Endocrine-disrupting effects of cattle feedlot effluent on an aquatic sentinel species, the fathead minnow.

Abstract

Over the last decade, research has examined the endocrine-disrupting action of various environmental pollutants, including hormones, pharmaceuticals, and surfactants, in sewage treatment plant effluent. Responding to the growth of concentrated animal feeding operations (CAFOs) and the pollutants present in their wastewater (e.g., nutrients, pharmaceuticals, and hormones), the U.S. Environmental Protection Agency developed a new rule that tightens the regulation of CAFOs. In this study, we collected wild fathead minnows (Pimephales promelas) exposed to feedlot effluent (FLE) and observed significant alterations in their reproductive biology. Male fish were demasculinized (having lower testicular testosterone synthesis, altered head morphometrics, and smaller testis size). Defeminization of females, as evidenced by a decreased estrogen:androgen ratio of in vitro steroid hormone synthesis, was also documented. We did not observe characteristics in either male or female fish indicative of exposure to environmental estrogens. Using cells transfected with the human androgen receptor, we detected potent androgenic responses from the FLE. Taken

Climate change and pollution speed declines in zebrafish populations

“…Some of these chemicals have been shown to alter sexual programming and reduce reproductive fitness in wild fish at environmentally relevant exposure concentrations (31,52,53). Additive effects have been shown for EDCs acting as estrogen receptor agonists (54), but less consideration has been given to the combined effects of exposure to EDCs with other modes of action, including modulators of other steroid hormone receptors (e.g., androgen receptor agonists or antagonists) and disruptors of hormone synthesis and metabolism.…”

Occurrence and fate of androgens, estrogens, glucocorticoids and progestagens in two different types of municipal wastewater treatment plants

“…18 Previous studies also reported that there is a connection between exposure of androgens and masculinization of fish. 48,49 Since there have been no reported PNEC values for androgens, glucocorticoids and progestagens, proper risk assessment could not be made. Therefore, control measures should be applied to further remove these steroids in the final effluents in order to reduce potential risks to aquatic organisms.…”

Integrated multi-omics analyses reveal the biochemical mechanisms and phylogenetic relevance of anaerobic androgen biodegradation in the environment

“…The increasing number of reports on intersex organisms found in global aquatic ecosystems has raised concerns regarding the occurrence and persistence of steroid hormones in the environment (Safe, 2004;Wise et al, 2011). Several studies have reported the masculinization of freshwater wildlife exposed to androgens in polluted rivers (Howell et al, 1980;Bortone et al, 1989;Parks et al, 2001;Orlando et al, 2004). Furthermore, steroids were identified as pheromones and adversely affect fish behavior even at extremely low concentrations (Kolodziej et al, 2003).…”