Assessment of Hg contamination by a Chlor-Alkali Plant in riverine and coastal sites combining Hg speciation and isotopic signature (Sagua la Grande River, Cuba)

• Published in: Journal of Hazardous Materials
• Main Authors: Feng, Caiyan, Pedrero, Zoyne, Lima, Lázaro, Olivares, Susana, de La Rosa, Daniel, Bérail, Sylvain, Tessier, Emmanuel, Pannier, Florence, Amouroux, David
• Other Authors: Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS), ANR-11-CESA-0013,RIMNES,Les Rapports Isotopiques du Mercure et les biomarqueurs Notch/apoptose : de nouveaux outils à l'interface Environnement - Santé(2011)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Biota; Mercury isotopic fractionation; Chlor–alkali plant; Sediment; Methylmercury; [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry; [CHIM.ANAL]Chemical Sciences/Analytical chemistry; [CHIM.POLY]Chemical Sciences/Polymers; [CHIM.MATE]Chemical Sciences/Material chemistry; La Grande River
• Online Access: https://hal.science/hal-02078082; https://hal.science/hal-02078082/document; https://hal.science/hal-02078082/file/UncorrectedProofpagination_HAZMAT_20361.pdf; https://doi.org/10.1016/j.jhazmat.2019.02.092

International audience Chlor–alkali plants (CAP) are recognized as major sources of mercury (Hg) in the environment. In this work, Hg concentration, speciation and isotopic signature were determined in sediments and biota (fish and oyster) from Sagua La Grande River (SG River) and the adjacent coastal zone in the vicinity of a CAP (Cuba). High Hg concentrations in surface sediments (up to 5072 ng g −1 ), mainly occurring as inorganic Hg, decrease with the distance from the CAP along the SG River and seaward. Meanwhile, Hg concentration and speciation in riverine catfish (Claria gariepinus) muscle (1093 ± 319 ng g −1 , ˜70% as MeHg) and coastal oysters (Crassostrea rizophorae) (596 ± 233 ng g −1 , ˜50% as MeHg) indicate a direct impact from CAP. Hg isotopic signature in sediments, following both mass dependent (MDF) and mass independent fractionation (MIF), exhibits a clear binary mixing between CAP pollution (+0.42‰ δ 202 Hg; -0.18‰ Δ 201 Hg) and regional background end-member (˜ -0.49‰ δ 202 Hg; +0.01‰ Δ 201 Hg). The combination of speciation and isotopic information in biota and sediments allows to trace Hg contamination pathways from contaminated sediments to the biota, establishing the importance of both methylation and demethylation extent in both river and coastal sites before Hg species bioaccumulatio