Objectives: To investigate the traffic-related PM2.5 and black carbon (BC) exposures and assess their health effects.
Methods: Personal exposure to PM2.5 and BC levels were monitored in a cohort of traffic police (n = 53) at six locations in Kathmandu Valley, Nepal during dry and rainy seasons in 2014.
Results: Mean on-road exposure levels of PM2.5 and BC ranged from 34 to 193 μg/m(3) and 12 to 28 μgC/m(3), respectively, and were associated with an acute decline in lung function. Use of N95 mask had clear benefits reducing the lung function decreases after occupational exposures when masks were worn for just half of a workweek.
Conclusions: Exposure of high levels of PM2.5 was associated with reduced lung function. Increased levels of BC exposure led to reduced lung function in non-smoking traffic officers with non-normal spirometry observations.