Polyaromatic Hydrocarbons Levels and Bacterial Load on Soil after Consistent Disposal of Untreated Hairdressing Saloon Effluent in Lokoja, Kogi State, Nigeria.

This study estimated polyaromatic hydrocarbons levels and bacterial load on soil after thirty (30) days consistent disposal of untreated hairdressing saloon effluent in Lokoja, Kogi State, Nigeria using standard methods. After 30 days of pollution, the topsoil was collected from the height of 0-5cm, the midsoil (12-17cm) and the subsoil (25-30cm). A non-polluted soil sample was also collected which served as the control for this experiment. The total heterotrophic bacteria count was determined. Toxicity analysis was carried out to determine the effect of the effluent on soil bacteria. The soil samples were also analyzed for the presence of polyaromatic hydrocarbon using gas chromatography with mass spectrometry. The polyaromatic hydrocarbon (PAHs) detected in the test soil sample were 45.02ng/g Biphenyl, 28.23ng/g Benzo[a]pyrene, 12.05ng/g Anthracene, 23.00ng/g, and 5.07ng/g Phenanthrene. 2.01ng/g of Biphenyl was detected in the control garden soil. Bacteria counts from the contaminated soil range from 1.0 x102± 1.10 to 4.0 x 102 ± 0.11. The counts from the control soil sample range from 2.0 x103± 0.20 to 8.2 x103 ± 0.20. The control soil sample had a higher value compared to the test soil samples. Bacteria species isolated from these soil samples were: Serretia sp., Klebsiella sp., Escherichia coli, Pseudomonas sp., and Staphylococcus sp. with Pseudomonas sp. and Staphylococcus sp. showing increased percentage occurrence. The acute and chronic toxicity test showed a decline in the bacterial count, which could have occurred due to the presence of PAHs from Saloon effluent. It was observed that a constant release of PAHs into the soil poses serious threat to the survival of soil bacteria, and can alter the various beneficial roles these bacteria play in the soil ecosystem. [ABSTRACT FROM AUTHOR]