Polycyclic aromatic hydrocarbon burden in ambient air in selected Niger Delta communities in Nigeria

Abstract

The Niger Delta area in Nigeria has major oil producing and refining centers that characterized enormous industrial activities, especially in the petroleum sector. These industrial processes release different kinds of atmospheric pollutants, of which there is paucity of information on their levels and health implications. The objective of this study was to determine the ambient levels of polycyclic aromatic hydrocarbons (PAHs) in communities of a local government area (Eleme) where oil wells, petrochemical installations, a refinery, and a fertilizer complex are located. Respirable particulate matter (PM) in air were collected using Anderson high-volume sampler with PM with aerodynamic diameter ≥10 μm (PM10) inlet for collecting filterable, particle-bound PAHs according to standard methods. PAHs were analyzed following standard methods for the 16 World Health Organization (WHO) prioritized components. The results were compared against the levels in another local government area (Ahoada East) with low industrial presence. The average total PAH concentration in Eleme of 9.2 µg/m3 was among the highest in the world; by contrast, the average concentration in Ahoada East was only 0.17 ng/m3. The most prominent PAHs at Eleme were those known to be carcinogenic and included benzo(a)pyrene (1.6 × 104 ng/m3 at bubu), benzo(k)fluoranthene (2.4 × 104 ng/m3 at Akpajo where a petrochemical is located), pyrene (3.1 × 103 ng/m3 at Ogale), and indeno(1,2,3-cd)pyrene (9.1 × 103 ng/m3 at Akpajo). Data from this study emphasize the need for a comprehensive source apportionment study and an assessment of the health effects of oil production on local communities of Nigeria where no such information currently exists. Implications: This investigation reveals that communities adjoining industrial locations in Nigeria's Delta area are more exposed to higher concentrations of pollutants. This predisposes affected communities to environmentally induced health problems. The scenario requires a review of policy that would compel industrial facilities in the area to improve their pollution control regimes. This should be supported by stringent environmental monitoring by regulatory authorities. Also there is the need for in-depth epidemiological and toxicological studies in order to establish causality between the environmental exposure factors and emerging health problems. The outcome of such studies would be critical for instituting intervention programs in the area.