Estrogenic effect of the phytoestrogen biochanin A in zebrafish, Danio rerio, and brown trout, Salmo trutta

Endocrine‐disrupting effect of the ultraviolet filter benzophenone‐3 in zebrafish, Danio rerio

“…The lack of induction of vitellogenin synthesis in the present study's TG 234 experiment (p > 0.25) could suggest that vitellogenin induction after exposure to BP-3 is slightly more sensitive in the adult stage than in the juvenile stage. This higher sensitivity of vitellogenin induction after exposure to estrogenic substances in adults compared with juveniles has previously been observed in fish [29,[33][34][35] and has been ascribed to immaturities in the juveniles leading to differences in expression of the estrogen receptor [34] or differences in the biotransformation reaction rates of the substances [35]. In the present study, juveniles may differ from adults in their metabolism of BP-3.…”

“…This effect was manifested as a monotone dosedependent skewing of the phenotypic sex ratio toward less male and more female zebrafish, with a NOEC of 191 mg/L and a LOEC 388 mg/L BP/3 (measured concentrations). Sexual differentiation in zebrafish is very sensitive to exposure to exogenous hormones, and altered sex ratios are inducible with estrogenic substances [24,29,30,31], androgens [25], and aromatase inhibitors [21,32]. The change in sex ratio toward more phenotypically female and less phenotypically male zebrafish observed in the present study indicates an overall estrogenic or an antiandrogenic activity of BP-3.…”

The response of thyroid hormones, biochemical and enzymological biomarkers to pyrene exposure in common carp (Cyprinus carpio)

“…If a significant difference was observed, only the solvent group was used as the control. When the solvent and water control groups did not show any significant differences, the data from two controls were pooled (Holbech et al, 2013;Shirdel and Kalbassi, 2016). To compare the pyrene treatments and the control group, one-way analysis of variance (ANOVA) and the Dunnett test (parametric) or Mann-Whitney U test (nonparametric) were performed.…”

Vitellogenin concentrations in feral Danish brown trout have decreased: An effect of improved sewage treatment in rural areas?

“…Release of smolt cannot explain the decline between 2004 and 2010 to 2016 because vitellogenin concentrations of male smolt from the hatchery were determined between 2004 to 2010 and remained in the range 10 to 150 ng mL À1 (Holbech et al 2013;Knudsen et al 2011), which resemble the values obtained in the field surveys between 2010 and 2016. Since 2001, 1-yr brown trout (smolt), reared at a local hatchery, have been released in stream mouths during spring to support the natural populations, but artificial genetic mixing is prevented by release of smolt of parent fish originating from the same stream.…”

“…Thus the fish populations consist of both feral and released fish but with similar genetic backgrounds. Release of smolt cannot explain the decline between 2004 and 2010 to 2016 because vitellogenin concentrations of male smolt from the hatchery were determined between 2004 to 2010 and remained in the range 10 to 150 ng mL À1 (Holbech et al 2013;Knudsen et al 2011), which resemble the values obtained in the field surveys between 2010 and 2016. Furthermore, because sampling occurred in the autumn, any difference in vitellogenin concentration between reared and feral trout would be eliminated after a few months.…”