PT03 Persistent Organic Pollutants (POPs)
Exhibit Hall
8:00 AM - Tuesday
(PT021) Polycyclic Aromatic Hydrocarbons in surface waters and sediments of Niger Delta Rivers of Nigeria.
Ezemonye, L.1, Okeimen, F.2, Ukpebor, E.2, 1 Department of Zoology, University of Benin., Benin City, Edo State, Nigeria2 Department of Chemistry, University of Benin., Benin City, Edo State, Nigeria
ABSTRACT- This paper presents the first attempt to quantify the level and distribution pattern of polycyclic aromatic hydrocarbons (PAHs) in Nigerian Niger Delta rivers. Distribution of the PAHs was investigated in Surface water and Sediments from three Rivers in Western Niger Delta, ecozone (Ethiope, Benin & Warri Rivers) in 2003. Analysis of total PAHs and 16 PAH fractions were carried out using High Performance Gas Chromatography (HPGC) series 6890 using APHA 6630 method. The concentrations of PAHs are discussed in relation to matrices, seasonal and spatial variations. Null hypothesis of normality was rejected. Significant difference existed between the matrices. The concentrations were higher in sediment samples than in surface water and significantly different at P>0.05 df 54, t-value = 2.058. A seasonal variation of PAHs in surface water was observed with lowest concentrations occurring in March (summer) while higher concentrations occurred in April/May (wet season). According to spatial distribution, elevated concentrations of PAHs were found in surface water and sediments samples in coastal waters of Benin and Warri Rivers. Comparison of the distribution pattern of the PAHs fractions at different stations using the Principal Component Analysis (PCA) showed that PAHs fractions pattern differed in both stations and matrices. The five and six ring aromatics known as potent carcinogens were predominant in surface water and sediment samples. Concentration of total PAHs were compared with ecotoxicological benchmarks and regulatory guidelines to access potential concern for effects on aquatic and human health. Measured mean values in surface water and sediment samples exceeded the ecotoxicological benchmarks indicative of potential environmental hazards. This calls for environmental monitoring of this region of great ecological significance.
Key words: distribution, sediment, pahs, water