Seasonal behavior of mercury species in waters and sediments from the Negro River Basin, Amazon, Brazil

Author(s)

Márcia Cristina Bisinoti ^[1] ; Ézio Sargentini Júnior ^[2] ; Wilson F. Jardim ^[3]

Affiliation

^[1] Universidade Estadual Paulista. Instituto de Biociências, Letras e Ciências Exatas. Departamento de Química e Ciências Ambientais - Brasil

^[2] Instituto Nacional de Pesquisas da Amazônia. Coordenação de Pesquisas em Produtos Naturais, Química Analítica Ambiental - Brasil

^[3] Universidade Estadual de Campinas. Instituto de Química. Departamento de Química Analítica - Brasil

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 18, n. 3, p. 544-553, 2007-00-00.

Abstract

Total (HgT), reactive (HgR) and organic (HgORG) mercury species have been quantified in non-filtered waters collected from the Negro River Basin, Amazon (from January/2002 through January/2004), in both black and white water bodies. Black waters presented the highest HgT, HgORG and HgR concentration (29.1 ng L-1, 1.63 ng L-1 and 3.9 ng L-1, respectively), while, white waters presented the lowest HgT, HgORG and HgR concentration (8.8 ng L-1, 0.49 ng L-1 and 1.2 ng L-1, respectively). An inverse correlation between HgT and the water level over the basin was obtained, although the HgORG concentration has increased in the first rainy months and then decreased as the water level rose. Total mercury in surface sediments (0-10 cm) ranged from 70 to 271 mg kg-1 being the methylmercury 0.47-1.79 % of this stock.The results indicate that HgR and the labile dissolved organic matter were introduced into the aquatic environment during the flooding season, especially in the earlier stages, thus contributing to mercury methylation. (AU)

• FAPESP's process: 00/13517-1 - Mercury fluxes in the Rio Negro Basin, Amazon
• Grantee: Wilson de Figueiredo Jardim
• Support Opportunities: Research Projects - Thematic Grants