Effects of chronic exposure to biomass pollutants on cardiorespiratory responses and the occurrence of exercise-induced bronchoconstriction in healthy men.

Abstract

Exposure to charcoal biomass (CB) pollutants affects the cardiorespiratory system. We assessed cardiopulmonary responses (CPR) to exercise in charcoal producers (CPs) compared to farmers and evaluated the prevalence of exercise-induced bronchoconstriction (EIB). Forty-five CPs and 36 farmers, healthy males aged 23-39, completed a 15-m Incremental Shuttle Walk and Run Test (15-m ISWRT). Air quality index (AQI) and CO intoxication were measured, CPR was assessed through heart rate (HR), blood pressures (SBP, DBP), and spirometry at rest, peak exercise, and during recovery at 5 and 15 min. Aerobic capacity (VO₂ max) was estimated from the distance covered during the 15-m ISWRT, and EIB was defined as a >10% decrease in FEV1 from baseline values. AQI was worse in charcoal workplaces, and CPs had higher CO intoxication than farmers (p < 0.0001). Both groups reached maximal exercise %HRmax: 84 (82-89) versus 84 (80-89), p = 0.37 and showed similar predicted VO₂ max 36.2 (31.1-43.1) versus 38.9 (32.2-43.7) mL/kg/min, p = 0.60. However, after ISWRT, CPs had lower FEV1 than farmers (2.9 ± 0.6 vs. 3.3 ± 0.6 L, p < 0.003) and slower recovery. EIB prevalence was higher in CPs (60.0% vs. 27.8%, p = 0.006). Chronic exposure to CB increases EIB in healthy CPs, suggesting heightened airway hyperreactivity.