A study of soil pollution by lead in the margins of Albarregas river (Mérida, Venezuela) using dandelion (Taraxacum officinale) as a bioindicator

Concentrations of heavy metals in the environment may be due primarily to natural and anthropogenic causes, which could generate bioaccumulation in a biological organism. Since scientific studies made in several countries have shown the presence of lead (Pb) in plants as a result of environmental reuptake, they have been proposed as both biomonitors of pollution and bioindicators of environmental risk. In this regard, the species Taraxacum officinale (dandelion) is an attractive candidate for biological monitoring of heavy metals. For this reason, the presence of Pb in Taraxacum officinale plants recollected on the banks of the Albarregas River, Mérida, Venezuela was investigated. The obtained results indicate that the Pb content in plants collected in these soils is significantly different from that obtained from plants growing in soils not exposed to contamination. There was also evidence that Pb concentrations were higher than the maximum level recommended by the WHO and that considered background level, which allows us to infer that the presence of Pb in this herb comes from the soil uptake process, so this should not be recommended as a medicinal plant.