Atmospheric environment problems in Nigeria—An overview

Abstract

The air pollution sources in Nigeria are discussed. Particulate matter constitutes the major atmospheric pollution problem. Both anthropogenic and non-anthropogenic sources of paniculate matter were found to be important. The Harmattan dust haze constitutes the largest anthropogenic source of particulate matter. Severe visibility reduction and increased incidence of respiratory and chest congestion complaints are recorded during the Harmattan season. Dust remobilization resulting from vehicular traffic on unpaved as well as on unswept paved roads and from fugitive emissions from open surfaces and biomass burning are the major non-anthropogenic sources of particulate matter. Industries generate and emit particulate as well as gaseous pollutants which have manifested significant negative impact at local levels. Combustion-derived pollution was seen to be increasing. The annual atmospheric particle loading for the country was estimated as 2.75 × 10 9 kg with the following source contributions: bush burning (31.7%), fugitive dust from roads (29.1%), fuel wood burning (21.3%), Harmattan dust (13.8%), solid waste incineration (2.1%), stationary sources (1.6%), automobile exhaust lead (0.2%) and gas flares (0.1%). Very little data exist on the ambient air quality of Nigerian cities. The few synoptic data available indicate ambient concentrations of CO and SO 2 exceeding WHO short-term limits for those gases. The results of lead level measurements in biotic species and in road surface dusts at several locations were found to be high. Important meteorological peculiarities of the atmosphere over Nigerian urban and industrial cities were considered. The air pollution potentials of these cities were then discussed.