Synthetic Progestins in Waste and Surface Waters: Concentrations, Impacts and Ecological Risk

Abstract

Synthetic progestins (PGs) are a large family of hormones used in continuously growing amounts in human and animal contraception and medicinal therapies. Because wastewater treatment plants (WWTPs) are unable to eradicate PGs after excretion, they are discharged into aquatic systems, where they can also be regenerated from conjugated PG metabolites. This review summarises the concentrations of 12 PGs in waters from 2015 to 2021. The selected PGs were considered of particular interest due to their wide use, activity, and hormonal derivation (from testosterone, progesterone, and spirolactone). We concluded that PGs had been analysed in WWTPs influents and effluents and, to a lesser extent, in other matrices, including surface waters, where their concentrations range from ng/L to a few µg/L. Because of their high affinity for cell hormone receptors, PGs are endocrine disruptor compounds that may alter the reproductive fitness and development of biota. This review focused on their biological effects in fish, which are the most used aquatic model organisms to qualify the impacts of PGs, highlighting the risks that environmental concentrations pose to their health, fecundity, and fertility. It is concluded that PGs research should be expanded because of the still limited data on their environmental concentrations and effects.

Keywords: EDCs; drospirenone; estranes; gestagens; gonanes; norpregnanes; pregnanes; risk assessment.

Figure 1

Locations in which studies on the levels of the synthetic PGs considered in this article were conducted in the aquatic environment from 2015 to 2021 (map generated from https://mapchart.net/world.html, accessed on 27 December 2021).

Figure 2

Data are expressed in boxplots with the minimum, median, maximum, average (+), and interquartile range Q1–Q3. Dots represent average individual values measured in surface waters (S_w), WWTP influent (WWTP_i) and WWTP effluents (WWTP_e) around the world concerning PGs derivates from (A) Testosterone (n = 42 S_w, n = 42 WWTP_i, and n = 62 WWTP_e), (B) Progesterone (n = 23 S_w, n = 22 WWTP_i, and n = 29 WWTP_e), (C) Spirolactone (n = 7 S_w, n = 7 WWTP_i, and n = 9 WWTP_e), (D) all PGs as a whole (n = 72 S_w, n = 71 WWTP_i and n = 100 WWTP_e), (E) all PGs referred in a previous review (n = 4) [7].

Figure 3

Sources and pathways for the occurrence of progestins in the environment. The distributions of PGs were based on Besse and Garric (2009) [51].

Figure 4

Routes of entry, circulation, major places of action, and the fate of progestins such as pregnanes, estranes, gonanes, spironolactone derivatives, and other EDCs.