The Effects in the Upper Airway of Heat and Exposure to Combustion Byproducts of Burning Materials on Larynx of Firefighters.

Summary Introduction High exposure to heat and combustion byproducts is associated with health problems and an increased risk of cancer. Objective To study the effects of heat and smoke derived from burning on the upper airway of firefighters. Methods Thirteen firefighters underwent a 4-week training program in Compartment Fire Behavior Training simulators while working with live fire, heat, and smoke from pallets and oriented-strand board sheet burns. The firefighters were evaluated before exposure and at the end of the first and fourth weeks of training. The larynx was assessed by the Voice Handicap Index GRBASI scale, laryngoscopy, and peak expiratory flow. Results There was no change in Voice Handicap Index and GRBASI (only one in three speech therapists judged tension as worse by one point). Laryngoscopy showed alterations in one-third of the firefighters, with the most frequent being increased viscous mucus. Peak expiratory flow decreased significantly from 685 to 552 and 550 L/min in the first and fourth weeks, respectively. Conclusions Although participants were protected from gases and smoke during the exercises, which proved to be very effective, the airway was slightly impacted by heat and combustion-derived byproducts.