The incidence and severity of air pollution in India is on the rise and urgent action is needed to halt its harmful health impacts, Ravindra Khaiwal writes.
The unprecedented air pollution levels recorded in Delhi during early November 2016 is alarming from both an environmental and public health perspective. The short and long-term exposure to harmful pollutants, with the level of PM2.5 recorded above 700 micrograms per cubic metre, may result in increased health risks. More must be done to ensure that public policy tackles this perilous pollution.
A recent Global Burden of Disease report highlights air pollution as one of the primary causes of deaths around the world. In India, air pollution was ranked as the fifth biggest cause of death after high blood pressure, indoor air pollution, tobacco smoking and poor nutrition. The World Health Organization (WHO) attributes seven million premature deaths globally to air pollution each year, the majority of which occur in Asia.
Analysis of the air quality data provided by the Central Pollution Control Board, an Indian statutory organisation, shows that it is not only the country’s megacities but also small and medium cities in India that exceed air quality norms. However, the focus of efforts from policymakers remains constrained to megacities, and specifically the country’s capital Delhi. The recent fog episode there, and the length of time it remained suspended over the city, brought the issue of pollution to the fore of media and public attention.
Delhi’s smog was blamed on Diwali firecrackers and stubble burning (where the straw remnants of rice / wheat and other grain crops are set alight) in neighbouring states. However, local emissions (such as from the vehicular load, industries, municipal solid waste burning, construction activities and non-exhaust emissions), the role of secondary pollutants, atmospheric reactivity, and meteorological parameters were not given due consideration in reaching this conclusion. Some steps, including imposing strict controls over stubble burning, closing thermal coal power plants and restricting diesel vehicles, were taken to curb the level of pollution. Primary schools were also closed down for few days to reduce small children’s exposure to harmful air pollutants.
Delhi: megacity, megatraffic, megapollution
By mid-November, the peak of particulate pollutants had passed in Delhi and with it went many of the concerns about air pollution. But out of sight should not mean out of mind, and what Delhi contended with isn’t just a problem affecting that city, but one that is a problem throughout the region. Unfortunately, although air pollution has no boundaries, actions to combat it remain focused on only a select few geographic locations.
Air pollution should be addressed in a comprehensive way, not focusing solely on megacities like Delhi but also on other cities to eliminate the causes of air pollution. This will not only require short and long-term planning but also systematic implementation. Further, greater awareness about air pollution will change public perceptions about the risks involved and help engage them as active stakeholders in managing the issue.
The Global Burden of Disease report and WHO data provide more than enough evidence on the incidence of poor air quality and its associated adverse health outcomes. We should not wait, therefore, for region-specific evidence before acting to reduce air pollution. Systematic source apportionment and emission inventories are required to yield detailed information about the sources of air pollution at specific locations. In turn, this will enable the planning of site-specific actions to reduce air pollution. The unplanned growth of cities and surrounding areas should be restricted and sustainable land-use planning should be implemented. For season specific sources of air pollutants, like stubble burning, farmers should be provided with incentives for the sustainable management of crop residues and at the same time green technologies should be promoted, which may significantly reduce the yield of waste crop residue or allow them to be utilised for waste-to-energy production.
There are also plenty of actions the government can take within cities, including promoting affordable public transport and greater provision for bicycles and pedestrians so that they can commute safely. The frequent burning of municipal solid waste and urban forestry waste also worsens air quality and public-private partnerships should be encouraged for efficient and effective waste management. Non-exhaust emissions reduction targets largely remain unattained, while European examples show that they can even exceed exhaust emissions. Hence, non-exhaust emissions also demand policy intervention. Indian economic growth is accelerating, with a multitude of construction activities going on in the cities and new highways being built. Emissions from construction and associated activities (brick kilns, stone crushing) should also be regulated.
Cities which promote a healthy environment and culture should be rewarded, while those that do not should be penalised. There is also need to educate the public and lift their awareness regarding the health risks of air pollution. This could be better documented with the help of more geographically-spread health risk studies. Policies should also be formulated to promote inter-sectoral co-ordination to act effectively on pollution control measures. Without such actions Delhi, along with India’s other cities and towns, will be doomed to remain under a cloud of toxic pollution while populations pay an increasingly high price on their health.