DELHI – Nearly half of families in and around New Delhi have consulted a doctor for respiratory problems linked to the severe pollution ravaging the Indian capital, according to a new survey.

Around 81 percent of people who responded to a questionnaire by survey institute LocalCircles said one or more members of their family suffered from an illness linked to exposure to toxic air.

Four out of ten households consulted a doctor, in the most serious cases going directly to the hospital.

Responding to a separate question, half of participants said that in the past three weeks they had purchased medications or devices, including cough syrup, inhalers and, in some cases, antibiotics.

The survey results underscore the risks that environmental degradation poses to Prime Minister Narendra Modi’s administration as it seeks to grow the economy of the world’s most populous country.

Prolonged exposure to airborne toxins, which authorities have historically failed to address, contributes to about a million deaths a year in the country.

“This is a public health issue and we will take this investigation to the government today,” said LocalCircles founder Sachin Taparia, adding that he would approach national and local authorities.

A spokesperson for the Ministry of Health and Family Welfare was not immediately available for comment.

The LocalCircles survey, which reached around 11,000 people for each of the two questions, provides a rare snapshot of the immediate health impacts of the capital’s poor air quality.

Delhi remains one of the most polluted cities on the planet all year round, but the situation gets worse during the colder months.

This year, pollution levels in the capital fell into the “very unhealthy” or “dangerous” category for 25 days in the last month alone, according to Swiss monitor IQAir. BLOOMBERG