Antimony distribution in soils and plants near an abandoned mining site

A study about antimony distribution and mobility in soils located in the surroundings of an abandoned mining site is carried out. The mineralogical composition of the soils is obtained, and the samples classified into three groups attempting to correlate antimony level and behavior with the main mineral phases present. The total antimony concentrations are measured (5-40 mg kg⁻¹), and mobility of the metalloid is assessed by using selective extractants. Maximum mobility is obtained when extracting with a reducing-complexing medium which, taking into account the characteristics of the zone, means antimony availability to plants should be low. This is verified by analyzing both roots and leaves of vegetation growing in the area. The maximum level present in the leaves is 1.5 mg kg⁻¹ dry matter, but most of the samples show antimony concentrations below 0.5 mg kg⁻¹. The results indicate that plants represent an effective barrier to antimony that is incorporated only in small proportions, and so the risk posed to biota is low.