Effect of fuelwood use on human health

3 Source: Ghana Energy Commission, 2013

1.2 The effect of fuelwood production on the environment

Fuelwood or firewood is the cheapest form of wood fuel in Africa because its production usually requires no complex expensive equipment and often procured at no greater cost than labour for collecting and processing Arnold et al., 2003. For this reason fuelwood is extensively exploited for income and for subsistence in both rural and urban areas across the region. Thus, fuelwood production across Africa has generally been criticized as a driver of deforestation Parrotta et al., 2015. The burning of wood for heat for household and industrial purposes also contributes to environmental decline. The environmental impact of using wood as a fuel depends on how it is burnt. Higher temperatures result in more complete combustion and less noxious gases as a result of pyrolysis. Some may regard the burning of wood from a sustainable source as carbon neutral. However, a tree, over the course of its lifetime, absorbs as much carbon or carbon dioxide as it releases when burnt. Wikipedia, 2015. Burning wood creates numerous by-products, some of which may be useful heat and steam, and others that are undesirable, irritating or dangerous. One by-product of wood burning is wood ash, which in moderate amounts is a fertilizer mainly potash, contributing minerals, but is strongly alkaline as it contains potassium hydroxide lye. Wood ash is also used to manufacture soap. Some irritating and potentially dangerous by-products from the partial burning of wood include smoke containing water vapour, carbon dioxide and other chemicals and aerosol particulates, including caustic alkali flyash. A major component of wood smoke is fine particles that may account for a large portion of particulate air pollution in some regions. During cooler months, wood heating accounts for as much as 60 of fine particles in air in Melbourne, Australia Wikipedia, 2015. It is reported that slow combustion stoves increase efficiency of wood heaters burning logs, but also increase particulate production. Low pollution from slow combustion stoves are a current area of research. An alternative approach is to use pyrolysis to produce several useful biochemical by-products, and clean burning charcoal, or to burn fuel extremely quickly inside a large thermal mass, such as a masonry heater. This has the effect of allowing the fuel to burn completely without producing particulates while maintaining the efficiency of the system. In some of the most efficient burners, the temperature of the smoke is raised to a much higher temperature where the smoke will itself burn e.g. 609 °C for igniting carbon monoxide gas. This may result in significant reduction of smoke hazards while also providing additional heat from the process. By using a catalytic converter, the temperature for obtaining cleaner smoke can be reduced. Some U.S. jurisdictions prohibit sale or installation of stoves that do not incorporate catalytic converters Wikipedia, 2015.

1.3 Effect of fuelwood use on human health

Depending on population density, topography, climatic conditions and combustion equipment used, wood heating may substantially contribute to air pollution, particularly particulates. The conditions in which wood is burnt will greatly influence the content of the emission. Particulate air pollution can contribute to human health problems and increased hospital admissions for asthma heart diseases. The technique of compressing wood pulp into pellets or artificial logs can reduce emissions. The combustion is cleaner, and the increased wood density and reduced water content can eliminate some of the harmful substances. Wood combustion products can include toxic and carcinogenic substances. Generally, the 4 heartwood of a tree contains the highest amounts of toxic substances, but precautions should be taken if one is burning wood of an unknown nature, since some trees wood smoke can be highly toxic Wikipedia, 2015. Generally, men and women have different demands on energy due to the existing socio- cultural and traditional roles. Women do most of the cooking. They are also heavily involved in fuelwood collection. Traditional use of firewood has negative effects on women’s health such as respiratory diseases, eye irritation, etc. Gender division of labour and environmental degrada tion are increasing women’s time burdens Neequaye Tetteh, 1985. A report in the Ghanaian Daily Guide news paper indicates possible inhalation of poisonous substances into the respiratory tracts of women who use charcoal in enclosures for cooking Daily Guide, 2015.  Studies conducted by SNV Ghana indicates that, some of the key traditionals wood species used for smoking fish in Ghana have various levels of Policyclic Aromatic Hydrocarbons PAH. Using five wood species, neem, red mangroves, white mangroves, rubber and bamboo to smoke sardinella on common stove Chorkor smoker, the PAH levels measured on the fish far exceeded the EU PAH standard for safe consumption Figure 1b. Higher levels of PAH on smoked fish has potential health hazards. This is because the high PAH has carcinogenic potential causing breast cancer, cervical cancer, liver, prostate, pancreas and cancer of hemapoietic organs.  Figure 2 PAH levels on sardinella from five fuelwood species

1.4 Fuelwood and development policies