for those differences in sort of demographic and socioeconomic factors, we still saw this association between air pollution levels and symptoms of anxiety and depression,” Smolker said.