Chronic retene exposure causes sustained induction of CYP1A activity and protein in rainbow trout (Oncorhynchus mykiss)

• Published in: Environmental toxicology and chemistry Vol. 17; no. 11; pp. 2347 - 2353
• Main Authors: Fragoso, N.M. (Queen's University, Kingston, Ontario, Canada.), Parrott, J.L, Hahn, M.E, Hodson, P.V
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Periodicals, Inc 01.11.1998; SETAC
• Subjects: Agnatha. Pisces; AGUAS RESIDUALES; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; CITOCROMO P450; CYTOCHROME P450; Cytochrome P4501A; EAU USEE; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; ELABORACION DE PULPA; Ethoxyresorufin-O-deethylase; Fundamental and applied biological sciences. Psychology; Induction; ONCORHYNCHUS MYKISS; POLLUTION DE L'EAU; POLUCION DEL AGUA; Pulp mill effluent; PULPING; REDUCTION EN PATE; Retene; TOXICIDAD; TOXICITE; TOXICITY; WASTEWATER; WATER POLLUTION; Salmonidae; Unspecific monooxygenase; Enzyme; Toxicity; Cytochrome P450; Paper mill; Exposure; Oncorhynchus mykiss; Protein; Freshwater environment; Pollutant; Vertebrata; Chronic; Enzymatic activity; Organochlorine compounds; Pisces; Water pollution; Oxidoreductases; Effluent
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.5620171127

The removal of persistent chlorinated organic compounds from pulp mill effluents has not eliminated mixed function oxygenase (MFO) induction by these effluents. Therefore, continuous MFO induction downstream of pulp mills may be due to exposure to more labile compounds, such as retene (an alkyl-substituted phenanthrene), which typically cause transient induction after a single brief exposure. Because fish are exposed continuously to pulp mill effluents, we have tested, and rejected, the null hypothesis that continuous exposure of fish to retene does not cause sustained MFO induction. Rainbow trout exposed continuously to retene, a component of some pulp mill effluents and sediments downstream of pulp mills, showed concentration-dependent increases in hepatic ethoxyresorufin-O-deethylase (EROD) activity. The increase in EROD activity was sustained over 32 d of continuous exposure, but it diminished to background levels within 4 d after transfer to clean water. The enzymatic response was confirmed by measuring changes in the content of immunodetectable cytochrome P4501A (CYP1A) protein. These data support a role for labile, nonhalogenated compounds in chronic effects of pulp mill effluents on fish