| Abstract: | Speciation and transformation of Hg was studied in mine wastes collected from abandoned Hg mines at McDermitt, Nevada, and Terlingua, Texas, to evaluate formation of methyl-Hg, which is highly toxic. In these mine wastes, we measured total Hg and methyl-Hg contents, identified various Hg compounds using a pyrolysis technique, and determined rates of Hg methylation and methyl-Hg demethylation using isotopic-tracer methods. Mine wastes contain total Hg contents as high as 14000 ??g/g and methyl-Hg concentrations as high as 88 ng/g. Mine wastes were found to contain variable amounts of cinnabar, metacinnabar, Hg salts, Hg0, and Hg0 and Hg2+ sorbed onto matrix particulates. Samples with Hg0 and matrix-sorbed Hg generally contained significant methyl-Hg contents. Similarly, samples containing Hg0 compounds generally produced significant Hg methylation rates, as much as 26%/day. Samples containing mostly cinnabar showed little or no Hg methylation. Mine wastes with high methyl-Hg contents generally showed low methyl-Hg demethylation, suggesting that Hg methylation was dominant. Methyl-Hg demethylation was by both oxidative and microbial pathways. The correspondence of mine wastes containing Hg0 compounds and measured Hg methylation suggests that Hg0 oxidizes to Hg2+, which is subsequently bioavailable for microbial Hg methylation. |
| Genre: | Conference Paper |
| ProdID: | 70026023 |
| Citation Author: | Gray, J. E.; Hines, M. E.; Biester, H.; Lasorsa, B. K. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | Boutron C.Ferrari C. |
| Citation End Page: | 576 |
| Citation Issue: | I |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Journal De Physique. IV : JP |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 4 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Mercury methylation in mine wastes collected from abandoned mercury mines in the USA; 2003; Conference Paper; Journal De Physique. IV : JP; Gray, J. E.; Hines, M. E.; Biester, H.; Lasorsa, B. K. |
| Citation Start Page: | 573 |
| Citation Volume: | 107 |
| Citation Year: | 2003 |
| Type: | citation/reference |
| Text: | Mercury methylation in mine wastes collected from abandoned mercury mines in the USA; 2003; Conference Paper; Journal De Physique. IV : JP; Gray, J. E.; Hines, M. E.; Biester, H.; Lasorsa, B. K. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Wed, 1 Jan 2003 00:00 -0600 |
| Publisher: | |
