The Department of Natural Resources reports air-quality readings in the unhealthy range across wide areas of the state today. This is the third day of the high readings for “particulate air pollution,” according to air-quality specialist Brian Button.Button says most often the alerts are in eastern Iowa because it’s close to “dirtier air” from parts of the country farther east, but there have been unhealthy air levels recorded in just about every part of the state. Button says it’s hard to get away from the pollution when the wind’s blowing. He says air pollution can reach high levels anywhere — winds carry pollutants that cause it out over the ocean or in national parks and wilderness area, since it can travel hundreds of miles. Today’s high readings were over eastern Iowa again but also include much of north-central and northwestern Iowa. It’s blamed on a thermal inversion, a layer of air close to the ground that holds smoke and other emissions close to the ground.