Air pollution is commonly measured with immobile detectors attached to buildings. Measured pollution levels do not necessarily relate to the impact of air pollution as experienced on the street. Josh Apte and colleagues addressed the question of air pollution as experienced by commuters by measuring concentration of pollutants in a transportation micro-environment, i.e. in a moving auto-rickshaw in New Delhi.
New Delhi, as other cities in rapidly developing countries, is plagued by chronic congestion and air pollution, producing massive social costs for its inhabitants.
The main results of this study are three-fold. First, measured exposure concentrations are higher in New Delhi than measured before in other megacities. Second, high short-duration peak concentrations, integrated over time of exposure, are a main culprit of the overall high exposure. Third, the total exposure of one commute in an auto-rickshaw approximately corresponds to the total daily exposure experienced by city inhabitants in rich countries.
While New Delhi switched its public bus fleet from diesel to clean natural gas, this seemed to not have been sufficient to reduce air pollution to acceptable levels. In fact, on-street air pollution is likely to even worsen because of increased vehicle ownership an on-going trend to diesel LDV.
The high costs and impacts of air pollution seem to warrant much tighter regulation of vehicle emissions also in developing countries. In addition, enforced parking management and a more comprehensive bus rapid transit system with dedicated bus lanes may not only benefit air quality but increase also transport efficiency.
Read also this blog here, and watch the video tracking on-street exposure.