Abstract
Estrogenic endocrine disrupting chemicals (EEDC) have been suspected to impact offspring in a transgenerational manner via modifications of the germline epigenome in the directly exposed generations. A holistic assessment of the concentration/ exposure duration-response, threshold level, and critical exposure windows (parental gametogenesis and embryogenesis) for the transgenerational evaluation of reproduction and immune compromise concomitantly will inform the overall EEDC exposure risk. We conducted a multigenerational study using the environmental estrogen, 17α-ethinylestradiol (EE2), and the marine laboratory model fish Oryzias melastigma (adult, F0) and their offspring (F1-F4) to identify transgenerationally altered offspring generations and phenotype persistence. Three exposure scenarios were used: short parental exposure, long parental exposure, and a combined parental and embryonic exposure using two concentrations of EE2 (33ng/L, 113ng/L). The reproductive fitness of fish was evaluated by assessing fecundity, fertilization rate, hatching success, and sex ratio. Immune competence was assessed in adults via a host-resistance assay. EE2 exposure during both parental gametogenesis and embryogenesis was found to induce concentration/ exposure duration-dependent transgenerational reproductive effects in the unexposed F4 offspring. Furthermore, embryonic exposure to 113 ng/L EE2 induced feminization of the directly exposed F1 generation, followed by subsequent masculinization of the F2 and F3 generations. A sex difference was found in the transgenerationally impaired reproductive output with F4 females being sensitive to the lowest concentration of EE2 (33 ng/L) upon long-term ancestral parent exposure (21 days). Conversely, F4 males were affected by ancestral embryonic EE2 exposure. No definitive transgenerational impacts on immune competence were identified in male or female offspring. In combination, these results indicate that EEDCs can be transgenerational toxicants that may negatively impact the reproductive success and population sustainability of fish populations.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
