The Challenge Presented by Progestins in Ecotoxicological Research: A Critical Review.

Around twenty progestins (also called gestagens, progestogens or progestagens) are used today in assisting a range of medical conditions from endometrial cancer to uterine bleeding and as an important component of oral contraception. These progestins can bind to a wide range of receptors including progestin, estrogen, androgen, glucocorticoid, mineralocorticoid receptor, as well as sex hormone and corticosteroid binding globulins. It appear that only five of these (four synthetic and one natural) progestins have so far been studied in sewage effluent and surface waters. Analysis has reported values as either non-detects or low ng/L in rivers. Seven of the progestins have been examined for their effects on aquatic vertebrates (fish and frogs). The greatest concern is associated with levonorgestrel, norethisterone and gestodene and their ability to reduce egg production in fish at levels of 0.8-1.0 ng/L. The lack of environmental measurements, and some of the contradictions in existing values, however, hampers our ability to make a risk assessment. Only a few of ng/L of ethynodiol diacetate and desogestrel in water would be needed for fish to receive a human therapeutic dose for these progestins according to modelled bioconcentration factors. But for the other synthetic progestins levels would need to reach tens or hundreds of ng/L to achieve a therapeutic dose. Nevertheless, the wide range of compounds, diverse receptor targets and the effect on fish reproduction at sub ng/L levels should prompt further research. The ability to impair female reproduction at very low concentrations make the progestins arguably the most important pharmaceutical group of concern after ethinylestradiol.
SCOPUS: re.j
info:eu-repo/semantics/published