Runoffs from metal roof sheets (aged and New) in Otukpo LGA of Benue State,
to carter in Nigeria were analyzed to determine the level of heavy metals (Cd, Cu, Fe, Mn,
Ni, Pb, and Zn). All the runoff samples though varying in time and space contain heavy
metals concentrations. The results ranged from 0.003-0.009, µg/L, 0.165-0.291µg/L, 2.000-
2.987 µg/L, 0.091-0.199 µg/L, 0.101-0.187 µg/L, 0.011-0.035 µg/L and 2.733-3.892 µg/L
for Cd, Cu, Fe, Mn, Ni, Pb, and Zn in aged roof metal sheets, while in the new roof metal
sheets, the values are 0.002-0.008 µg/L, 0.071-0.191 µg/L, 1.010-1.994 µg/L, 0.073-0.995
µg/L, 0.076-0.111 µg/L, 0.012-0.036 µg/L, and 1.875-2.941 µg/L respectively. There were
significant difference (P<0.05) between run off from aged and new roof metal sheets. The
mean concentration of Fe, Cu, Ni and Zn of aged metal roof sheet were higher than the
mean concentration of new metal roof sheets. All the metals determined except Fe have
mean concentration lower than the recommended standard by WHO, CPA and FAO. The
variations in mean concentration between aged and new metal roof sheets in this study,
suggest anthropogenic inputs of these metals.