Reproductive, physiological, and biochemical responses in juvenile female rainbow trout (Oncorhynchus mykiss) exposed to sediment from pulp and paper mill industrial discharge areas.
Four pulp and paper mills discharge their effluents in the same section of the Biobio River in central southern Chile. Pulp mill effluents are a very complex mixture with characteristics that depend on the type of raw material, the process technology, and the effluent treatment. To investigate the effect of pulp mill effluent discharges, immature Oncorhynchus mykiss were exposed to river sediments in the laboratory for 29 d. Three sampling areas were defined in a spatial gradient in the river: Preimpact, impact, and postimpact zones relative to the pulp and paper mill discharge areas. Ethoxyresorufin-O-deethylase activities were significantly higher in fish exposed to impact and postimpact sediments when compared to those exposed to preimpact sediments, and higher levels of vitellogenin were observed in the plasma of female fish exposed to impact and postimpact sediments. Histological analysis of the gonadal tissue showed an induction of gonadal maturation in fish exposed to sediment coming from the impact and postimpact zones (oocytes in a vitellogenic state). No site differences were observed in erythrocytes, although differences were noted in the leukocytes in the exposure areas. Finally, the biomarker approach showed evidence that the sediment associated with pulp mill effluent discharges produces some effects in fish under laboratory conditions.
Orrego
Rodrigo
R
Aquatic Systems Research Unit, EULA-Chile Environmental Sciences Centre, University of Concepción, P.O. Box 160-C, Concepción, Chile. luorrego@udec.cl
Moraga-Cid
Gustavo
G
González
Margarita
M
Barra
Ricardo
R
Valenzuela
Ariel
A
Burgos
Abed
A
Gavilán
Juan F
JF
D000818:Animals; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D005260:Female; D006066:Gonads / Q000187:drug effects; D007220:Industrial Waste; D008297:Male; D017686:Oncorhynchus mykiss / Q000378:metabolism / Q000502:physiology*; D012098:Reproduction / Q000187:drug effects*; D013783:Textile Industry; D014819:Vitellogenins / Q000097:blood; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D007220:Industrial Waste; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D019363:Cytochrome P-450 CYP1A1