India's crisis: death by foul air

When Sundeep Salvi and his colleagues knocked on the doors of villagers near Pune more than a decade ago, they didn’t have much inkling about what would they stumble upon. The scientists from Chest Research Foundation were looking for an answer to a medical puzzle: why a large number of non-smoking Indian women landed up in a doctor’s clinic with some sort of respiratory trouble – chronic obstructive pulmonary disease (COPD) in medical terms?

The research by Salvi and his colleagues was possibly the first large-scale scientific study to accurately point out why the air inside most Indian households is toxic. The houses have poorly ventilated kitchens where, for years, solid fuel is used for cooking, exposing the women to a lethal cocktail of poisonous gases, dust and soot.

While the causes were known, there was barely any remedy for years. Notwithstanding some decline in recent years, household air pollution continues to cause nearly 50% of air pollution-related deaths, as reported by a comprehensive study published in the journal Lancet, based on the Global Burden of Disease datasets.

The air outside the house is no better. With poorly regulated pollution control infrastructure, rampant construction activity, little landscaping and shoddy public transport, ambient air pollution, too, is on the rise, and so are the number of deaths caused by it.

Out of the estimated 25 lakh deaths due to pollution in India in 2015 – the highest in the world - air pollution accounts for more than 18 lakh deaths while water pollution killed another 6.46 lakh Indians that year.

India has one of the world’s worst average ambient pollution, with 25-50% of ambient air pollution coming from the use of solid fuels in two-thirds of Indian households.

How serious is the medical situation? A few years ago, Salvi and his collaborators asked 7,400 doctors from 880 cities to document their patient profile for a single day. The doctors recorded the symptoms and medical conditions of the patients they see in a day. It created a database of 2,04,912 patients. “More than half of all patients presented with respiratory symptoms across all age groups and regions of India,” the researchers reported in a 2015 paper in the Lancet.

Air pollution is grouped into two categories — household air pollution and ambient air pollution, though there are overlaps. Also, air pollution disperses globally, depending on the winds.

“Nearly 75% risk of COPD comes from the use of Chulha (solid fuel-burning cooking stove) in the houses. Another 20% risk comes from road dust,” Anurag Agarwal, director of the CSIR’s Institute for Genomics and Integrative Biology, and one of Salvi’s collaborators, told DH.

Besides respiratory issues, the dust in the air (Particulate Matter (PM)-2.5 and PM-10) can trigger many other diseases ranging from heart diseases and lung cancer to low birth weight in babies.

Though spoken about little, water pollution, too, kills in lakhs. The two major causes of water pollution are unsafe sanitation and filthy source, that together account for 6.46 lakh deaths.

Some of the worst biological and chemical pollution of drinking water is seen in rapidly urbanising and industrialising lower to middle income countries like India, where local waterways and groundwater are heavily polluted and serious health conditions are widely reported, but no alternative water sources exist. The principal diseases linked to water pollution are acute and chronic gastrointestinal diseases, most importantly diarrhoeal diseases (70% of deaths attributed to water pollution), typhoid fever (8%), paratyphoid fever (20%), and lower respiratory tract infections (2%). Most deaths caused by unsafe sanitation and unsafe water sources occur in children younger than five years of age.

In addition to air and water, there are occupational pollution hazards, like exposure to lead, passive smoking (accounting for 1,68,141 annual deaths in India) and contamination of soil by pesticides and other chemicals (95,843).

Taken together, pollution accounts for 24.45% deaths in India, among the highest in the world. In absolute terms, the death count is 25,15,518.

The maximum number of pollution-related deaths occur in Asian countries like China, Bangladesh, Nepal, Bhutan and North Korea. Globally, pollution kills 90 lakh people, out of which 65 lakh are done to death by foul air alone. Among the world’s 10 most populous countries in 2015, the largest increases in numbers of pollution-related deaths were seen in India and Bangladesh.

In 2015, more than 99% of deaths due to household air pollution and approximately 89% of deaths due to ambient air pollution occurred in low-income and middle-income countries. Several cities in India and China record average annual concentrations of PM-2.5 pollution of greater than 100 micrograms per cubic metre (safe level 60), and more than 50% of global deaths due to ambient air pollution in 2015 occurred in India and China.

In 2006, economist Todd Stern showed to the world how climate change is an impending economic crisis and not merely an environmental challenge. The Lancet report now points out that welfare losses due to deaths and disease from pollution equate to $4.6 trillion each year (equivalent to 6.2% of global economic output).

Proportionately, low-income countries pay 8.3% of their gross national income to pollution-related death and disease, while high-income countries pay 4.5%. The welfare loss for India is $270 billion (13% of 2015 GDP) whereas for China it is ($1.3 trillion; 12% of GDP).

It is evident that India’s pollution control needs to improve by leaps and bounds. But a question is often asked -- whether the pollution-control methods that worked in the US and Europe would also work in India, whose geography and economics are completely different?

“The issues in controlling pollution in India are similar to the US and Europe in terms of controlling pollution from stationary sources (power plants, industry) and motor vehicles. However, burning of biomass contributes 25% of PM-2.5 in India. Re-suspended road dust and agricultural burning are more important sources of PM-2.5 in India than in the US and Europe,” Maureen Cropper from the University of Maryland and one of the co-authors of the Lancet paper told DH, highlighting the areas where actions are needed.

There is some action to control pollution in the national capital region because of the pressure exerted by a Supreme Court appointed committee. There is barely any action in other parts of the country.

Meanwhile, the Union Environment Ministry, rather than acting on what’s a worsening crisis, has moved the Supreme Court challenging the studies that red-flag India’s high pollution load and its links to deaths.