Photograph by Chris Johns
Backlit by midnight flames, firefighter Kim McKillop shows the strain of battle in Oregon's Deschutes National Forest. Inhaling smoke on the fire line is part of the job, but researchers are now looking closer at the effects of wildfire smoke. When a forest goes ablaze, it discharges hundreds of chemical compounds, including carbon monoxide. Over time the wear and tear on the human lungs constitutes a serious health risk.