Determination of toxic metals in salt deposits in Bormanda, Nigeria

Abstract

Heavy metals which may co-exist with soil salt, when present above their threshold levels could be hazardous to the body system. Common salt samples extracted from soil samples from Bormanda and Karim Lamido Local Government Areas in Taraba State, Nigeria, were digested in aqua-regia and analysed for Lead, Cadmium, Chromium, Arsenic and Nickel using Atomic Absorption Spectrophotometry. The mean concentrations (mg/kg) of Lead (0.470±0.005) and Cadmium (0.040±0.001) were higher than the threshold levels recommended by World Health Organisation. However, the level of Nickel (0.140±0.003 mg/kg) was within the threshold limit. Chromium and Arsenic were not detected in any salt sample. The results revealed the occurrence of some toxic metals in association with the soil salt deposits. Works on selective removal of the heavy metals is therefore suggested to isolate the toxic metals from the soil salt samples.