When most people think about air pollution, they think of summertime haze, traffic or smokestack exhaust, wintertime inversions, or wildfire smoke.

They rarely think of the air that they breathe inside their own homes.

In a new study of indoor air quality, a team of WSU researchers has found surprisingly high levels of pollutants, including formaldehyde and possibly mercury, in carefully monitored homes, and that these pollutants vary through the day and increase as temperatures rise. Their study, led by Tom Jobson, professor in the Department of Civil and Environmental Engineering, and graduate student Yibo Huangfu, was published in the journal, Building and Environment.

Researchers know that air pollution, whether inside or outside, has a significant impact on people’s health, including their heart, lungs, brain, and neurological health. But, while the government has increased regulation of outdoor air pollution over the past 40 years, there is little regulation of the air in people’s homes. Building laws generally require that homes are structurally sound and that people are comfortable — with minimal impacts from odors and humidity.

“People think of air pollution as an outdoor problem, but they fail to recognize that they’re exposing themselves to much higher emission rates inside their homes,” Jobson said.

These emissions come from a variety of sources, such as building materials, furniture, household chemical products, and from people’s activities like cooking.

One of the ways to clear out harmful chemicals is with ventilation to the outdoors. But, with increased concern about climate change and interest in reducing energy use, builders are trying to make homes more airtight, which may inadvertently be worsening the problem.

Read more at Washington State University