According to the World Health Organization (WHO), over three billion people all over the world (including India) use polluting fuels and devices—such as wood, coal, and dung in simple stoves—for their daily cooking. The subsequent household air pollution is the world's foremost environmental health risk. Globally, by far the most significant direct health risk is pollution caused by the partial combustion of fuel in low-efficiency stoves and lamps used for cooking, space heating, and lighting. There are other key contributors to household air pollution, which may include radon, emissions from construction and building materials, etc.

This month's cover story, 'Household (Indoor) Air Pollution: A Leading Environmental Health Risk' sheds light on the prominent causes of indoor air pollution (IAP) and its adverse impacts on human health. Cookstove emissions contain a wide range of harmful pollutants, carbon monoxide, nitrous oxide, and other harmful gases. Research studies indicate that air quality in Indian households, especially in the rural areas, is lethal due to use of wood or cow dung as cooking fuel coupled with poor ventilation. Exposure to household pollution increases the risk of pneumonia and acute lower respiratory tract infection amongst children and chronic obstructive pulmonary disease (COPD) and lung cancer amongst adults above 30 years of age. Women and children bear a large share of the associated health burden, and the adverse impacts from household air pollution are largely caused by energy poverty. Our cover story also discusses WHO's programme on household air pollution. To combat this substantial and growing burden of IAP, the WHO has developed a comprehensive programme to support developing countries. The WHO emphasizes the importance of planned research in the field of IAP. Fortunately, there has been a recent urgency in awareness and global determination to address this global health crisis.

The Energy and Resources Institute (TERI) has also been seized of this issue. Improved cookstoves (ICS) developed by TERI have the potential to deliver the benefits of improved household health and time savings. Benefits of reduced deforestation and local environmental degradation are also observed. Reduction in emissions of black carbon (soot) and carbon monoxide are also achieved. The improved cookstoves and chulhas help in improving the health of women and children by reducing exposure to IAP because there is 70 per cent reduction in smoke. ICS also reduce the cooking time to almost half and there is 50 per cent less consumption of fuel. So, it also reduces drudgery of women collecting fuelwood. Also, under the central government's 'Ujjwala' scheme, many Indian households now have access to clean cooking gas in the form of LPG cylinders. The key driver of such expansion has been the Indian government's determination to wean all homes off hazardous traditional cooking fuel, such as firewood and coal that cause household air pollution. The task to cover all households is huge, but significant efforts are now being made to achieve the objective.