title: Do suspended sediments modulate the effects of octylphenol on rainbow trout?
abstract: A system was devised which allows particles to remain in suspension in a conventional 60 L aquarium without undue disturbance to resident fish. Using this system, juvenile rainbow trout were exposed for one week to 4-tert-octylphenol (OP, 10-1000 microg/L) with or without the presence of suspended sediments (10-20mg/L of natural suspended sediments from the River Calder, UK). About 8% of the added OP partitioned to the solid phase. Vitellogenin levels were determined in the plasma of the exposed rainbow trout and showed a dose-dependent increase with regards to OP exposure concentration. Considerable variation in the vitellogenin response was observed between separate runs with the same OP concentration. There was no statistically significant (at P < 0.05) difference in plasma VTG levels between the OP treatments with or without suspended sediments. This suggests that the dissolved concentration is the key factor and natural suspended sediment neither protects against, nor exacerbates, the endocrine disrupting effect of OP on fish.
authors.affiliation: Centre for Ecology and Hydrology (CEH), Maclean Building, Benson Lane, Crowmarsh Gifford, Wallingford, Oxfordshire OX108BB, UK. mdj@ceh.ac.uk
authors.forename: Monika D
authors.initials: MD
authors.lastname: Jürgens
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Johnson
authors.forename: Tom G
authors.initials: TG
authors.lastname: Pottinger
authors.forename: John P
authors.initials: JP
authors.lastname: Sumpter
mesh_terms: D000818:Animals; D005260:Female; D019015:Geologic Sediments / Q000737:chemistry*; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D017686:Oncorhynchus mykiss / Q000097:blood / Q000378:metabolism*; D010636:Phenols / Q000032:analysis / Q000633:toxicity*; D045483:Rivers / Q000737:chemistry; D013535:Suspensions; D018675:Toxicity Tests; D006113:United Kingdom; D014819:Vitellogenins / Q000097:blood
chemical_list: D010636:Phenols; D013535:Suspensions; D014819:Vitellogenins; C474055:octylphenol; D006854:Hydrocortisone