An Assessment of Heavy Metal Analysis on the Medicinal Plant Stylochaeton hypogaeus Used for the Treatment of Prostate Diseases in Casamance (Senegal): Implication for Human Health

Abstract

Monitoring the presence of minerals in medicinal plants has become a health emergency due to the widespread consumption of herbal products and the risk of long-term bioaccumulation of heavy metals. This study aimed to determine the amount of heavy metals in the medicinal plant Stylochaeton hypogaeus, used in Casamance (Senegal) to treat hemorrhoid and prostate diseases. Minerals concentrations in roots, stems and leaves of Stylochaeton hypogaeus were in the range of 401.1 to 3505.4 mg/kg for sodium, 9370.1 to 63359.9 mg/kg for potassium, 1824.1 to 6074.3 mg/kg for magnesium, 2136.8 to 11530.0 mg/kg for calcium, 0.1 to 4.6 mg/kg for chromium, 96.8 to 345.3 mg/kg for iron, 0.00 mg/kg for nickel, 3.5 to 3.7 mg/kg for copper, 19.6 to 38.9 mg/kg for zinc, 0.2 to 0.3 mg/kg for cadmium and 1.0 to 2.4 mg/kg for lead. The levels of toxic heavy metal such as Cr, Fe, Cu, Zn, and Pb are higher in the roots with respective values ​​of 4.600±0.001 mg/kg, 345.300±0.019 mg/kg, 3.700±0.001 mg/kg, 38.900±0.005 mg/kg and 2.400±0.002 mg/kg. For cadmium, a value of 0.300±0.001 mg kg-1 is found for stems and leaves, while the roots have a content of 0.200±0.001 mg/kg. The average concentrations of some of the heavy metals analyzed are below the authorized limit in the roots, stems and leaves. The target hazard quotient (THQ) was less than 1 for all heavy metals in roots, stems, and leaves, suggesting that there are no obvious non-cancer health risks associated with the consumption of these medicinal plants, although prolonged use may lead to health risks. The overall hazard factor (HI) is greater than 1 for roots, indicating that the combined effects of heavy metal contaminants in preparation made from the roots of this plant pose a long-term health risk. However, the overall HI for leaves and stems remains less than 1, indicating no health risk for the consumption of preparations made from stems or leaves of this plant. Our current results suggest that medicinal plants contain an acceptable amount of heavy metals and that their use is therefore beneficial in addressing micronutrient deficiencies. Due to the high consumption of plant extracts and the risk of long-term bioaccumulation of heavy metals, monitoring heavy metal concentrations in medicinal plant preparations consumed by patients of traditional practitioners is a health emergency.