By Katrina Marland

Smoke from the 2009 Tumblebug Complex Fire in Oregon (Credit: USDA Forest Service)

You don’t have to be a genius to know that wildfires can be very harmful. But we usually think of that damage as being contained to the forest or other areas physically touched by the fires. In reality, the consequences of a wildfire spread far beyond the reach of the flames. Effects of wildfires can be found in the soil, the watershed, the populations of flora and fauna, and more. A new study is helping to quantify that damage in a different, rather more disturbing way.

Led by Fay Johnston of the University of Tasmania, a global team of researchers presented a new study at the 2012 annual meeting of the American Association for the Advancement of Science (AAAS). Their research concludes that the smoke from “landscape fires” — which include wildfires, controlled burns and peat fires — contributed to an average of 339,000 deaths per year from 1997 to 2006. Smoke carries many types of pollutants and makes them easy for people to inhale. This study focused on the impacts of fine particulate matter: tiny particles (2.5 micrometers) that can be inhaled and make their way into sinuses, throats, lungs and bloodstreams. Particulate matter can cause heart attacks, decreased lung function, asthma attacks and a number of other serious problems. It is especially dangerous to the elderly, young children and those with lung or heart conditions.

According to the study, the highest losses were in Sub-Saharan Africa and Southeast Asia, with both regions reaching well more than 100,000 smoke-related deaths per year. The team reached these conclusions by analyzing data from a variety of sources, including satellite data of regions prone to such fires and statistics from the World Health Organization. This study is said to be the first of its kind; while others have studied the effects of fires and smoke, none have focused on estimating the resulting death toll. As climate change continues, scientists agree that the world is likely to see more wildfires, which will mean greater risk to forests and to people.

There is some encouraging news, however. At the same meeting of the AAAS, researcher Michael Brauer of the University of British Columbia presented his own findings: Satellite images, methods of measuring air quality and certain computer models can help keep people, governments and public health officials aware of what areas are most at risk for smoke and what they can do to keep safe. Along with the BC Centre for Disease Control, Brauer is working to find a method of forecasting smoke — predicting where the fires will occur, where the smoke from those fires will drift and what impact it is likely to have on local populations.

As sobering as these new statistics are, it’s reassuring to know that as we continue to learn more about the full impact of fires, scientists are already adapting to the new information to develop ways to preserve life.