title: Assessment of toxicity and genotoxicity of low doses of 5-fluorouracil in zebrafish (Danio rerio) two-generation study.
abstract: Residues of anti-neoplastic drugs represent new and emerging pollutants in aquatic environments. Many of these drugs are genotoxic, and it has been postulated that they can cause adverse effects in aquatic ecosystems. 5-Fluorouracil (5-FU) is one of the most extensively used anti-neoplastic drugs in cancer therapy, and this article describes the results of the first investigation using a two-generation toxicity study design with zebrafish (Danio rerio). Exposure of zebrafish to 5-FU (0.01, 1.0 and 100 μg/L) was initiated with adult zebrafish (F0 generation) and continued through the hatchings and adults of the F1 generation, and the hatchings of the F2 generation, to day 33 post-fertilisation. The exposure did not affect survival, growth and reproduction of the zebrafish; however, histopathological changes were observed in the liver and kidney, along with genotoxic effects, at all 5-FU concentrations. Increases in DNA damage determined using the comet assay were significant in the liver and blood cells, but not in the gills and gonads. In erythrocytes, a significant, dose-dependent increase in frequency of micronuclei was observed at all 5-FU concentrations. Whole genome transcriptomic analysis of liver samples of F1 generation zebrafish exposed to 0.01 μg/L and 1 μg/L 5-FU revealed dose-dependent increases in the number of differentially expressed genes, including up-regulation of several DNA-damage-responsive genes and oncogenes (i.e., jun, myca). Although this chronic exposure to environmentally relevant concentrations of 5-FU did not affect the reproduction of the exposed zebrafish, it cannot be excluded that 5-FU can lead to degenerative changes, including cancers, which over long-term exposure of several generations might affect fish populations. The data from this study contribute to a better understanding of the potential consequences of chronic exposure of fish to low concentrations of anti-neoplastic drugs, and they demonstrate that further studies into multi-generation toxicity are needed.
authors.affiliation: Department of Aquaculture, Institute of Aquaculture and Environmental Safety, Faculty of Agricultural and Environmental Sciences, Szent István University, 1. Pater Károly St., H-2100 Gödöllo, Hungary.
authors.forename: Róbert
authors.initials: R
authors.lastname: Kovács
authors.affiliation: Department of Aquaculture, Institute of Aquaculture and Environmental Safety, Faculty of Agricultural and Environmental Sciences, Szent István University, 1. Pater Károly St., H-2100 Gödöllo, Hungary.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Csenki
authors.affiliation: Department of Aquaculture, Institute of Aquaculture and Environmental Safety, Faculty of Agricultural and Environmental Sciences, Szent István University, 1. Pater Károly St., H-2100 Gödöllo, Hungary.
authors.forename: Katalin
authors.initials: K
authors.lastname: Bakos
authors.affiliation: Department of Aquaculture, Institute of Aquaculture and Environmental Safety, Faculty of Agricultural and Environmental Sciences, Szent István University, 1. Pater Károly St., H-2100 Gödöllo, Hungary.
authors.forename: Béla
authors.initials: B
authors.lastname: Urbányi
authors.affiliation: Department of Aquaculture, Institute of Aquaculture and Environmental Safety, Faculty of Agricultural and Environmental Sciences, Szent István University, 1. Pater Károly St., H-2100 Gödöllo, Hungary.
authors.forename: Ákos
authors.initials: Á
authors.lastname: Horváth
authors.affiliation: Mutagenesis Unit, Institute for Medical Research and Occupational Health, Ksaverska cesta 2, 10000 Zagreb, Croatia.
authors.forename: Vera
authors.initials: V
authors.lastname: Garaj-Vrhovac
authors.affiliation: Mutagenesis Unit, Institute for Medical Research and Occupational Health, Ksaverska cesta 2, 10000 Zagreb, Croatia.
authors.forename: Goran
authors.initials: G
authors.lastname: Gajski
authors.affiliation: Mutagenesis Unit, Institute for Medical Research and Occupational Health, Ksaverska cesta 2, 10000 Zagreb, Croatia.
authors.forename: Marko
authors.initials: M
authors.lastname: Gerić
authors.affiliation: Water and Soil Quality Research Group, Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18-26, E-08034 Barcelona, Spain.
authors.forename: Noelia
authors.initials: N
authors.lastname: Negreira
authors.affiliation: Water and Soil Quality Research Group, Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18-26, E-08034 Barcelona, Spain.
authors.forename: Miren
authors.initials: M
authors.lastname: López de Alda
authors.affiliation: Water and Soil Quality Research Group, Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18-26, E-08034 Barcelona, Spain; Catalan Institute for Water Research (ICRA), H(2)O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain.
authors.forename: Damià
authors.initials: D
authors.lastname: Barceló
authors.affiliation: Institute Jožef Stefan, Jadranska 29, 1000 Ljubljana, Slovenia.
authors.forename: Ester
authors.initials: E
authors.lastname: Heath
authors.affiliation: Institute Jožef Stefan, Jadranska 29, 1000 Ljubljana, Slovenia.
authors.forename: Tina
authors.initials: T
authors.lastname: Kosjek
authors.affiliation: National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Bojana
authors.initials: B
authors.lastname: Žegura
authors.affiliation: National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia; Ecological Engineering Institute, Ljubljanska 9, 2000 Maribor, Slovenia; Jozef Stefan International Postgraduate School, Jamova cesta 39, 1000 Ljubljana, Slovenia.
authors.forename: Matjaž
authors.initials: M
authors.lastname: Novak
authors.affiliation: National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Irena
authors.initials: I
authors.lastname: Zajc
authors.affiliation: National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Špela
authors.initials: Š
authors.lastname: Baebler
authors.affiliation: National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Ana
authors.initials: A
authors.lastname: Rotter
authors.affiliation: National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Živa
authors.initials: Ž
authors.lastname: Ramšak
authors.affiliation: National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia. Electronic address: metka.filipic@nib.si.
authors.forename: Metka
authors.initials: M
authors.lastname: Filipič
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000633:toxicity*; D001773:Blood Cells / Q000187:drug effects; D020552:Comet Assay; D004249:DNA Damage / Q000187:drug effects; D005472:Fluorouracil / Q000633:toxicity*; D020869:Gene Expression Profiling; D005880:Gills / Q000187:drug effects; D006066:Gonads / Q000187:drug effects; D007668:Kidney / Q000187:drug effects / Q000473:pathology; D008099:Liver / Q000187:drug effects / Q000473:pathology; D012098:Reproduction / Q000187:drug effects; D036401:Toxicity Tests, Chronic; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015027:Zebrafish / Q000235:genetics / Q000254:growth & development*
chemical_list: D000964:Antimetabolites, Antineoplastic; D014874:Water Pollutants, Chemical; D005472:Fluorouracil
keywords: 5-Fluorouracil; Anticancer drugs; Chronic exposure; Danio rerio; Genotoxic; Toxicogenomic