Insights into reductive dechlorination of triclocarban in river sediments: Field measurements and in~vitro mechanism investigations - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Chemosphere Année : 2016

Insights into reductive dechlorination of triclocarban in river sediments: Field measurements and in~vitro mechanism investigations

Marine Souchier
  • Fonction : Auteur
Valerie Ingrand
  • Fonction : Auteur

Résumé

Triclocarban (TCC) reductive dechlorination was investigated using a combination of field and laboratory experiments. Field monitoring revealed that TCC reductive dechlorination in river sediments leads to formation of two isomers of its lesser chlorinated congener namely 3,4'-dichlorocarbanilide and 4,4'-dichlorocarbanilide. Monochlorocarbanilide was not detected in sediments supporting that transformation of dichlorocarbanilide into monochlorocarbanilide is the rate limiting step of TCC dechlorination. In~vitro experiments were conducted to study TCC potential reductive dechlorination mechanisms. These experiments demonstrated that 4,4'-dichlorocarbanilide was specifically formed upon a nucleophilic addition reaction under anaerobic conditions. The 3,4'-diclorocarbanilide was formed upon a two steps radical mechanism under aerobic conditions which includes TCC activation by one electron oxidation followed by a nucleophilic substitution reaction with glutathione. In~vitro results suggested that strict anaerobic conditions might not be required for TCC reductive dechlorination in the environment. Moreover, in~vitro reactions were performed using biomimetic or enzymatic systems supposing that TCC dechlorination might occur through microbial action in situ. Measured dichlorocarbanilide isomers/triclocarban ratios were used to evaluate the relative significance of both dechlorination pathways and the pathway leading to 3,4'-dichlorocarbanilide was found significant in all investigated river sediment samples.
Fichier non déposé

Dates et versions

hal-02086690 , version 1 (01-04-2019)

Identifiants

Citer

Marine Souchier, Claude Casellas, Valerie Ingrand, Serge Chiron. Insights into reductive dechlorination of triclocarban in river sediments: Field measurements and in~vitro mechanism investigations. Chemosphere, 2016, 144, pp.425--432. ⟨10.1016/j.chemosphere.2015.08.083⟩. ⟨hal-02086690⟩
23 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More