title: Organotin persistence in contaminated marine sediments and porewaters: In situ degradation study using species-specific stable isotopic tracers.
abstract: This paper provides a comprehensive study of the persistence of butyltins and phenyltins in contaminated marine sediments and presents the first data on their degradation potentials in porewaters. The study's aim was to explain the different degradation efficiencies of organotin compounds (OTC) in contaminated sediments. The transformation processes of OTC in sediments and porewaters were investigated in a field experiment using species-specific, isotopically enriched organotin tracers. Sediment characteristics (organic carbon content and grain size) were determined to elucidate their influence on the degradation processes. The results of this study strongly suggest that a limiting step in OTC degradation in marine sediments is their desorption into porewaters because their degradation in porewaters occurs notably fast with half-lives of 9.2 days for tributyltin (TBT) in oxic porewaters and 2.9±0.1 and 9.1±0.9 days for dibutyltin (DBT) in oxic and anoxic porewaters, respectively. By controlling the desorption process, organic matter influences the TBT degradation efficiency and consequently defines its persistence in contaminated sediments, which thus increases in sediments rich in organic matter.
authors.affiliation: Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, Zagreb, Croatia.
authors.forename: Martina
authors.initials: M
authors.lastname: Furdek
authors.affiliation: Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, Zagreb, Croatia.
authors.forename: Nevenka
authors.initials: N
authors.lastname: Mikac
authors.affiliation: Laboratoire de Chimie Analytique Bio-inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux, CNRS UMR 5254, Université de Pau et des Pays de l'Adour, Hélioparc Pau Pyrénées, 2, Av. P. Angot, 64053 Pau Cedex 9, France.
authors.forename: Maite
authors.initials: M
authors.lastname: Bueno
authors.affiliation: Laboratoire de Chimie Analytique Bio-inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux, CNRS UMR 5254, Université de Pau et des Pays de l'Adour, Hélioparc Pau Pyrénées, 2, Av. P. Angot, 64053 Pau Cedex 9, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Tessier
authors.affiliation: Laboratoire de Chimie Analytique Bio-inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux, CNRS UMR 5254, Université de Pau et des Pays de l'Adour, Hélioparc Pau Pyrénées, 2, Av. P. Angot, 64053 Pau Cedex 9, France.
authors.forename: Joana
authors.initials: J
authors.lastname: Cavalheiro
authors.affiliation: Laboratoire de Chimie Analytique Bio-inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux, CNRS UMR 5254, Université de Pau et des Pays de l'Adour, Hélioparc Pau Pyrénées, 2, Av. P. Angot, 64053 Pau Cedex 9, France. Electronic address: mathilde.monperrus@univ-pau.fr.
authors.forename: Mathilde
authors.initials: M
authors.lastname: Monperrus
keywords: Degradation kinetics; Isotopically enriched tracers; Organic matter; Organotin compounds; Sediments; Tributyltin