A United Nations Environmental Program (UNEP) study (2018), reveals that indoor air pollution may contribute to between 22 and 52% of India’s overall pollution levels. The report suggests that indoor emissions need to be reduced to improve air quality. According to the World Health Organization (WHO), 4 million people die every year from pneumonia and other diseases caused by indoor air pollution.

The report said, “A number of studies indicate that reducing emissions from household cooking and heating may be required to substantially improve ambient air quality in some parts of Asia and the Pacific.”

Environmental air pollution and indoor air pollution are linked to each other as people spend about 90% of their time indoors. According to the State of Global Air Report 2019, in India, an estimated 846 million people, about 60% of the total population, were exposed to indoor air pollution in 2017. Primary gases and substances are emitted directly from sources such as personal care products, cleaning or cooking products, etc. When secondary gases are produced by chemical reactions in the air. For example, cooking produces large amounts of VOCs (volatile organic compounds), CO2 (carbon dioxide), NOx (nitrogen oxides) and other particles. They create ozone with the help of sunlight.

According to the National Family Health Survey (2019-21) report, 56% of rural households are still using hardwood, 11% grass, crop residue, dung cake etc. for cooking. Urban households have better access to clean fuel, but cooking in poor ventilation worsens their condition.

Women are more exposed to indoor pollution as they are mainly involved in cooking in the country. The main reason behind pollution deaths in India is household burning of organic matter followed by coal burning and crop burning. Women, children and the elderly are more vulnerable to indoor pollution.

The main sources of fuel for heating and cooking are firewood, dung, crop residues and charcoal in different parts of the country. Fires emit pollutants including particulates, carbon monoxide, polycyclic organic compounds and formaldehyde.