title: Early warning signs of endocrine disruption in adult fish from the ingestion of polyethylene with and without sorbed chemical pollutants from the marine environment.
abstract: Plastic debris is associated with several chemical pollutants known to disrupt the functioning of the endocrine system. To determine if the exposure to plastic debris and associated chemicals promotes endocrine-disrupting effects in fish, we conducted a chronic two-month dietary exposure using Japanese medaka (Oryzias latipes) and environmentally relevant concentrations of microplastic (<1mm) and associated chemicals. We exposed fish to three treatments: a no-plastic (i.e. negative control), virgin-plastic (i.e. virgin polyethylene pre-production pellets) and marine-plastic treatment (i.e. polyethylene pellets deployed in San Diego Bay, CA for 3 months). Altered gene expression was observed in male fish exposed to the marine-plastic treatment, whereas altered gene expression was observed in female fish exposed to both the marine- and virgin-plastic treatment. Significant down-regulation of choriogenin (Chg H) gene expression was observed in males and significant down-regulation of vitellogenin (Vtg I), Chg H and the estrogen receptor (ERα) gene expression was observed in females. In addition, histological observation revealed abnormal proliferation of germ cells in one male fish from the marine-plastic treatment. Overall, our study suggests that the ingestion of plastic debris at environmentally relevant concentrations may alter endocrine system function in adult fish and warrants further research.
authors.affiliation: Aquatic Health Program, School of Veterinary Medicine, University of California, Davis, Davis, CA 95616, USA. Electronic address: cmrochman@ucdavis.edu.
authors.forename: Chelsea M
authors.initials: CM
authors.lastname: Rochman
authors.affiliation: Aquatic Health Program, School of Veterinary Medicine, University of California, Davis, Davis, CA 95616, USA.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Kurobe
authors.affiliation: Aquatic Health Program, School of Veterinary Medicine, University of California, Davis, Davis, CA 95616, USA.
authors.forename: Ida
authors.initials: I
authors.lastname: Flores
authors.affiliation: Aquatic Health Program, School of Veterinary Medicine, University of California, Davis, Davis, CA 95616, USA.
authors.forename: Swee J
authors.initials: SJ
authors.lastname: Teh
mesh_terms: D000818:Animals; D015536:Down-Regulation; D052244:Endocrine Disruptors / Q000378:metabolism / Q000633:toxicity*; D004703:Endocrine System / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D008297:Male; D009990:Oryzias / Q000502:physiology; D020959:Polyethylene / Q000378:metabolism / Q000633:toxicity*; D014819:Vitellogenins / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity*
chemical_list: D052244:Endocrine Disruptors; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D020959:Polyethylene
keywords: Endocrine disruption; Gene expression; Germ cells; Japanese medaka; Plastic debris