title: Regional distribution of mercury in sediments of the main rivers of French Guiana (Amazonian basin).
abstract: Use of mercury (Hg) for gold-mining in French Guiana (up until 2006) as well as the presence of naturally high background levels in soils, has led to locally high concentrations in soils and sediments. The present study maps the levels of Hg concentrations in river sediments from five main rivers of French Guiana (Approuague River, Comté River, Mana River, Maroni River and Oyapock River) and their tributaries, covering more than 5 450 km of river with 1 211 sampling points. The maximum geological background Hg concentration, estimated from 241 non-gold-mined streams across French Guiana was 150 ng g(-1). Significant differences were measured between the five main rivers as well as between all gold-mining and pristine areas, giving representative data of the Hg increase due to past gold-mining activities. These results give a unique large scale vision of Hg contamination in river sediments of French Guiana and provide fundamental data on Hg distribution in pristine and gold-mined areas.
authors.affiliation: BRGM, D3E, Water, Environment and Ecotechnology Division, 3 avenue Claude Guillemin, BP 36009, 45060 Orléans, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Laperche
authors.affiliation: BRGM, D3E, Water, Environment and Ecotechnology Division, 3 avenue Claude Guillemin, BP 36009, 45060 Orléans, France.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Hellal
authors.affiliation: UMR CNRS 5805 EPOC - OASU Station Marine d'Arcachon, Université Bordeaux 1, Place du Docteur Bertrand Peyneau, 33120 Archachon, France.
authors.forename: Régine
authors.initials: R
authors.lastname: Maury-Brachet
authors.affiliation: French Geological Survey (BRGM), Direction régionale Guyane, Domaine de Suzini, Route de Montabo, BP 552, 97333 Cayenne cedex, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Joseph
authors.affiliation: French Geological Survey (BRGM), Direction régionale Guyane, Domaine de Suzini, Route de Montabo, BP 552, 97333 Cayenne cedex, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Laporte
authors.affiliation: BRGM, D3E, Water, Environment and Ecotechnology Division, 3 avenue Claude Guillemin, BP 36009, 45060 Orléans, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Breeze
authors.affiliation: BRGM, D3E, Water, Environment and Ecotechnology Division, 3 avenue Claude Guillemin, BP 36009, 45060 Orléans, France.
authors.forename: François
authors.initials: F
authors.lastname: Blanchard
keywords: French Guiana; Gold-mining; Mercury; Sediments