Air Pollution and Mental Health

A recent study conducted by researchers at the University of Washington has found a link between psychological stress and toxic air pollution. In fact, the higher the level of particulate matter in the air, the more negative impact it has on mental health.

Published in the November issue of the journal, Health and Place, the study relied on 6,000 contributors to a large, national survey, The Panel Study of Income Dynamics. Questions relevant to the UW study measured participants’ feelings of sadness, nervousness, and hopelessness and were scored on a standard scale to assesses psychological distress.

Researchers then compared air pollution database records corresponding with the neighborhoods of the survey’s participants. Through these comparisons, the research team was able to pinpoint fine particulate matter from vehicle exhaust, wood stoves, and power plants as having the highest detrimental effect on psychological and emotional wellbeing.

Fine particulate matter is microscopic, measuring less than 2.5 micrometers in diameter. It is easily inhaled and then absorbed into the bloodstream. Once in the bloodstream, it can have long-lasting effects on the body. Because it passes so easily into the bloodstream, it is a greater risk to human health than larger airborne particulates.

The study discovered that psychological stress increased in proportion to the concentration of fine particulates in the air. Areas that experienced elevated levels of air pollution (21 micrograms per cubic meter or higher) incidents of psychological distress were 17 percent higher than in areas with low pollution levels (5 micrograms per cubic meter or less). For every 5 microgram increase in fine particulate matter, there was a similar effect to a loss of a year and a half of education.

Health professionals have been aware of the negative effects of air pollution on cardiovascular health, as well as lung diseases like asthma. However, the area of how brain health is affected by air pollution is fresh territory.

“On the plus side, air pollution is a health problem with a clear solution,” said Anjum Hajat, an assistant professor of epidemiology at the University of Washington’s School of Public Health. “There is a lot to be said for having federal guidelines that are rigorously enforced and continually updated. The ability of communities to have clean air will be impacted by more lax regulation.”