Clearing the air through the revised WHO guidelines
Earlier this week, the World Health Organization (WHO) announced new air quality guidelines that aid countries in defining air quality levels that protect public health.
The first revision of the guidelines since 2005, this review benefited from a wealth of new scientific evidence generated in the interim period across developed and developing countries. The data showed that severe impacts of particulate and gaseous pollutants on health occur even below levels previously considered acceptable by health scientists.
The result of these new guidelines is a reset in our understanding of what we consider safe and breathable air. Under the previous guidelines, over 90% of the global population was exposed to air that was considered unhealthy. With this revision, that number will only grow.
For India, this is a reminder of the folly of neglecting everyday air pollution and fixating on seasonal peaks in the national Capital. Tens of crore are being spent on ineffective boondoggles such as smog towers in Delhi, while other cities are receiving paltry budget allocations, reflecting the disconnect between intent and action. While the action plans submitted by the over 100 non-attainment cities under the National Clean Air Programme (NCAP) are a useful exercise, these are not legally binding. In addition, rural areas are neglected.
These new guidelines also come weeks after the government announced the formation of a panel under the environment ministry to review India’s National Ambient Air Quality Standards (NAAQS). Last revised in 2009, NAAQS, as they stand, are exceedingly lenient, given what we have learnt in the last decade about the impact of air pollution on premature death and illness in India and elsewhere. Compared to the updated WHO guidelines, NAAQS levels for PM2.5 alone will be eight-fold higher for 24-hour exposures, and four-fold higher for annual exposures. Indian lungs are no different from any others, so there is no scientific rationale for such a vast discrepancy.
There are key process lessons that can be learnt from the way the WHO and other agencies around the world, including the United States Environmental Protection Agency, conduct such reviews. At the centre is scientific evidence that is factored into decision-making and the role of key stakeholders at various stages in the process.
It has not been clear what scientific and epidemiological evidence was considered in decision-making for the previous revision of NAAQS in 2009. While this may have been due to a dearth of local data on the health effects of air pollution at the time, the last 12 years have yielded considerable evidence on the impact of air pollution exposure on cardiovascular and metabolic diseases.
Health impact studies, led in part by the Indian Council of Medical Research, have shown that ambient PM2.5 was responsible for almost a million premature deaths in India (2019). Clarity on how these significant scientific advances will be factored in must be an essential aspect of this process.
NAAQS revisions must also ensure that a diversity of voices are represented in deliberations, including from atmospheric science, public health, policy, law, and civil society. Greater inclusivity and transparency must be the hallmarks of this process.
WHO guidelines are a clear nudge from the health sector towards the deep decarbonisation of our economy necessary to achieve both climate and air pollution goals. However, as things stand, most — if not all — Indian cities struggle to meet NAAQS, let alone the updated WHO guidelines. Even the targeted 30% reduction from 2017 levels under NCAP, if met, will only provide marginal benefits in improving health.
To ensure air pollution no longer remains the single-largest risk factor for ill-health in India, we must commit to ambitious policies with time-bound targets. Placing public health at the centre of air quality management, coupled with a commitment to accountability and transparency in standard-setting, is the only way to ensure that the goals we set do not remain solely aspirational.
Bhargav Krishna and Santosh Harish are fellows at the Centre for Policy Research.The views expressed are personal