Reversibility of endocrine disruption in zebrafish (Danio rerio) after discontinued exposure to the estrogen 17α-ethinylestradiol

Ecotoxic pharmaceuticals, personal care products, and other emerging contaminants: A review of environmental, receptor-mediated, developmental, and epigenetic toxicity with discussion of proposed toxicity to humans

“…Here gonad immaturity was demonstrated at 3-10ng/L at 60dph in females and 1-10ng/L in males, a significant reduction in body length was shown at EE2 exposure levels between 3-10ng/L, and a female biased gender ratio (10% male where control was 61% male) at 3ng/L and an exclusively female population at 10ng/L sampled 60dph (Baumann et al 2014). Exposing biologically disrupted fish to a 40 day EE2-free so-called 'clean recovery' period, all of the observed disruption significantly diminished or returned to levels similar to the control except reduced body length in fish exposed to 10ng/L EE2 and the body weight of fish exposed to only 1ng/L EE2 which was significantly increased (Baumann et al 2014). …”

“…The scientific community has at large acknowledged that such contaminants are able to exert disruptive effects across multi trophic levels in the environment. Numerous biological complications have been studied in both aquatic and terrestrial organisms as a result of trace and ultra-trace level PPCP and EC exposure (e.g., Parrott and Blunt 2005;Baquero et al 2008;Vajda et al 2011;Hu et al 2012;Baumann et al 2014;Reyhanian Caspillo et al 2014). It is suggested that humans are no exception to this understanding.…”

“…Receptor-mediated toxicology is suggested to occur at contaminant concentrations from upper pg/L to very low µg/L (often less than 10 ng/L), much lower than regulatory testing limits (Welshons et al 2003;Baumann et al 2014;Reyhanian Caspillo et al 2014).…”

“…. Such manipulations are suggested to initiate at extremely low concentrations (suggested as low as parts per quadrillion) as hormonal receptors, such as the highly conserved estrogen receptor (ER), function with extraordinary affinity (Welshons et al 2003;Baumann et al 2014;Prins et al 2014;Reyhanian Caspillo et al 2014).…”

“…Exposing zebra fish (Danio Rerio) to 0.1-10ng/L EE2 from approximately 4hr to 60 days post-hatch (dph) followed by 40 days in a clean environment, Baumann et al (2014) assess the occurrence and reversibility of disruption in gonad maturity, vitellogenin (VTG) expression, gender ratio, body size and weight. Here gonad immaturity was demonstrated at 3-10ng/L at 60dph in females and 1-10ng/L in males, a significant reduction in body length was shown at EE2 exposure levels between 3-10ng/L, and a female biased gender ratio (10% male where control was 61% male) at 3ng/L and an exclusively female population at 10ng/L sampled 60dph (Baumann et al 2014).…”