Artisanal and small-scale gold mining (ASGM) is the largest sector of demand for mercury (Hg), and therefore,
one of the major sources of Hg pollution in the environment. This study was conducted in the Alacrán goldmining
site, one of the most important ASGM sites in Colombia, to identify native plant species growing in Hgcontaminated
soils used for agricultural purposes, and to assess their potential as phytoremediation systems.
Twenty-four native plant species were identified and analysed for total Hg (THg) in different tissues (roots,
stems, and leaves) and in underlying soils. Accumulation factors (AF) in the shoots, translocation (TF) from
roots to shoots, and bioconcentration (BCF) from soil-to-roots were determined. Different tissues from all
plant species were classified in the order of decreasing accumulation of Hg as follows: roots N leaves N stems.
THg concentrations in soil ranged from 230 to 6320 ng g−1. TF values varied from 0.33 to 1.73, with high values
in the lower Hg-contaminated soils. No correlation was found between soils with low concentrations of Hg and
plant leaves, indicating that TF is not a very accurate indicator, sincemost of the Hg input to leaves at ASGMsites
comes fromthe atmosphere. On the other hand, the BCF ranged from 0.28 to 0.99, with Jatropha curcas showing
the highest value. Despite their low biomass production, several herbs and sub-shrubs are suitable for
phytoremediation application in the field, due to their fast growth and high AF values in large and easily harvestable
plant parts. Among these species, herbs such as Pipermarginathumand Stecherus bifidus, and the sub-shrubs