Ask the MPCA features questions Minnesotans have asked us, on the issues the agency works on, from waste disposal, water and air quality, and chemicals in products to recycling and reuse, contaminated sites, and septic systems. If you have a question for MPCA staff, submit it via the Ask MPCA online form.
I am looking to buy a home less than 350 feet from a freeway. I am concerned about pollution. There is a small park, wall, and trees between the house and the freeway, which should mitigate it to some degree—but how much effect do these things really have? Can you tell me if there are any results available for air-quality testing near the home?
Air pollution typically is higher the closer you are to roadways. Near-road air pollutant levels and types of air pollutants vary with traffic patterns, roadway design, and vehicle mix.
According to MPCA Air Assessment Section Manager Kari Palmer, “Air pollutants from cars, trucks, and other motor vehicles are found in higher concentrations near major roads. People who live, work, or attend school within about 300 feet of major roads appear to have an increased incidence and severity of health problems associated with air pollution exposures. Research suggests that sound walls, cut sections, and roadside vegetation can reduce traffic-related air pollutants immediately downwind of a roadway, although the extent of this reduction can vary by the dimension and type of feature.”
In 2015, as part of the EPA’s air monitoring network plan, the MPCA installed two near-road monitoring sites in the Twin Cities metro area to measure hourly levels of nitrogen dioxide, carbon monoxide, and fine particles. So far, the near-road monitoring sites have shown that air quality near roadways meets applicable standards, but in many cases pollutants are elevated compared to air monitors farther from the road. Research shows that even low and moderate levels of air pollution can contribute to serious illnesses and early death. (See MPCA's report, Life and Breath: How air pollution affects public health in Minnesota for more information.)
What's more, near-road pollution disproportionately affects people of color, who are more likely to live near busy highways. The Centers for Disease Control estimates that about 4% to 6% of Minnesotans live within 500 feet of a major roadway.
Air sensor technology has advanced significantly and many devices appropriate for general use are available to buy. You could get specific measurements of air quality near your home by investing in such a device. In its Air Sensor Toolbox, EPA scientists evaluate commercially available sensors for how well they measure air pollutants and how easy they are to use.
To learn more about MPCA air-quality monitoring in specific locations, email Kari Palmer.
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