Previous studies revealed high levels of metals in soils, drinking water, foodstuffs and food animals in
several communities in Tarkwa, Ghana. Therefore wild rats were trapped from 16 communities in
Tarkwa to estimate the environmental pollution state of metals; determine differences in sex in metal
accumulation; and assess the potential risks involved. Concentrations of arsenic (As), cadmium (Cd),
cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) were
measured in the livers and kidneys of wild rats; and livers accumulated higher levels of As than kidneys
but the reverse was for Cd and Pb. In both organs, As, Cd and Zn levels were higher in female than the
male rats. There was a strong positive correlation between body weight and Cd concentrations in livers
and kidneys of wild rats which reflects a mechanism of protection against the development of
osteopenia, although a biological effect remains a concern. Pb levels in the kidneys could cause intra
nuclear inclusion bodies and karyocytomegaly in the proximal tubular cells in 29% of wild rats in
Tarkwa and structural and functional kidney damage in 6%. Concentrations of As in kidneys of these
wild rats could cause glomerular swelling in 9% of rats. Principal component analysis of the results
showed that wild rats in Tarkwa were exposed to heavy metals and a metalloid through borehole
drinking water and soils.