Wildfire experiment: pollutant exposure of firefighters and forestry personnel during and after the fire

When a wildfire is burning and being suppressed, firefighters are directly exposed to smoke and ash plumes. However, the potential hazard does not end once the fire has been extinguished: forestry workers who subsequently clear access routes, secure deadwood, or prepare the site for reforestation may repeatedly come into contact with ash and contaminated soil. The actual level of pollutant exposure during and after a fire has so far received little systematic investigation for these groups.

This is precisely what we, the Landscape Geoscience Group, are measuring. During the experimental burn and the subsequent mop-up operations, we equip emergency responders, forestry personnel, and volunteer students—acting as “bystanders” to simulate typical spectator exposure—with particle filters and silicone wristbands. The filters capture inhaled fine particulate matter, while the wristbands act as passive samplers for organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) in ambient air—without an active pump, simply through being worn on the body.

In the laboratory, we extract the collected contaminants from the samplers, separate particulate and gaseous fractions, and then determine PAH and heavy-metal concentrations separately. This will, for the first time, enable us to quantify the actual exposure of different groups—from active fire suppression to follow-up work weeks later—and identify the activities and periods that are particularly critical.