Application of endocrine disruptor screening program fish short‐term reproduction assay: Reproduction and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus) exposed to Bermuda pond sediment

Abstract

A modified tier 1 Endocrine Disruptor Screening Program (EDSP) 21-d fish short-term reproduction assay (FSTRA) was used to evaluate the effects of sediment exposure from freshwater and brackish ponds in Bermuda on reproductive fecundity and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus). Reproductively active male and female fish were exposed to control sediment and sediment from 2 freshwater ponds (fathead minnow) and 2 marine ponds (killifish) contaminated with polyaromatic hydrocarbons and metals via flow-through exposure for 21 d. Reproductive fecundity was monitored daily. At termination, the status of the reproductive endocrine system was assessed by the gonadosomatic index, gonadal histology, plasma steroids (estrogen [E2], testosterone [T], and 11-ketotestosterone [11-KT]), steroidogenic enzymes (aromatase and combined 3β/17β -hydroxysteroid dehydrogenase [3β/17β-HSD]), and plasma vitellogenin (VTG). Decreased reproductive fecundity, lower male body weight, and altered endocrinological measures of reproductive status were observed in both species. Higher plasma T levels in female minnows and 11-KT levels in both male and female minnows and female killifish exposed to freshwater and brackish sediments, respectively. Decreased female E2 and VTG levels and gonadal cytochrome P19 (aromatase) activity were also found in sediment exposed females from both species. No effect on female 3β/17β-HSD activity was found in either species. The FSTRA provided a robust model capable of modification to evaluate reproductive effects of sediment exposure in fish.

Splenic immunotoxicity in developing cane toads (Rhinella marina) from Bermuda

“…Developmental deformities have also been identified in endemic killifish ( Fundulus bermudae ) , mosquitofish ( Gambusia affinis ) , and diamondback terrapins in Bermuda. More recently, Fort et al report reproduction and endocrine dysfunction in surrogate fish, fathead minnow ( Pimephales promelas ) and killifish ( Fundulus heteroclitus ), exposed to freshwater and marine sediment from Bermuda. In an effort to determine the role of metals and PAHs in the sediments from Bermuda on developmental, reproductive, endocrine, and immune processes in developing R. marina , a sediment spiking study was performed (D.J.…”

“…Gonadal abnormalities observed in adult toads from several sites suggested that endocrine‐disrupting chemicals may have affected the process of gonad differentiation in these animals . Furthermore, sediments from Cloverdale and Warwick Ponds were shown to impair reproduction and affect steroidogenesis in fathead minnows . Steroidogenesis in larval toads inhabiting the same ponds was similarly affected (D.J.…”