Levels of Lead in Selected Common Medicinal Plants Growing Along Roadside in Leyte

Abstract

Lead, as an important environmental pollutant from vehicular emission, is generally the largest source of heavy metal contamination in roadside ecosystems. Ten common Philippine medicinal plants namely: Allium fistulosum, Artemisia vulgaris, Basella alba, Ipomoea batatas, Euphorbia hirta, Plectranthus amboinicus, Mimosa pudica, Cymbopogon citratus, Portulaca oleracea, and Curcuma longa growing along the 45-km stretch of the Baybay – Ormoc national highway were investigated for Pb accumulation. The study showed Curcuma longa, Plectranthus amboinicus, and Artemisia vulgaris had the highest Pb content in the leaves. In the stem, Mimosa pudica had the lowest with 5.0 mg/kg while Plectranthu samboinicus had the highest with 9.5 mg/kg. In the roots, Pb was highest (18.0 mg/kg) in Allium fistulosum but low (below 10.0 mg/kg) in all the other species. Results imply that consumption of medicinal plants growing along busy roads may not be safe, especially those species that accumulate high levels of Pb. Long term usage of these plants may cause serious health problems