Numéro |
J. Phys. IV France
Volume 107, May 2003
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Page(s) | 267 - 270 | |
DOI | https://doi.org/10.1051/jp4:20030293 |
J. Phys. IV France 107 (2003) 267
DOI: 10.1051/jp4:20030293
Temporal and spatial bioassessment of ecological risk of Amazonian Itchyofauna associated to Hg exposure
Z.C. Castilhos1, N. Almonsy2, P.S. Souto3, L.C.C. Pereira da Silva2 and E.D. Bidone21 Center for Mineral Technology-CETEM, Avenida Ipê 900, llha da Cidade Universitaria, Rio de Janeiro-RJ 21941-590, Brazil
2 Fluminense Federal University
3 FCAP-Soil Sciences College of Para State
Abstract
In Amazon artisan gold mining, mercury (Hg) is released to environment during its use to
amalgamate the fine particles of gold. Once mercury entries in aquatic ecosystems, it might be
methylated to methylmercury (MeHg). The objectives of this work were: (i) to establish and compare
the dose-response relationship for Hg accumulation by Tucunaré for a contaminated and a background
area; (ii) to test the DRAC methodology to proceed field sampling of fish; (iii) to conduct a temporal
analysis of magnitude of mercury contamination in fish during the last decade by using DRAC
methodology and (v) to investigate the relationship between hematological parameters (erythrocytes,
hematocrit, leukocytes and mean corpuscular volume) and Hg exposure in fish.. Close to 100
Tucunarés were caught in the Tapajós River region. The results showed significant differences in
hematological parameters and Hg concentration considering contaminated and background areas and
the temporal assessment suggest increase the Hg bio-availability during last decade in Tapajos River
Region. One could suggest that those hematological parameters might be used as physiological
biomarkers of Hg exposure in ecological risk assessment process and that Hg used by or remaining
from gold mining "garimpos" might be continuous bio-available to Amazonian biota.
© EDP Sciences 2003