New Delhi: Air pollution woes have quadrupled for Delhi, as the state suffered the highest per-capita economic loss due to air pollution last year, a study in the peer-reviewed medical journal Lancet suggests.

For years, northern India -- especially New Delhi -- has been battling critical levels of air pollution, which have remained consistently in the hazardous mark, for many days at a stretch, during winters. This air pollution has already taken a big toll on the health of the citizens and rattled the government, forcing it to devise a new governance mechanism to address the menace of pollution in the capital.

The study said the economic loss due to lost output from premature deaths and morbidity from air pollution was 1.36 per cent of the GDP in India in 2019. In Delhi, the loss due to lost output from premature deaths and illness attributable to air pollution as a percentage of state GDP was 1.06 per cent.

Uttar Pradesh recorded the highest loss to GDP at 1.34 per cent followed by Punjab at 1.22 per cent. "Delhi had the highest per-capita economic loss due to air pollution, followed by Haryana in 2019, with 5.4 times variation across all states," said the findings.

According to the study, the economic loss per capita was highest in Delhi, which was to the tune of $62.0 followed by neighbouring Haryana at $53.8.

The study's findings suggested that 1.67 million deaths were attributable to air pollution in India in 2019, accounting for 17.8 per cent of the total deaths in the country.

The crude death rate per 100,000 population due to household air pollution decreased in India by 64.2 per cent from 1990 to 2019, due to reduced use of solid fuels, while that due to ambient particulate matter pollution increased by 115.3 per cent and that due to ambient ozone pollution increased by 139.2 per cent.

"The death rate due to household air pollution decreased by 64.2% (52.2-74.2) from 1990 to 2019, while that due to ambient particulate matter pollution increased by 115.3% (28.3-344.4) and that due to ambient ozone pollution increased by 139.2% (96.5-195.8)," said the study.

The authors of the study suggested that in 2019, the economic loss due to lost output from premature deaths attributable to ambient ozone pollution as a percentage of GDP in India was 0.05 per cent and varied 11.2 times across the states, ranging from 0.01 per cent in Nagaland to 0.12 per cent in Uttar Pradesh.

The economic loss due to lost output from premature deaths attributable to air pollution in India in 2019 was $28.8 billion and from morbidity attributable to air pollution was $8.0 billion.

"Of the total economic loss of $36.8 billion (27.4-47.7) attributable to air pollution in India in 2019, 36.6% was from lung diseases, which included COPD (21.1%), lower respiratory infections (14.2%), and lung cancer (1.2%), and the rest was from ischaemic heart disease (24.9%), stroke (14.1%), diabetes (8.4%), neonatal disorders (13.3%), and cataract (2.7%)," said the study.

Citing the US, the study said every dollar invested in the control of ambient air pollution since 1970 is estimated to have yielded an economic benefit of $30, based on the willingness-to-pay approach.

"There has been a substantial reduction in air pollution in the US over the past few decades along with significant economic growth, indicating that the successful implementation of air pollution control strategies could help in improving the health of the population, even when the economy is growing", said the study.

Prof Lalit Dandona, Director of the India State-Level Disease Burden Initiative, who is National Chair of Population Health at ICMR, Professor at PHFI, and senior author of this paper said, "Improved methods in this paper have led to a higher estimate of the impact of air pollution on health and disease in India than previously estimated.

"The economic impact of this health loss due to lost productivity is huge at 1.4% of the country's GDP in 2019, besides a roughly estimated expenditure of 0.4% of the GDP on treatment of air pollution related diseases. The health and economic impact of air pollution is highest in the less developed states of India, an inequity that should be addressed."