The vast majority of rural households in the developing world depend on biomass fuels for cooking and heating. Biomass fuels are formerly living organic matter such as wood, crop waste or animal dung. Handmade charcoal is an example of a semi-processed biomass fuel.

Rural Tanzanians predominantly cook over open wood fires in enclosed kitchens. House building materials vary from mud and thatch to concrete and metal, but all hold cooking smoke in the house, creating a polluted, hazardous environment. Many regions are prohibitively cold or seasonally too wet to allow outdoor cooking. Even in warm, dry regions, outdoor cooking exposes food to pests and predators and thus indoor kitchens are favored.

Women - responsible for cooking, and young children – swaddled to a mothers back, are exposed to the highest levels of smoke pollution. Indoor cooking smoke contains particulate matter, carbon monoxide, polycyclic aromatic hydrocarbons and other noxious chemicals. Repeated exposure to smoke from traditional cooking practices in impoverished countries is responsible 1.6 million premature deaths annually, predominantly in women and young children. Further, acute lower respiratory infections, strongly associated with exposure to biomass smoke, are the number one killer of children under the age of five.

For more information on the health risks of cooking smoke exposure see: World Health Organization