title: Toxicological effects of graphene oxide on adult zebrafish (Danio rerio).
abstract: Graphene exhibits unique physical and chemical properties that facilitate its application in many fields, including electronics and biomedical areas. However, the use of graphene and its derivatives could result in accumulation in aquatic environments, and the risks posed by these compounds for organisms are not completely understood. In this study, we investigated the effects of graphene oxide (GO) on adult zebrafish (Danio rerio). Experimental fish were exposed to 2, 10 or 20mgL-1GO, and the cytotoxicity, genotoxicity and oxidative stress were assessed. The morphology of the gills and liver tissues was also analyzed. Graphene oxide exposure led to an increase in the number of gill cells that were in early apoptotic and necrotic stages, but genotoxicity was not observed in blood cells. We also observed the generation of Reactive Oxygen Species (ROS) in gill cells. Structural analysis revealed injuries to gill tissues, including a dilated marginal channel, lamellar fusion, clubbed tips, swollen mucocytes, epithelial lifting, aneurysms, and necrosis. Liver tissues also presented lesions such as peripherally located nuclei. Furthermore, hepatocytes exhibited a non-uniform shape, picnotic nuclei, vacuole formation, cell rupture, and necrosis. Our results showed that sub-lethal doses of graphene oxide could be harmful to fish species and thus represent risks for the aquatic food chain.
authors.affiliation: Nanomedicine and Nanotoxicology Group, Physics Institute of São Carlos (IFSC), University of São Paulo (USP), São Carlo, SP, Brazil. Electronic address: souza.jaqueline@gmail.com.
authors.forename: Jaqueline P
authors.initials: JP
authors.lastname: Souza
authors.affiliation: Nanomedicine and Nanotoxicology Group, Physics Institute of São Carlos (IFSC), University of São Paulo (USP), São Carlo, SP, Brazil.
authors.forename: Jéssica F
authors.initials: JF
authors.lastname: Baretta
authors.affiliation: Nanomedicine and Nanotoxicology Group, Physics Institute of São Carlos (IFSC), University of São Paulo (USP), São Carlo, SP, Brazil.
authors.forename: Fabrício
authors.initials: F
authors.lastname: Santos
authors.affiliation: Nanomedicine and Nanotoxicology Group, Physics Institute of São Carlos (IFSC), University of São Paulo (USP), São Carlo, SP, Brazil.
authors.forename: Ieda M M
authors.initials: IMM
authors.lastname: Paino
authors.affiliation: Nanomedicine and Nanotoxicology Group, Physics Institute of São Carlos (IFSC), University of São Paulo (USP), São Carlo, SP, Brazil.
authors.forename: Valtencir
authors.initials: V
authors.lastname: Zucolotto
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D004249:DNA Damage; D005260:Female; D005880:Gills / Q000187:drug effects / Q000473:pathology; D006108:Graphite / Q000633:toxicity*; D008099:Liver / Q000187:drug effects / Q000473:pathology; D008297:Male; D018625:Microscopy, Atomic Force; D009153:Mutagens / Q000633:toxicity; D053758:Nanoparticles / Q000633:toxicity / Q000648:ultrastructure; D009336:Necrosis; D017382:Reactive Oxygen Species / Q000378:metabolism; D055672:Static Electricity; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000633:toxicity; D015027:Zebrafish / Q000254:growth & development*
chemical_list: D009153:Mutagens; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; D006108:Graphite
keywords: Carbon nanomaterial; Cytotoxicity; Genotoxicity; Histopathology; Nanoparticle; Oxidative stress