Fathead minnow response to broad‐range exposure of β‐sitosterol concentrations during life‐cycle testing

• Published in: Environmental toxicology and chemistry Vol. 33; no. 2; pp. 458 - 467
• Main Authors: Flinders, Camille A, Streblow, William R, Philbeck, Raymond E, Cook, Diana L, Campbell, David E, Brown‐Peterson, Nancy J, Gross, Timothy S
• Format: Journal Article
• Language: English
• Published: Pensacola, FL Blackwell Publishing Ltd 01.02.2014; SETAC
• Subjects: acetone; Agnatha. Pisces; animal growth; Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Cyprinidae - physiology; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; egg production; estradiol; Ethynyl estradiol; Fathead minnow; fecundity; Female; Fertility - drug effects; fish; Freshwater; Fundamental and applied biological sciences. Psychology; Gonads - anatomy & histology; Gonads - drug effects; histology; Life Cycle Stages; Life-cycle assessment; Male; males; mortality; phytosterols; Pimephales promelas; pulp and paper mill effluents; Reproduction - drug effects; Sitosterols - toxicity; spawning; vitellogenin; Water Pollutants, Chemical - toxicity; β-Sitosterol; Steroid; β-Sitosterol; Toxicity; Ecobalance; Estrogen; Estradiol; Life-cycle assessment; Concentration measurement; Freshwater environment; Sitosterol; Pollutant; Vertebrata; Lifetime; Pisces; Environment impact; Phytosterol; Ethynyl estradiol; Fathead minnow; Pimephales promelas; Developmental stage; Sterol
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.2440

The β‐sitosterol concentration in pulp and paper mill effluents is typically greater than that of other phytosterols and has been shown to cause a variety of effects in fish. The authors exposed fathead minnow (Pimephales promelas) to low (22 ± 0.93 µg/L), medium‐low (70 ± 2.1 µg/L), medium‐high (237 ± 5.5 µg/L), and high (745 ± 16.2 µg/L) concentrations of β‐sitosterol as well as negative (water), positive (ethynyl estradiol, 16 ± 0.58 ng/L), and carrier (0.6 mL/L acetone) controls. Fish were monitored over a full life cycle for population‐level endpoints including growth and survival, reproductive endpoints (e.g. fecundity, sex steroids and vitellogenin, gonado‐/hepatosomatic indices, and gonad histology). No significant differences were seen in fish growth, mortality, or reproduction with β‐sitosterol exposure, although a trend for lower egg production in β‐sitosterol exposures relative to the water control may be related to the acetone carrier. All ethynyl estradiol–exposed fish were smaller, showed female characteristics, and did not spawn. Sex steroid and vitellogenin were highly variable with no detectable treatment‐related differences. Gonadal tissue showed no β‐sitosterol–related differences in reproductive development and spawning capability, although most ethynyl estradiol–exposed males had ovarian tissue and were not spawning‐capable. The results indicate that β‐sitosterol exposure had little apparent impact on fathead minnow survival, growth, and reproduction even at concentrations >10 times that of typical effluents, although small sample size and variability precluded fully evaluating treatment responses on sex steroids and vitellogenin. Environ Toxicol Chem 2014;33:458–467. © 2013 SETAC