Health Implications of Bioaccumulation of PAHs in Fluted Pumpkin (Telfairia occidentalis) and Waterleaf (Talinum fruticosum) along the Imo River Watershed, Imo State, Nigeria

Abstract

The health implication of PAHs has been of great concern due to its contamination of the food chain. This study was carried out to identify the health challenges associated with the bioaccumulation of PAHs in Fluted Pumpkin (Telfairia occidentalis) and Waterleaf (Talinum fruticosum) along Imo River Watershed, Imo State, Nigeria. A total of 8 soil samples (0-30cm) were randomly collected from different activity areas on the watershed and analyzed for the presence of the 16 US-EPA priority PAHs in both soil and vegetable samples. The analysis of PAHs in the soil and vegetable samples were carried out in accordance with EPA 8270: (GC-MSD) and the results revealed that amongst the 16 US-EPA priority PAHs, eight of them were detected in the soil and vegetable samples. The total concentration of PAHs detected in the soil and vegetable samples were Naphthalene(0.146mg/kg), Acenaphthylene(0.010mg/kg), Acenaphthene(0.210mg/kg),Phenanthrene(0.021mg/kg),Anthracene(0.041mg/kg),Flouranthene(0.130mg/kg),Pyrene(0.020mg/kg),Benzo(b)fluoranthene(8.641mg/kg) and Naphthalene(0.090mg/kg),Acenaphthene(0.011mg/kg),Fluorene(0.010mg/kg),Phenanthrene(0.230mg/kg),Anthracene(0.190mg/kg),Flouranthene(0.010mg/kg),Benzo(b)fluoranthene(2.711mg/kg),I(1,2,3-cd)PY(0.540mg/kg) respectively. The decreasing order for individual PAHs concentration in the soil and vegetable samples within the study area were Benzo(b)Flouranthene>Acenaphthene>Naphthalene>Fluoranthene>Anthracene> Phenanthrene> Pyrene> Acenaphthelyne and Benzo(b) Flouranthene>I(1,2,3-cd)PY> Phenanthrene> Anthracene> Naphthalene>Acenaphthene> Fluorene>Fluoranthene respectively. For both soil and vegetables, total PAHs concentrations recorded in Obowo zone were observed to be higher than Okigwe zone. The result also revealed high values of PAHs in the edible vegetable samples collected around abattoirs and abandoned waste dump. It is therefore evident from this study that abattoirs and waste dumps have the potential to emit huge amount of PAHs to soil resource, which is taken up by edible vegetables leading to several health challenges when the vegetables are consumed. Different exposure to PAHs results in immune function suppression, cataracts, kidney and liver damage, skin inflammation, asthma, nausea, vomiting, eye irritation, diarrhea, confusion, lung and other cancers and probably death in chronic cases. There is need for public education on the consumption of vegetables grown in and around abattoirs and areas dominated by waste dumps.