Emissions from vehicles, manufacturing, mining and industrial activities (including diesel-powered generators, copper smelters, ferro-alloy works, steel works, foundries, and cement and fertilizer plants) contain carbon, sulphur and nitrogen oxides, as well as hydrocarbons and particulates, causing localized smog.
Domestic combustion of 'biofuels' poses a risk for human health. Figures since 1980 show that the traditional use of biomass as a source of energy still accounts for over 70 per cent of total energy consumption in Eastern Africa (UNDP 2000) and consumption of biomass is predicted to increase over the next 20 years (FAO 2001b).
Figure 2a.6: Number of vehicles registered in Uganda in 1971-99
Demand for vehicular transport is on the increase in Eastern Africa and many of the vehicles presently on the road are old and inefficient. For example, as shown in Figure 2a.6, Uganda had around 44 500 vehicles on the road in 1971; by 1998 this number had climbed to over 182 400, a more or less four-fold increase in less than 30 years (MoWTC 2000). In Ethiopia, the capital, Addis Ababa, accounts for 41 per cent of all of the country's petrol consumption, indicating the concentration of vehicles and their emissions in Addis. Many of these vehicles are old and do not therefore have filtering systems (NESDA 2000).
Additional sources of air pollutants include both legal and illegal waste dumps. For example, in 1998, methane emissions from the municipal dump in Addis Ababa were estimated to be more than 9 Gg (1 Gg = 1 x 109 grams) (NESDA 2000).
Air quality standards for all major pollutants have now been established for most countries in Eastern Africa, but lack of resources renders enforcement less than optimum.
Addis Ababa has recently acquired a new pollutionmeasuring laboratory, costing
US$286 000, which will help to identify the type and amount of pollutants emitted
by factories in the city, assess the impacts on soil and water, and recommend
measures to prevent further environmental pollution (PanAfrican News Agency