Commuter exposure to air pollution in Newcastle, U.K., and Mumbai, India

The results of a study on commuter exposure to carbon monoxide (CO) and PM₁₀ during transit in the several commonly popular modes of transport in Mumbai, India, and Newcastle, U.K., are presented in this paper. In Mumbai, real-time exposure concentrations were measured while commuting along a route by bus, train, air-conditioned taxi, and a non-air-conditioned private car. In Newcastle, real-time exposure concentrations were measured while traveling by electric vehicle, public bus, and bicycle along a route. Average heart rate while commuting was monitored and subsequently simulated in a submaximal exercise test to give minute ventilation (VE) associated with each transport mode. The study in Mumbai has indicated that commuters traveling on buses and private non-air-conditioned cars are exposed to very high levels of air pollution compared with the train commuters. In Newcastle, electric vehicles and bicycles displayed the lowest exposure concentrations relative to buses. Higher exposure concentrations were observed for all travel modes in Mumbai as compared with Newcastle. When the inhaled amount and the lung deposition of pollutants are considered, cyclists are exposed to a higher amount of exposure dose in Newcastle because of the considerable increase in VE induced by the physical exertion of cycling. Thus, inhaled quantity and pollutant dosage give a better indication of the possible health risks and should be considered in future studies and in designing the cycle routes in cities.