Heavy Metal Profiles of Medicinal Plants Found within the Vicinity of Quarry Site in Demsa, Adamawa State, Nigeria

Abstract

Heavy metals profile of ethanolic leaves extracts of some medicinal plants was carried out so as to ascertain the levels of Chromium (Cr), Cadmium (Cd), Lead (Pb), Manganese (Mn) and Nickel (Ni) in Anogeissus leiocarpus, Bauhinia reticulata, Prosopis oblonga, Sterculia tomentosa and Tamarindus indica, because leaves of these plants are used for treatment of some ailments by the people residing in that community were quarry factory was situated. The leaves of the plants were dried, grinded to powder and digested. The digests were analyzed for the trace metals using Atomic Absorption Spectrophotometer (AAS) model 210VGP and the result was interpreted using statistical analysis. The highest value for Manganese (Mn) was obtained from Anogeissus leiocarpus sample with 5.31 mg/l from the Quarry site, followed by Sterculia tomentosa with 1.6 mg/l, Tamarindus indica with 1.56 mg/l, Prosopis oblonga with 1.46 mg/l and least is Bauhinia reticulata with 1.22 mg/l. Chromium (Cr) has value of <0.04, Cadmium (Cd) with <0.01 and Nickel (Ni) having <0.05 in all the samples. The samples away from the Quarry site has 0.68 mg/l of Mn in Bauhinia reticulata while both Anogeissus leiocarpus and Tamarindus indica has values of 0.03 mg/l. Lead (Pb) was detected in only one of the control sample site with value of 0.08 mg/l in Bauhinia reticulata and in three plant samples from the Quarry site which include Anoggeissus leiocarpus with 0.06 mg/l and 0.07 mg/l for Bauhinia reticulata and 0.07 mg/l for Prosopis oblonga respectively. Other trace metals results obtained away from the quarry site include (Cr) with value of <0.04, (Cd) with <0.01 and (Ni) with <0.05 in all the samples. Some plants in the quarry site contain Mn and Pb above their threshold levels, therefore these plants are not recommended for consumption by animals to avoid bioaccumulation which will in further bring about health hazard.