Intersex and liver alterations induced by long‐term sublethal exposure to 17α‐ethinylestradiol in adult male Cnesterodon decemmaculatus (Pisces: Poeciliidae)

Abstract

The aim of the present study was to assess the responses of the gonopodium morphology and the gonadal and liver histology of adult male Cnesterodon decemmaculatus to sublethal long-term exposure concentrations of 17α-ethinylestradiol (EE2). Two experiments were conducted exposing the fish to waterborne concentrations of EE2 ranging from 20 ng/L to 200 ng/L for 8 wk, 12 wk, and 16 wk. Intersex gonads were observed after 8 wk and 16 wk in fish exposed to 200 ng EE2/L and 100 ng EE2/L, respectively. Oocytes' development from testis germ cells and replacement of the efferent duct periodic acid-Schiff-positive secretion surrounding spermatozeugmata by parenchymal tissue and duct structure alterations were the major observed changes in the gonads. In contrast, no response was observed in the gonopodium morphology. Liver histology was also altered, showing increasing steatosis, single-cell necrosis to generalized necrosis, and disruption of acinar organization from 100 ng EE2/L to 200 ng EE2/L. In summary, the present results showed that although EE2 was not able to alter the morphology of a developed gonopodium, it was capable of inducing development of testicular oocytes in adult male C. decemmaculatus at environmentally relevant concentrations. Thus, externally normal but intersex C. decemmaculatus males would be expected in the wastewater-receiving streams that the species inhabits. According to the literature, the present study would be the first indicating estrogen-induced intersex in adult male poeciliid. Environ Toxicol Chem 2017;36:1738-1745. © 2016 SETAC.

A Reduced Model for Bioconcentration and Biotransformation of Neutral Organic Compounds in Midge

“…A major limitation of the developed midge BCF model is its restricted application to neutral organic compounds. A logical next step is to explore how well the same reduced toxicokinetic framework may be extended toward ionizable organic compounds, which have been gaining attention in recent years for their ubiquity and potent ecotoxicological effects on aquatic organisms (Parolini et al 2017; Thorngren et al 2017; Young et al 2017).…”

Bioconcentration model for non‐ionic, polar, and ionizable organic compounds in amphipod

“…With growing scientific and public concern, PIOCs have emerged as contaminants of major concern (Boxall et al ). They include many pharmaceuticals, pesticides, and industrial chemicals with potent ecotoxicological effects (de Brito Rodrigues et al ; Parolini et al ; Thorngren et al ; Villeneuve et al ; Young et al ). Aquatic organisms are particularly vulnerable to their presence because a number of PIOCs are detected in different water bodies and can persist through harsh treatment processes (Maruya et al ; Cantwell et al ; Sadaria et al ).…”

Effect of exposure to palm oil mill effluent on reproductive impairment of male Nile Tilapia (Oreochromis niloticus, Linnaeus 1758)

“…The lower value of GSI is thought to occur due to the disturbance development of male fish gonads during spermatogenesis. Several studies also reported a decrease in the value of GSI in male fish due to exposure to various types of pollutants, for instance, mercury, cadmium, and 17αethinylestradiol [20,21,22].…”