Effects of ECF-Kraft pulp mill effluent treated with fungi (Rhizopus oryzae) on reproductive steroids and liver CYP1A of exposed goldfish (Carassius auratus)

• Published in: Ecotoxicology (London) Vol. 18; no. 8; pp. 1011 - 1017
• Main Authors: Diniz, M. S., Peres, I., Castro, L., Freitas, A. C., Rocha-Santos, T. A. P., Costa, P. M., Pereira, R., Duarte, A. C.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.11.2009; Springer Nature B.V
• Subjects: Animals; Biomarkers; Carassius auratus; Cytochrome P-450 CYP1A1 - drug effects; Cytochrome P-450 CYP1A1 - metabolism; Earth and Environmental Science; Ecology; Ecotoxicology; Effluent treatment; Endocrine disruptors; Environment; Environmental Management; Enzyme Induction - drug effects; Female; Fish physiology; Freshwater; Goldfish - metabolism; Gonadal Steroid Hormones - metabolism; Gonads; Histopathology; Industrial Waste - adverse effects; Industrial wastewater; Liver; Liver - drug effects; Liver - metabolism; Male; Organic compounds; Physiology; Pulp wastes; Rhizopus - metabolism; Rhizopus oryzae; Steroids; Wastewater treatment; Water Pollutants, Chemical - toxicity; Biomarkers; Histopathology; Toxicity; BKME
• ISSN: 0963-9292; 1573-3017
• DOI: 10.1007/s10646-009-0392-4

The toxicity of bleached Kraft pulp mill effluents (BKME) is usually attributed to chemical compounds which are produced and released throughout various stages of pulp and paper production. The main objective of the present work was to detect sub-lethal responses of goldfish ( Carassius auratus ) to secondary treated BKME which was treated with Rhizopus oryzae . A total of 96 carps ( C. auratus ; 11 ± 3 g) were exposed to different concentrations of the post-treated effluent (0, 1, 10, 25, 50, and 100%), in 28 days semi-static tests. Several biomarkers were then evaluated to assess the toxicological effects: induction of CYP1A (metabolic processes of organic compounds in liver), change in steroid profiles (11-Ketotestosterone, 17β-estradiol), histopathology of liver and gonads and somatic indices (GSI, HSI) for endocrine disruption and other physiological disturbances. The most significant results show an induction of CYP1A in both sexes and a decrease of 17β-estradiol concentrations in females. Histopathological changes such as liver tissue degeneration were observed in fish exposed to 50 and 100% of the BKME. Although the BKME was biologically treated there are some chemical compounds in the effluent that are capable to affect fish physiology, however, a clear evidence for endocrine disruption was not found.