Indoor Air Pollution Attributed to Solid Fuel Use for Heating and Cooking and Cancer Risk

The indoor environment is an important determinant of health as humans typically spend 90% of their time indoors. Indoor air pollution attributed to solid fuel combustion products from heating and cooking is a major public health challenge mostly throughout the developing world. Solid fuel consists of coal and various forms of biomass, such as wood, crops, and dung. In general, the most frequently utilized domestic fuel in China is coal. As for Africa and India, biomass fuel sources are typically used. The use of these fuels in poor and no-ventilation situations is worrisome as the attributed smoke has been associated with a variety of cancers, the most notable being lung cancer. Indoor emissions from household combustion of coal have been classified as a human carcinogen, whereas biomass combustion emissions have been classified as probably carcinogenic to humans. Further research is needed to elucidate the potential modification of the coal use and lung cancer association by genetic variation and the varying carcinogenic potential of coal subtypes. Additional studies evaluating the association between cancer risk and wood use are also warranted.