Natural estrogens in surface waters of a catchment with intensive livestock farming in Switzerland

Sample Preparation Techniques for Growth-Promoting Agents in Various Mammalian Specimen Preceding MS-Analytics

The misuse of growth-promoting drugs such as beta-2 agonists and steroids is a known problem in farming and sports competitions. Prior to the analysis of biological samples via liquid chromatography (LC)-mass spectrometry (MS) or gas chromatography (GC)-MS, sufficient sample preparation is required to reliably identify or determine the residues of drugs. In practice, broad screening methods are often used to save time and analyze as many compounds as possible. This review was conceptualized to analyze the literature from 2018 until October 2023 for sample preparation procedures applied to animal specimens before LC- or GC-MS analysis. The animals were either used in farming or sports. In the present review, solid phase extraction (SPE) was observed as the dominant sample clean-up technique for beta-2 agonists and steroids, followed by protein precipitation. For the extraction of beta-2 agonists, mixed-mode cation exchanger-based SPE phases were preferably applied, while for the steroids, various types of SPE materials were reported. Furthermore, dispersive SPE-based QuEChERs were utilized. Combinatory use of SPE and liquid-liquid extraction (LLE) was observed to cover further drug classes in addition to beta-2 agonists in broader screening methods.

Endocrine Disruption Is Reduced but Still Widespread in Wild Roach (Rutilus rutilus) Living in English Rivers

Endocrine disruption of wild fish, primarily resulting in the feminization of males, has been reported in English river sites for several decades. Estrogenic activity emanating from wastewater treatment works (WwTW) has been conclusively demonstrated to be the main driver of these feminized phenotypes. Here, we revisit 10 English river sites previously surveyed in the late 1990s and early 2000s to assess how the frequency and severity of feminization now compare with the historical surveys. In the contemporary assessment, 60% of the sites revisited still showed endocrine disruption at the tissue organization level (oocytes present in otherwise male gonads; intersex) and 90% of sites had average male plasma vitellogenin concentrations (female-specific yolk protein; a sensitive biomarker of estrogen exposure) above natural baseline levels. In contrast to the historic surveys, none of the males sampled in the contemporary survey had ovarian cavities. At one of the larger WwTW, improvements to treatment technology may have driven a significant reduction in intersex induction, whereas at several of the smaller WwTW sites, the frequencies of feminization did not differ from those observed in the late 1990s. In conclusion, we show that although the severity of feminization is now reduced at many of the revisited sites, endocrine-disrupting chemicals are still impacting wild fish living downstream of WwTW in England.

A robust multi-residue method for the monitoring of 25 endocrine disruptors at ultra-trace levels in surface waters by SPE-LC-MS/MS

Estrogenic endocrine disruptors are one of the biggest ecotoxicological threats in water that pose a significant ecological burden and health-risk for humans due to their high biological activity and proven additive effects. Therefore, we have developed and validated the most comprehensive and ultra-sensitive analytical method published to date, for reliable quantification of 25 high-risk endocrine disruptors at their ecologically relevant concentrations: naturally excreted hormones (estradiol, estrone, estriol, testosterone, corticosterone, and progesterone), synthetic hormones used for contraception and menopausal symptoms (ethinylestradiol, drospirenone, chlormadinone acetate, norgestrel, gestodene, tibolone, norethindrone, dienogest, and cyproterone) and bisphenols (BPS, BPA, BPF, BPE, BPAF, BPB, BPC, and BPZ). It is based on a solid-phase extraction of water samples, followed by a robust dansyl chloride derivatization with detection by liquid chromatography-tandem mass spectrometry with a single sample preparation and two analytical methods using the same analytical column and mobile phases. The achieved limits of quantitation are in the sub-ng L^-1 range, and detection limits as low as 0.02 ng L^-1, meeting the newest proposal for environmental quality standards (EQS) by the EU water framework directive for estradiol and ethinylestradiol. The method was extensively validated and applied to seven representative Slovenian water samples, where we detected 21 out of 25 analytes; 13 were quantified in at least one sample. Estrone and progesterone were quantified in all samples, reaching levels up to 50 ng L^-1; ethinylestradiol was higher than the current EQS (0.035 ng L^-1) in three samples, and estradiol was above its EQS (0.4 ng L^-1) in one sample, proving the method's applicability and the necessity for monitoring these pollutants.

Estrogen pollution of the European aquatic environment: A critical review

Among the plethora of chemicals released into the environment, much attention is paid to endocrine disrupting compounds (EDCs). Natural estrogens, such as estrone (E1), 17β-estradiol (E2), estriol (E3) are excreted by humans as well as animals, and can enter the environment as a result of discharging domestic sewage and animal waste. These compounds can cause deleterious effects such as feminization, infertility and hermaphroditism in organisms that inhabit water bodies. This study provides an overview of the level of estrogen exposures in surface waters, groundwater and river sediments in European countries. The conducted review shows that estrogen concentrations were within the range of 0.1 ng L - 10 ng /L in the majority of the tested environmental samples. However, the authors of the study point out that there are still many unexplored areas and a limited amount of data that mainly concerns Eastern European countries. The study also analysed the factors that influence the increased emissions of estrogens to the environment, which may be helpful for identifying particularly polluted areas.

Natural estrogen emissions to subsurface tile drains from experimental grassland fields in Switzerland after application of livestock slurries and free compounds

Natural estrogens are present in high concentrations in livestock slurries, which are often applied to agricultural fields in large quantities. As such, the export of slurry-derived natural estrogens from tile-drained fields is a potential source for estrogenic pollution in surface waters. Yet despite the abundance of tile-drained fields in Central Europe, export of natural estrogens from agricultural fields receiving livestock slurries is rarely studied in this region. In an effort to fill this knowledge gap, here we applied natural estrogens to Swiss experimental fields in the form of cattle slurry, pig slurry or dissolved in water, and quantified them in flow-proportionally collected drainage water over 18 months. After pig and cattle slurry applications, concentration maxima in drainage water of 73, 8, 37, and 60 ng L^-1 for 17α-estradiol (E2α), 17β-estradiol (E2β), estrone (E1), and estriol (E3), respectively, were observed shortly after rain events. The exported fractions of individual natural estrogens to tile drains were on average 0.26% (ranging from 0.08 to 0.41%) after cattle, and 0.18% (0.03-0.40%) after pig slurry applications. Such numbers were higher than expected from the leaching potential based on substance properties, and comparable to those of more mobile micropollutants previously studied on the same fields. Natural estrogens were mainly exported to tile drains through preferential flow. Exported fractions were lower when applied in aqueous solution than when applied in slurry, pointing to particle-facilitated transport to tile drains when applied in slurry. In Switzerland, the estimated 6.3, 0.6, 7.4, and 7.7 g of E2α, E2β, E1, and E3, respectively, exported through the tile-drained agricultural area per year contribute little to the total natural estrogen load received by surface waters. However, after slurry applications in highly drained catchments, natural estrogen emissions to tile drains can cause short term (i.e. less than 1 week) estrogenic exposure in nearby streams.