Arsenic-bearing calcite in natural travertines: evidence from sequential extraction, µXAS, and µXRF.
Environ Sci Technol
; 47(12): 6231-8, 2013 Jun 18.
Article
in En
| MEDLINE
| ID: mdl-23738848
Recent studies demonstrated that synthetic calcite may host considerable amounts of arsenic (As). In this paper, the concentration of As in natural calcite was determined using two novel, specifically designed, sequential extraction procedures. In addition, the oxidation state of As and its distribution between calcite and coexisting Fe-oxyhydroxides was unravelled by µXRF elemental mapping and As K-edge µXAS spectroscopy. Our results conclusively demonstrate that arsenic can be found in natural calcite up to 2 orders of magnitude over the normal crustal As abundances. Because of the large diffusion of calcite in the environment, this phase may exert an important control on As geochemistry, mobility, and bioavailability.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Arsenic
/
Calcium Carbonate
Language:
En
Journal:
Environ Sci Technol
Year:
2013
Document type:
Article
Affiliation country:
Italy
Country of publication:
United States