Quantifying wildfires exposure for investigating health-related effects

Abstract A wildfire is an uncontrolled fire in an area of combustible vegetation that occurs in the countryside or a wilderness area. The United Nation International Strategy for Disaster Reduction estimates that between 3 and 4 million km 2 are affected by wildfire annually, with 18 000 km 2 occurring in Europe. The Mediterranean region is one of the most affected regions by wildfires in Europe. Nearly 500 000 ha, on average, are burned annually by 50 000 wildfires in the countries of southern Europe bordering the Mediterranean Sea. Wildfires or biomass burning seriously damage ecosystems and affect public health. A major difficulty related to the assessment of health impact of wildfire emissions derives from the complexity of wildfire exposure assessments. Based on the literature, several methods, including satellite data, chemical transport models and, less often, personal exposure monitoring are available. However, few investigations have used methods allowing separating wildfires emissions from air pollutants emissions from urban sources having the same components. An inventory of wildfires occurred in Europe between 2006 and 2010 was obtained in terms of burnt areas, duration and related emissions of major air pollutants (black carbon, particulate matter), as obtained using a hybrid model that allows excluding anthropic sources of air pollution.