A New Low-Cost and Reliable Method to Evaluate the Release of Hg0 from Synthetic Materials

Mercury is a toxic and noxious element and is the only metal that naturally occurs asgas. One of the most challenging topics (included in the United Nations Minimata convention) isto understand the adsorption-release processes of manmade materials (e.g., concrete, bricks, tiles,painting). Adsorption of Hg by construction and demolition waste materials has recently beenstudied, but investigations on how much Hg0 can be released from these products are rather poor.The abandoned mining site of Abbadia San Salvatore (Siena, central Italy) where, for about onecentury, cinnabar was roasted to produce liquid mercury, is known for the high concentrations of(i) Hg0 in edifices and structures and (ii) total and leachate Hg in synthetic materials. In the presentpaper, a new, simple and low-cost method to measure the amount of GEM (Gaseous ElementalMercury) released from anthropic materials (concrete, wall rocks, and tiles) located in the Hg0-richenvironments of the former mining site, is proposed. The eciency of a specific paint that wassupposed to act as blocking agent to Hg0 was also tested.