Carcinogenic and non-carcinogenic risk assessment of consuming metal-laden wild mushrooms in Nigeria: Analyses from field based and systematic review studies

This study investigated the potential health risk associated with the consumption of metal-laden mushrooms in Nigeria. Concentrations of Pb, Cd, Cr, Cu, Ni, Zn and Al in wild mushrooms collected from the Nigerian environment were measured using atomic absorption spectrometer. Also, systematic analysis of articles on metal accumulation in mushrooms from Nigeria were obtained from scientific databases. Using hazard model indices, the metal concentration in mushrooms were evaluated for their potential carcinogenic and non-carcinogenic health risk when consumed by adults and children. Zn and Cd, respectively, had the highest and lowest mean concentrations (mg kg-1) in the analysed mushrooms from the field study, while Fe and Co, respectively, had the highest and lowest mean concentrations (mg kg-1) in the systematically reviewed articles. In the field study, the percentage distribution of THQ of the heavy metals greater than 1 was 0% and 42.85% for adults and children respectively. While for the systematic study, 30% and 50% of the heavy metals for adults and children respectively exceeded the limit of 1. The hazard indices obtained from both the systematic and field studies for both age groups were all >1, indicating significant health risk. The findings from both the systematic and field studies revealed that consuming metal-laden mushrooms by adults and children increases the carcinogenic risk to Cd, Cr, and Ni since they exceeded the acceptable limit of 1E-04 stated by USEPA guideline. Based on the findings from the systematic and field studies, it suggests that consuming mushrooms collected from metal polluted substrates increases carcinogenic and non-carcinogenic health risk among Nigerians.