摘要：Bafoussam is situated between latitude 5.42N - 5.60N and longitude 10.38E - 10.48E, is the capital and largest city in the Western Region of Cameroon. Increased urbanization and agricultural activities have potentials for trace metal pollution of groundwater. As such, trace metals evaluation of groundwater in Bafoussam is among the most important environmental issues related to contamination from natural and anthropogenic sources. This study investigated the trace metal content of groundwater sources; determined estimates of the health hazard and pollution risk indices; assessed the health hazard and level of risk to trace metal pollution in Bafoussam. Field measurement of physicochemical parameters from 206 Dug-wells and chemical analysis of 10 representative groundwater samples determined their trace metal content using Inductively Coupled Plasma Mass Spectroscopy ICP-MS and R-mode statistical analysis; Hierarchical Cluster Analysis (HCA) and Pearson’s correlation analysis (PCA) of the trace metal content with the physico-chemical parameters were carried out. Four pollution hazards were determined: the average daily dose ADD, carcinogenic risks CR, non-carcinogenic risk hazard quotient HQ and hazard index HI. Six pollution risks were determined: the Degree of contamination DC, Enrichment factor EF, Ecological risk factor Er, Ecological risk index RI, Pollution load index PLI, and geo-accumulation index Igeo. The relative abundance of trace metals levels in the sampled groundwater follows the decreasing order: Zn > Ba > Sr > Cu > Mn > Fe > Pb > Cr > Ni > Co > V > Cd > As > Li. HCA distinguishes trace metals into two clusters: cluster one is made up of 2 elements divided into two classes and cluster two is made up of 12 non soluble elements divided into three classes. The groundwater pollution hazard indices ADD, CR, HQ and HI are less than 1 in the categories of insignificant pollution health hazard and are below the acceptable guideline values. The pollution health risk indices DC, EF, Er, RI, PLI, and Igeo are all below the acceptable guideline values. The enrichment factor EF shows the sources of these metals are geogenic processes. Thus, from the health hazard indices and pollution risk indices, trace metal pollution of groundwater in Bafoussam is within the safe limits for drinking. However, due to an increasing level of environmental pollution that might be imposed by increasing human activity in this region, water sources might become a potential sink of trace metal contaminants; we recommend constant monitoring of groundwater.
