Our research is increasingly showing that antimony (Sb) is a global environmental contaminant whose significance has until now been underestimated. In fact, the environmental importance of Sb is on par with such elements as lead (Pb), mercury (Hg), or cadmium (Cd), but this is generally not appreciated. In contrast to these other elements, far less is known about the sources, behaviour, and ultimate fate of Sb in the environment.
Antimony is considered a "priority pollutant" by the German Science Foundation (DFG), the European Commission, as well as the U.S. Environmental Protection Agency. Antimony (Sb, from the Latin stibium), is commonly found in lead ores. Therefore, the mining and refining of Pb over the millenia has not only given rise to extensive Pb contamination, but Sb contamination as well. Our research suggests that the sum of all emissions of Sb to the global environment may be a factor of ten greater than those from natural sources. In other words, human activities are dominating the driving the global Sb cycle and the effects of these activities on the global cycling of Sb are comparable to the impacts we have had on the global Pb cycle.
Why is Sb relevant today? First, Sb, like As and Pb, has no physiological function and is potentially toxic. However, far less is known about Sb in the environment and in human health simply because Sb has received much less attention than either of these two elements.
Second, there are many significant anthropogenic sources of Sb to the environment today and some are actually increasing in importance. Antimony is emitted from coal combustion as well as the smelting, refining, and recycling of Pb, Cu, and Zn ores. However, Sb is of particular concern in urban areas because of the growing importance of waste incineration (Sb is used to make flame-resistant plastics, but also in electronics, pigments, enamels, alloys, and as a catalyst to manufacture diverse polymers including PET) and vehicular traffic (it is alloyed with Pb in lead acid batteries, in heat-resistant plastics for electronic components, and in the linings of brake shoes).
The mineralogical and chemical forms of Sb in soils, and the aqueous speciation of Sb in soil solutions and surface waters, are poorly understood. Antimony may be more mobile than Pb because Sb oxides are more soluble than those of Pb, and because the dominant inorganic species in soil waters is a negatively charged anion. For similar reasons, Sb may be more "accessible" to living organisms.