In poor developing-country households, wood, charcoal and other solid fuels (mainly agricultural residues and coal) are often burned in open fires or poorly functioning stoves.
Incomplete combustion leads to the release of small particles and other constituents that have been shown to be damaging to human health in the household environment. Too little is known, however, to distinguish any differences in health effects of smoke from different kinds of biomass.
The emission of PM2.5, PM10, formaldehyde, and acetaldehyde were 5-10 times those of the second highest charcoal. The results suggest that the adverse effects of the large amounts of air pollutants generated during indoor charcoal combustion on health and indoor air quality must not be ignored
It is clear also to say that ,A large part of the world’s population uses fuelwood for household cooking and space heating, mostly in developing countries.
Energy from traditional biomass fuel is thought to account for nearly one-tenth of all human energy demand today (more than hydro and nuclear power together), and wood-based fuels probably make up some two-thirds of household use.
Given that levels of household solid fuel use are expected to remain high, efforts to improve household air quality are concentrated on improving stove efficiency and venting the smoke away from the home.
Wood and other biomass fuels can be burned cleanly with the right technology and thus can have a long-term role in sustainable development where they are renewably harvested. Thus programmes for the modernization of woodfuel use for household and cottage industries in the poorest areas of developing countries should be part of the development agenda.