Polycyclic aromatic hydrocarbons in harvested rainwater in Warri and Agbarho, Nigeria

Abstract

ABSTRACT. The aim of this research was to provide an overview of current knowledge, by assessing the possible contamination sources of harvested rainwater by polycyclic aromatic hydrocarbons (PAHs), its effects and possible human health risk assessment. Random sampling technique was used to collect eight rainwater samples from different roofing materials made from (asbestos, zinc, aluminium and thatch) in Warri and Agbarho (AGB). The samples were extracted using a liquid-liquid extraction (LLE) system according to the established procedures of United States Environmental Public Agency (USEPA). Under the optimized conditions, the ranges of extraction recoveries and solid-phase extraction (SPE) clean-up of the PAHs in the harvested rainwater were in the range of 71-90%. Gas chromatography-mass spectrometry (GC-MS) was used for the determination of the sixteen priority PAHs in the samples. The total concentration of PAHs for each of the roof types in Warri Refinery Petrochemical Company (WRPC) are: 0.036±0.012, 0.047±0.020, 0.045±0.018 and 0.0023±0.008 ppm for aluminium, zinc, asbestos and thatch roof, respectively. In addition, total concentration of PAHs for each of the roof types in AGB are: 0.046±0.020, 0.024±0.009, 0.023±0.008 and 0.021±0.007 ppm for aluminium, zinc, asbestos and thatch roof. The PAHs analysed exceeded the United States environmental protection agency (USEPA) standards of contamination.   KEY WORDS: AGB, GC-MS, Harvested Rainwater, LLE, PAHs,  WRPC Bull. Chem. Soc. Ethiop. 2022, 36(4), 779-789.                                                             DOI: https://dx.doi.org/10.4314/bcse.v36i4.5