Elemental Analysis of Medicinal Plants Used by Traditional Healers in Plateau State, North Central Nigeria

Medicinal plants occupy a central role in primary healthcare delivery for a significant proportion of rural populations in North Central Nigeria. However, the accumulation of toxic trace elements in these plants from contaminated soils or polluted environments poses potential health risks to users. This study determines the elemental composition, with emphasis on potentially toxic metals, in ten commonly used medicinal plants collected from traditional healers and market vendors in Plateau State. Plant samples were oven-dried, digested using a mixture of concentrated nitric and perchloric acids, and analysed for copper, lead, cadmium, zinc, manganese, iron, nickel, and chromium by flame atomic absorption spectrophotometry. Results show that all ten plants contain detectable levels of the analysed elements, with iron and zinc being the most abundant in most species. Lead and cadmium concentrations were below toxic thresholds in most samples, though two plant species collected from a site near a mining zone showed cadmium levels that warrant further scrutiny. Daily exposure estimates for patients using these plants in recommended therapeutic doses were calculated and compared with tolerable daily intakes. The findings support the need for quality control frameworks for traditional medicine practice in Nigeria, including systematic monitoring of metal content in widely traded medicinal plant materials. Keywords: medicinal plants, trace elements, Plateau State, traditional medicine, atomic absorption spectrophotometry