Be that as it may, the 10-year-old study is a landmark—it is the most extensive and thorough study ever carried out on the correlation of Delhi’s air pollution with the health of its children. The only other major study of this nature one can think of—and one which is truly recent—is the 2015 study conducted by the HEAL Foundation, a non-government organisation. The researchers surveyed 2,000 schoolchildren nationwide, and their extrapolated conclusions: Nearly half of Delhi’s children suffer severe lung problems due to air pollution, were splashed across all newspapers and news channels on May 5. “Around 35% of school-going children in India suffer from poor lung health with Delhi topping the chart,” said NDTV .

What NDTV and others failed to report was that the HEAL Foundation survey was not only not a peer-reviewed study published in a scientific journal but, more worryingly, it was paid for by the global air-purifier company Blueair, which launched in India two weeks after the study was published.

NDTV, which incidentally is running a Clean Air, My Right campaign, has not brought to the attention of its readers and viewers this startling fact.

Returning to Harris’ magnum opus, the only other study he cites concerning Delhi’s air quality, or lack thereof, is a 2014 World Health Organisation (WHO) study that tabulates the prevalence of Suspended Particulate Matter PM10 and PM2.5 in 1,600 cities across the world during the period 2008-2013.

The WHO report mentions Delhi as having a mean PM10 value of 286 µg/m3 for 2010, and a mean PM2.5 value of 153 µg/m3 for 2013. Delhi’s air came out as one of the most polluted among all the cities surveyed. At the time this study was published, the government-run System of Air Quality Weather Forecasting and Research disputed the WHO findings, stating that PM values changed with seasons and became comparatively better than the values given for Beijing (121 and 56 for PM10 and PM2.5, respectively).

Interestingly, the PM2.5 value for Doha, Qatar, which has the highest GDP per capita among all the nations of the world, is 93 µg/m3 (year 2012). Abu Dhabi, the capital of the UAE had a PM10 value of 170 µg/m3. It should also be noted that in the 10-year-old study cited by Harris, and discussed in detail above, the 2002-2005 mean PM10 value for Delhi’s traffic intersection points was 250 µg/m3.

The PM10 and PM2.5 values for Delhi on the morning of June 03 are 120 µg/mand 71 µg/m3, respectively, less than half of WHO’s figures.

What’s going on? Has Delhi’s air turned healthier than what it was in 2010? Highly doubtful, considering the increase in vehicular traffic, the rampant burning of dry leaves despite high court guidelines, and the unbearable menace of street sweeping in the mornings. The PM2.5 range includes atmospheric, construction, cement, and settling dust, and dust it is that envelops millions of Delhi office goers and schoolchildren in the morning. Ravinder Raj, an 80-year-old man, has filed repeated public interest litigations to get the municipal corporation of Delhi to switch to sweeping the streets at night but to no avail. Just this simple solution, he says, can reduce the instances of respiratory diseases by 90%.

If Delhi is bad, it has company. “Half of the world’s urban population,” says the WHO study, “lives in cities that exceed by 2.5 times or more the recommended levels of fine particulate matter set out by the WHO Air Quality Guidelines and only around 12% of the total urban population lives in cities where the air quality complies with WHO levels.”

So, should Harris’ piece be ignored? Hardly. We as a nation collect everything else except data. The last National Family Health Survey (NFHS), the single-most important survey to judge our nation’s health, and one on the back of which hundreds of policies are drafted, the last NFHS was conducted in 2005, 10 years ago. Worsening air pollution is a reality, and what the departing Harris has done is given us a wake-up call. It is astonishing, and frankly unacceptable, that there exists no recent comprehensive and peer-reviewed scientific study on the effect of Delhi’s air pollution on its inhabitants, particularly the most vulnerable group, children.

The environment ministry’s website is silent on this. How can things improve if policy-makers have no up-to-date scientific study to base their decisions on, and are forced to rely on 10-year-old reports? Policy-making is not op-ed writing.

Harris moves to Washington this week along with his family, and if he believes the WHO findings his next important posting best not be in the world’s richest country, Qatar. But his last dispatch from Delhi might just be his most important, its PM2.5 value notwithstanding.

This piece was first published in Newslaundry. We welcome your comments at ideas.india@qz.com.

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