In The Air And Our Lungs: An Up-Close Look At Particulate Matter

On a sunny day in early October, ideastream visited an EPA-regulated air monitoring site in Painesville, Ohio, to understand how air pollution is tracked. The EPA monitors six pollutants across the U.S.: carbon monoxide, lead, ozone, particulate matter, nitrogen dioxide, and sulfur dioxide.

"What I’m holding in my hand are particulate matter filters," said Dan Marn, who works at the Lake County General Health District air monitoring site. "They start off completely white and clean, and this is what it looks like after it’s been in the monitor for several months."

Particulate matter, normally invisible to the human eye, is revealed on these filters. This type of pollution is harmful to human health, particularly respiratory health.

"Pm is particulate matter — it’s the small dust particles that gets deep into your lungs and can actually get embedded in your lungs," said Bert Mechenbier, air pollution control supervisor at the Lake County General Health District.

In Painesville, four pollutants are monitored: sulfur dioxide, ozone, and two different types of particulate matter: pm2.5 and pm10. Many of the monitors run twenty-four hours a day, seven days a week, every day of the year.

"This is a pm dust monitor, and I just come up every three days or within those three days to load a filter into it and set it up to run from midnight to midnight," Marn said.

Most pollution comes from point sources like factories, mobile sources like cars and highways, or even natural sources like pollen or wildfires. Tracking air pollution levels help counties and states maintain EPA standards that keep the air cleaner.