Story highlights Exposure to pollution particles is roughly equal in rural and urban areas

However, rural Indians are disproportionately affected by air pollution, researcher says

(CNN) Rural Indians, who make up about two-thirds of the country of 1.3 billion people, are disproportionately at risk of breathing polluted air, according to new research.

India's air pollution has been making headlines for years, with attention focused on Delhi, the capital, once named the most polluted city in the world by the World Health Organization.

Yet research published Thursday by an international team of scientists, including experts from the Indian Institute of Technology Bombay and the Health Effects Institute, estimates that 75% of air pollution-related deaths in India during 2015 came in its rural areas.

"Air pollution is a national, pan-India problem. It's not limited to urban centers and megacities, and it disproportionately affects rural Indians more than urban Indians," said Chandra Venkataraman, a professor at the Indian Institute of Technology Bombay, who was a member of the working group that conducted the study.

The study found that exposure to the smallest and most dangerous airborne pollution particles, known as PM2.5, was roughly equal across rural and urban India. Part of the reason for the higher proportion of deaths in rural areas, though, is that about two-thirds of the population still lives there rather than in cities, the scientists say.

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