"Nanosize effect" in the metal-handling strategy of the bivalve Scrobicularia plana exposed to CuO nanoparticles and copper ions in whole-sediment toxicity tests.

Autor: Scola S; Departamento de Ecología y Gestión Costera - Instituto sde Ciencias Marinas de Andalucía (CSIC), Campus Rio San Pedro, 11510 Puerto Real, Cádiz, Spain., Blasco J; Departamento de Ecología y Gestión Costera - Instituto sde Ciencias Marinas de Andalucía (CSIC), Campus Rio San Pedro, 11510 Puerto Real, Cádiz, Spain., Campana O; Universidad de Cádiz, INMAR, Campus Rio San Pedro, 11510 Puerto Real, Spain. Electronic address: olivia.campana@icman.csic.es.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2021 Mar 15; Vol. 760, pp. 143886. Date of Electronic Publication: 2020 Dec 03.
DOI: 10.1016/j.scitotenv.2020.143886
Abstrakt: To date, the occurrence, fate and toxicity of metal-based NPs in the environment is under investigated. Their unique physicochemical, biological and optical properties, responsible for their advantageous application, make them intrinsically different from their bulk counterpart, raising the issue of their potential toxic specificity or "nanosize effect". The aim of this study was to investigate copper bioaccumulation, subcellular distribution and toxic effect in the marine benthic species Scrobicularia plana exposed to two forms of sediment-associated copper, as nanoparticles (CuO NPs) and as soluble ions (CuCl 2 ). Results showed that the exposure to different copper forms activated specific organism's metal handling strategies. Clams bioaccumulated soluble copper at higher concentrations than those exposed to sediment spiked with CuO NPs. Moreover, CuO NPs exposure elicited a stronger detoxification response mediated by a prompt mobilization of CuO NPs to metal-containing granules as well as a delayed induction of MT-like proteins, which conversely, sequestered soluble copper since the beginning of the exposure at levels significantly different from the control. Eventually, exposure to high concentrations of either copper form led to the same acute toxic effect (100% mortality) but the outcome was delayed in bivalves exposed to CuO NPs suggesting that the mechanisms underlying toxicity were copper form-specific. Indeed, while most of soluble copper was associated to the mitochondrial fraction suggesting an impairment of the ATP synthesis capacity at mitochondrial level, CuO NPs toxicity was most likely caused by the oxidative stress mediated by their bioaccumulation in the enzymatic and mitochondrial metabolically available fractions.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2020 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
Externí odkaz: