The struggle faced by Rosamund Kissi-Debrah to get London’s severe air pollution listed on her nine-year-old daughter’s death certificate – a world-first if it goes through – is a grim reminder of the tragic consequences of worsening air quality in cities across the globe, and the threat it poses to the most vulnerable: children.

Respiratory infections are the most common chronic disease of children globally, and a leading cause of death in developing countries. The situation is exacerbated by air pollution in developing countries, home to many of the world’s most polluted cities.

Air pollution in north India, mainly New Delhi and the neighbouring states, is exacting a toll on the health of the residents, making global headlines, highlighting the severity and extent of the public health disaster in one of the world’s fastest growing economies.

A contributory factor to air pollution in north India is the harmful practice of crop residue burning – banned by the Indian government in 2015 yet prevalent in many parts of northern Indian states of Punjab, Haryana and Uttar Pradesh – when farmers burn the crop residue to clear fields before sowing a new crop.

In our study we found, for the first time, a link between crop residue burning and acute respiratory infection, and have estimated its economic and health costs.