title: Environmental behaviour and ecotoxicity of quantum dots at various trophic levels: A review.
abstract: Despite the wide application of quantum dots (QDs) in electronics, pharmacy and nanomedicine, limited data is available on their environmental health risk. To advance our current understanding of the environmental impact of these engineered nanomaterials, the aim of this review is to give a detailed insight on the existing information concerning the behaviour, transformation and fate of QDs in the aquatic environment, as well as on its mode of action (MoA), ecotoxicity, trophic transfer and biomagnification at various trophic levels (micro-organisms, aquatic invertebrates and vertebrates). Data show that several types of Cd-based QDs, even at low concentrations (<mgCdL-1), induce different toxic effects compared to their dissolved counterpart, indicating nano-specific ecotoxicity. QD ecotoxicity at different trophic levels is highly dependent on its physico-chemical properties, environmental conditions, concentration and exposure time, as well as, species, while UV irradiation increases its toxicity. The state of the art regarding the MoA of QDs according to taxonomic groups is summarised and illustrated. Accumulation and trophic transfer of QDs was observed in freshwater and seawater species, while limited biomagnification and detoxification processes were detected. Finally, current knowledge gaps are discussed and recommendations for future research identified. Overall, the knowledge available indicates that in order to develop sustainable nanotechnologies there is an urgent need to develop Cd-free QDs and new "core-shell-conjugate" QD structures.
authors.affiliation: CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal; Laboratory of Cellular Behavior, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil.
authors.forename: Thiago Lopes
authors.initials: TL
authors.lastname: Rocha
authors.affiliation: CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
authors.forename: Nélia C
authors.initials: NC
authors.lastname: Mestre
authors.affiliation: Laboratory of Cellular Behavior, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil.
authors.forename: Simone Maria Teixeira
authors.initials: SM
authors.lastname: Sabóia-Morais
authors.affiliation: CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal. Electronic address: mbebian@ualg.pt.
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Bebianno
mesh_terms: D000818:Animals; D020387:Food Chain; D045663:Quantum Dots / Q000378:metabolism / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity
chemical_list: D014874:Water Pollutants, Chemical
keywords: Aquatic toxicology; Biomarkers; Ecotoxicity; Nanomaterials; Nanoparticles