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 as gas. One of the most challenging topics (included in the United Nations Minimata convention) is to 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 been studied, 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 one century, 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 present paper, a new, simple and low-cost method to measure the amount of GEM (Gaseous Elemental Mercury) released from anthropic materials (concrete, wall rocks, and tiles) located in the Hg⁰-rich environments of the former mining site, is proposed. The efficiency of a specific paint that was supposed to act as blocking agent to Hg⁰ was also tested. [ABSTRACT FROM AUTHOR]