title: Biomarker responses and chemical analyses in fish indicate leakage of polycyclic aromatic hydrocarbons and other compounds from car tire rubber.
abstract: Rubber tire material contains toxic compounds including oils rich in polycyclic aromatic hydrocarbons (PAH), so-called highly aromatic (HA) oils, as well as other reactive additives used as antioxidants, antiozonants, and vulcanization accelerators. The toxicity of rubber tire leachates to aquatic organisms has been demonstrated before. However, previous studies have focused on lethal rather than sublethal effects. We kept rainbow trout (Oncorhynchus mykiss) in tanks with two types of tires: a tire containing HA oils in the tread or a tire free of HA oils in the tread. After 1 d of exposure, an induction of cytochrome P4501A1 (CYP1A1) was evident in both exposed groups, measured as elevated ethoxyresorufin-O-deethylase (EROD) activity and increased CYP1A1 mRNA levels. After two weeks of exposure, EROD activity and CYP1A1 mRNA were still high in fish exposed to leachate from HA oil-containing tire, whereas the effect was somewhat lower in fish exposed to leachate from HA oil-free tread tire. Compounds in the tire leachates also affected antioxidant parameters. Total glutathione concentration in liver as well as hepatic glutathione reductase, glutathione S-transferase, and glucose-6-phosphate dehydrogenase activities were markedly elevated after two weeks of exposure in both groups. The responses were greater in the group exposed to leachate from HA oil-free tread tire. Vitellogenin measurements did not indicate leakage of estrogenic compounds from the tires. Chemical analyses of bile from exposed fish revealed the presence of hydroxylated PAH as well as aromatic nitrogen compounds indicating uptake of these compounds by the fish.
authors.affiliation: Department of Zoology/Zoophysiology, Göteborg University, Box 463, SE 40530 Göteborg, Sweden.
authors.forename: Eiríkur
authors.initials: E
authors.lastname: Stephensen
authors.forename: Margaretha
authors.initials: M
authors.lastname: Adolfsson-Erici
authors.forename: Malin
authors.initials: M
authors.lastname: Celander
authors.forename: Mats
authors.initials: M
authors.lastname: Hulander
authors.forename: Jari
authors.initials: J
authors.lastname: Parkkonen
authors.forename: Tove
authors.initials: T
authors.lastname: Hegelund
authors.forename: Joachim
authors.initials: J
authors.lastname: Sturve
authors.forename: Linda
authors.initials: L
authors.lastname: Hasselberg
authors.forename: Madeleine
authors.initials: M
authors.lastname: Bengtsson
authors.forename: Lars
authors.initials: L
authors.lastname: Förlin
mesh_terms: D000818:Animals; D001646:Bile / Q000737:chemistry; D015415:Biomarkers / Q000032:analysis*; D019363:Cytochrome P-450 CYP1A1 / Q000032:analysis*; D004781:Environmental Exposure; D005978:Glutathione / Q000032:analysis; D008420:Manufactured Materials; D017686:Oncorhynchus mykiss / Q000502:physiology*; D018384:Oxidative Stress; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000506:poisoning*; D012333:RNA, Messenger / Q000032:analysis; D012408:Rubber / Q000737:chemistry*; D014018:Tissue Distribution
chemical_list: D015415:Biomarkers; D011084:Polycyclic Aromatic Hydrocarbons; D012333:RNA, Messenger; D012408:Rubber; D019363:Cytochrome P-450 CYP1A1; D005978:Glutathione