Resumo

CARRASQUERO-DURAN, Armando  e  ADAMS, Melitón. Fraccionamiento de mercurio en suelos de áreas contaminadas de el callao, estado bolívar-venezuela. Agronomía Trop. [online]. 2003, vol.53, n.3, pp.331-346. ISSN 0002-192X.

El Callao city at Bolivar State hosts several centers of artisanal gold (Au) mining, where mercury (Hg) is widely employed for Au amalgamation. Although Hg enriched tailings are discharged to soils, little is known about Hg species in soils. Two sequential extraction procedures were applied to determine Hg speciation and derive information about potencial Hg mobility and bioavailability. Soils from mining and non mining areas were sampled, total Hg ranged between 0,2 m g g^-1 and 20,1 m g g-1, the highest values were found in tailing deposits. About 80% of total Hg was strongly bound to organic matter and sulfides, suggesting low mobility. Weaker bound Hg represented less than 10% in more contaminated samples, while in sites with low Hg levels percentage increased to 20%. Soil properties have littie effects on Hg aceumulation.

Palavras-chave : Artisanal mining; organic matter; sulfides; bioavailability; mercury; El Callao; Bolivar; Venezuela.