This study examines total Hg, free Hg(0), matrix-bound Hg and MeHg contents in soils and plant tissues from two
old cinnabar mining sites (La Soterraña and Los Rueldos) in Asturias (Spain), as well as Hg transfer and translo
cation from soils to plants. The studied soils from both mines accumulated moderate to very high total Hg con
centrations (36–1709 mg·kg − 1) but quite low available Hg contents (0.005–3.062 mg·kg − 1) which resulted
in relatively low transfer factor values. Matrix-bound Hg was the prevalent Hg form in soils from both mining
sites representing 67–88% of total Hg content. Significant Hg(0) concentrations were found in soils as a conse
quence of atmospheric deposition. Appreciable MeHg concentrations were found in soils from La Soterraña min
ing site while non-detectable MeHg could be found in soils from Los Rueldos. All the studied plants can be
considered as excluders. Hg(0) is practically absent in roots indicating that this Hg form is not uptaken from
soils. Hg(0) contents found in aboveground tissues evidenced that foliar uptake of atmospheric Hg occurs. Signif
icant MeHg contents were found in the aerial parts for all studied plants. However, MeHg contents in roots were
extremely low in La Soterraña plants and non-detectable in those from Los Rueldos