The US-based Health Effect Institute’s report published in February 2017 claims that in 2015, half of the air pollution-related deaths in the world occurred in India and China. In India, 10,90,400 died due to toxic air.
The World Health Organisation (WHO) had also stated that out of 20 most polluted cities in the world, 11 are in Punjab, Uttarakhand and Uttar Pradesh. According to a Greenpeace study, Delhi is the most polluted city in India. Data collected in March 2017 shows that Mumbai’s air was three times worse than Delhi’s.
The HEI’s report says that exposure to PM2.5, the leading environmental risk factor for death, accounts for about 4.2 million deaths, ranks fifth worldwide among all risks, including smoking, diet, and high blood pressure.
While hundreds of different chemical compounds can be measured in air, governments typically measure only a small subset of gases and particles as indicators of the different types of air pollution. Fine particulate matter (PM2.5) and ozone are the two indicators used to quantify exposure to air pollution in the Global Burden of Disease Study (GBD), on which the Health Effect Institute’s report is based.
The GBD is a comprehensive regional and global research programme of disease burden that assesses mortality and disability from major diseases, injuries, and risk factors.
PM2.5 is the most consistent and robust predictor of mortality in studies of long-term exposure to air pollution. Ozone, a gas produced via atmospheric reactions of precursor emissions, is associated with respiratory disease independent of exposure to PM2.5.
According to the report, among the 10 most populous countries and the EU, Bangladesh and India now have the highest exposures to PM2.5, having experienced the steepest increases since 2010.
Air pollution remains one of the major risk factors worldwide and of particular concern in developing countries. In Delhi, the ambient air pollution levels last winter were extreme enough that it became impossible to ignore it. Even the government was forced to acknowledge the severity of the issue.
But given the wide-ranging scale and scope of this issue, there are no easy ways forward. In fact, we don’t even fully understand many dimensions of the issue. Let us start at the top.
Data from the Institute for Health Metrics and Evaluation (IHME) and the World Bank World Development Indicators Database, which compares the deaths attributable to air pollution in India, China and the world in 1990 to those in 2015, casts light on various issues.
Chief among them is that overall 4.2 million deaths are attributable to ambient air pollution (AAP) and 2.9 million deaths to household air pollution (HAP) worldwide in 2015. For India, the corresponding numbers are 1.1 million (for AAP) and 1 million (for HAP) respectively.
Notably, much of the global focus is on AAP. UNICEF, for example, released a major study in late 2016 titled ‘Clear the air for children’, highlighting the harm to children from breathing polluted air, focusing mainly on AAP.
The Institute for Health Metrics and Evaluation and Health Effects Institute recently released the State of the Global Air 2017 that reiterates the role of air pollution as a major global risk factor for disease, but again, with the main focus on AAP. This may well be because AAP, unlike HAP, is a factor common even to high-income countries.
The data also shows that there has been some progress in addressing the HAP issue, with the global mortality rates having dropped by about 40 per cent. In India, while the mortality rates attributable to HAP have reduced by about 30 per cent, we remain far above the world average and even above China.
So, for India, the basic point stands that air pollution is a major health issue, that HAP and AAP are both almost equally important in terms of their relative health impacts, and that we have made a little bit more progress in addressing HAP than AAP.
What is the way forward?
As the report of the Steering Committee on Air Pollution and Health of the Ministry of Health and Family Welfare noted, what matters most for health impacts is exposure to air pollution and therefore the most effective and efficient strategy would be one that addresses emissions that cause the greatest exposure.
On the HAP front, where the dominant source is polluting household cooking energy (i.e., traditional chulhas or stoves burning biomass, dung, cola, etc.), we have made some good headway with the government’s programme promoting access to LPG among poor households through the ‘Give it Up’ initiative that effectively transferred LPG subsidies from well-off households to poorer ones, and then the Pradhan Mantri Ujjwala Yojana (PMUY), launched in April 2016, which aims to provide five crore LPG connections to BPL families within the next three years.
According to the Ministry of Petroleum and Natural Gas over one crore well-off households "gave it up" and over 2.1 crore households have been provided LPG connections under the PMUY. At the same time, the other major route to clean household cooking - deployment of induction stoves - may also be worth considering, especially if one is able to leverage the expansion of solar photovoltaic in rural and remote areas.
On the AAP front, the situation is more complicated. There are a multitude of sources — vehicles, power plants, industry, crop and other biomass burning, road dust, etc. — with the contribution varying across regions. Since most of the exposure is in urban areas, from a health perspective, there is much focus on air pollution in cities.
We do not have the kind of data and studies to build a robust picture of emissions and exposures across our cities. But we can still prioritise emission reductions, as outlined in the Ministry of Health and Family Welfare report and the recent EPCA (Environment Pollution Control Authority) draft comprehensive action plan for air pollution control in the National Capital Region.
We can draw upon the experiences of other countries in, for example, managing transport emissions through steps ranging from promotion of mass transport, congestion charges, and cleaner vehicles. Other cases, such as managing the burning of crop waste in agricultural areas and burning of biomass and other material in cities, may require policy instruments that are designed for the local context. Again, there is no silver bullet but a variety of steps will be needed to address the issue.
Many relevant policies already exist on paper - such as those intended to control crop burning - but are not implemented. Other experiments such as plying vehicles on ‘odd-even’ days have had only limited success. But all in all, we are a long way from effectively addressing the AAP problem.
Making headway on this issue, especially the AAP aspects, will require progress on many fronts, including understanding the local manifestations of air pollution and its causes, impacts, and the effectiveness of various policy instruments. But more than anything, it will require political commitment, which in turn likely will need to be driven by sustained and strong public engagement and pressure. If we all don’t rise to the challenge, it is unlikely that the decision-makers will. But that’s generally the case, isn’t it?
According to the State of Global Air 2017 report, as many as 2.54 lakh deaths occurred in 2015 on account of exposure to ozone and its impact on chronic lung disease.
India+ accounts for the highest number of premature deaths due to ozone pollution, its toll 13 times higher than Bangladesh’s, and 21 times higher than Pakistan’s.
Long-term and acute exposure to air pollution can lead to cerebrovascular disease, asthma, various adverse birth outcomes, diabetes, lung cancer and neurological disorders.
From cooking residue to paints, varnishes and fungal spores, the air we breathe indoors is often more polluted than that outside.
(Ambuj Sagar is Professor Policy, Humanities & Social Sciences at IIT-Delhi)
