Detection and quantification of metastable photoproducts of trenbolone and altrenogest using liquid chromatography–tandem mass spectrometry

Biotransformation of cyproterone acetate, drospirenone, and megestrol acetate in agricultural soils: Kinetics, microbial community dynamics, transformation products, and mechanisms

The occurrence of biologically active synthetic progestins in agricultural soils is of growing concern due to their potential to disrupt the endocrine function of aquatic fish in nearby surface waters. This study investigated the biotransformation outcomes of cyproterone acetate (CPA), drospirenone (DRO), and megestrol acetate (MGA) in four agricultural soils. The biotransformation data were fitted to a first-order decay model (R2 = 0.93-0.99), with half-lives and first-order decay coefficients ranging from 76.2-217 h and 9.10 × 10-3-3.20 × 10-3 (h-1), respectively. Abundant biotransformation products (TPs) were generated during incubation, with the number and yields varying across the four soils. 1,2-Dehydrogenation was the main transformation pathway of DRO in the four soils (yields of 32.3-214 %). Similarly, 1,2-dehydrogenation was the most relevant transformation pathway of MGA in the four soils (yields of 21.8-417 %). C3 reduction was the major transformation pathway of CPA in soils B, C, and D (yields of 114-245 %). Hydrogenation (yield of 133 %) and hydroxylation (yield of 21.0 %) were the second major transformation pathway of CPA in soil B and C, respectively. In particular, several TPs exhibited progestogenic and antimineralocorticoid activity, as well as genotoxicity. The high-throughput sequencing indicated that interactions between microorganisms and soil properties may affect biotransformation. Spearman correlation and bidirectional network correlation analysis further revealed that soil properties can directly interfere with the soil sorption capacity for the progestins, thus affecting biotransformation. In particular, soil properties can also limit or promote biotransformation and the formation of TPs (i.e., biotransformation pathways) by affecting the relative abundances of relevant microorganisms. The results of this study indicate that the ecotoxicity of synthetic progestins and related TPs can vary across soils and that the assessment of environmental risks associated with these compounds requires special consideration of both soil properties and microbial communities.

Porphyrin-based metal-organic frameworks enhanced electrochemiluminescence (ECL) by overcoming aggregation-caused quenching: A new ECL emitter for the detection of trenbolone

The development of new electrochemiluminescence (ECL) luminophores has become a hot research topic in the field of ECL. Metal-organic frameworks (MOFs) are widely used in ECL sensors due to their excellent ECL performance, high porosity, and abundant surface functional groups. In the work, we developed a cerium-based organic backbone as an ECL luminophor using 5,10,15,20-tetrakis(4-carboxyphenyl)-porphyrin (TCPP) as organic ligand for the detection of trenbolone (TRE). Importantly, the Ce-MOFs can effectively prevent the self-aggregation and self-quenching of TCPP, so that the ECL signal is amplified. To further improve the conductivity and antigen loading capacity of the Ce-MOFs, platinum nanosheets (Pt NPs) were modified at its surface (Pt NPs@MOFs). The Au-ZnO with good biocompatibility is used as the substrate material to load that antibody through the Au-NH2. Based on the above strategy, we constructed a competitive immunosensor to achieve a highly sensitive detection of TRE. Under suitable circumstances, it was discovered that the ECL sensor had a linear relationship with the logarithm of the TRE concentration, with a limit of detection (LOD) of 3.61 fg/mL (S/N = 3). This work provides direction for the application of organic luminescent porphyrins and their derivatives in ECL sensors.

Biotransformation of Current-Use Progestin Dienogest and Drospirenone in Laboratory-Scale Activated Sludge Systems Forms High-Yield Products with Altered Endocrine Activity

Dienogest (DIE) and drospirenone (DRO) are two fourth-generation synthetic progestins widely used as oral contraceptives. Despite their increasing detection in wastewaters and surface waters, their fate during biological wastewater treatment is unclear. Here, we investigated DIE and DRO biotransformation with representative activated sludge batch incubations and identified relevant transformation products (TPs) using high-resolution mass spectrometry. DIE exhibited slow biotransformation (16-30 h half-life) and proceeded through a quantitative aromatic dehydrogenation to form TP 309 (molar yields of ∼55%), an aromatic TP ∼30% estrogenic as 17β-estradiol. DRO experienced more rapid biotransformation (<0.5 h half-life), and 1,2-dehydrogenation formed the major TP 364 (molar yields of ∼40%), an antimineralocorticoid drug candidate named as spirorenone. Lactone ring hydrolysis was another important biotransformation pathway for DRO (molar yields of ∼20%) and generated pharmacologically inactive TP 384. Other minor pathways for DIE and DRO included hydroxylation, methoxylation, and 3-keto and C4(5) double-bond hydrogenation; distinct bioactivities are plausible for such TPs, including antigestagenic activity, antigonadotropic activity, and pregnancy inhibition effects. Thus, biotransformation products of DIE and DRO during wastewater treatment should be considered in environmental assessments of synthetic progestins, especially certain TPs such as the estrogenic TP 309 of DIE and the antimineralocorticoid spirorenone (TP 364) of DRO.

Occurrence and distribution of natural and synthetic progestins, androgens, and estrogens in soils from agricultural production areas in China

The occurrence of biologically potent sex hormones in agricultural soils is of growing concern due to their ability to disrupt the endocrine systems of aquatic organisms after being transported to surface waters via runoff. This study, therefore, examined the large-scale occurrence of 34 natural and synthetic sex hormones (13 progestins, 16 androgens, and 5 estrogens) in soils from 7 provinces and 1 municipality in China. The target sex hormones were detected in 99.3% of the soil samples, indicating their widespread occurrence in most agricultural areas. Additionally, seven synthetic progestins were detected in soils for the first time. The total concentration of the 34 sex hormones (Σsex hormones) in the sampled soils ranged from below the method detection limit to 23.7 ng/g (mean of 4.72 ± 4.07 ng/g), with androgens and progestins being the most dominant hormone groups. Significant correlations were observed among the concentrations of Σestrogens, Σandrogens, and Σprogestins (r = 0.117-0.433, p < 0.001), suggesting similar sources of sex hormones. The mean concentration of Σsex hormones varied considerably across the selected provinces/municipality. Notably, the annual slaughter of poultry and swine (R² = 0.75-0.88), female population (R² = 0.57-0.58), and soil organic carbon content (R² = 0.20-0.55) in each province were significantly correlated with the concentrations or mean concentrations of Σsex hormones, Σestrogens, or Σprogestins. This finding implies that these parameters contributed to the occurrence and distribution of sex hormones in the studied soils. Finally, risk quotients for some sex hormones exceeded 0.01, indicating medium or high risks to agroecosystems. This study highlights the importance of designing an optimal manure fertilization strategy in order to mitigate the risks posed by sex hormones in agroecosystems.

Sorption and desorption of seven steroidal synthetic progestins in five agricultural soil-water systems

Manure fertilization and wastewater irrigation can introduce the biologically potent synthetic progestins into agricultural soils, causing endocrine disruption in organisms of nearby surface waters. Therefore, this study investigated the sorption and desorption potential of etonogestrel, medroxyprogesterone, gestodene, norgestrel, cyproterone acetate, levonorgestrel, and dienogest in five agricultural soil-water systems. Sorption data were well-described by the linear sorption model. In most batch systems, cyproterone acetate exhibited the highest affinities for soils, followed by etonogestrel, medroxyprogesterone, levonorgestrel, gestodene, norgestrel, and dienogest. The sorption magnitudes (logK_oc or logK_d) were significantly correlated with the progestin hydrophobicities (R² = 0.72-0.86, p < 0.05). The K_d values of the progestins were also significantly correlated with organic carbon content and pore volumes of the soils (R² = 0.68-0.98, p < 0.05). In addition, 0.5 M urea resulted in 3-19% decreases in K_d values of the progestins. Taken together, these data indicated that hydrophobic partitioning interaction, hydrogen bonding interaction, and pore filling were the sorption mechanisms for the progestins in soil-water systems. No significant desorption hysteresis was observed for the progestins, indicating that they can be readily desorbed under rainfall or irrigation events. Based on the sorption and desorption data, we estimated the dynamic transport of the progestins in conventional agricultural management systems, and predicted the concentrations of the progestins as a function of soil-sorbed concentration, water-soil ratio, and dilution factor of receiving waters. This study will improve the understanding of the risks posed by the progestins under field-scale hydrological conditions.

Sorption, transport, and transformation of natural and synthetic progestins in soil-water systems

Natural and synthetic progestins are emerging endocrine disruptors that can be transported from livestock farms and agricultural fields to receiving waters via surface runoff. The transformation of progestins during transport is expected to affect the efficiencies of runoff management systems. Therefore, this study explored the sorption, transport, and transformation of progesterone, norethisterone acetate, medroxyprogesterone acetate, cyproterone acetate, dydrogesterone, and norethisterone in agricultural soil-water systems. The sorption coefficients and retardation factors (R) were positively correlated with the progestin hydrophobicities, indicating that hydrophobic interactions dominated the sorption and transport processes. During transport, dydrogesterone and progesterone were transformed into 9-10 products. The breakthrough curves of the parents and products exhibited periodical patterns over extended times. Specifically, the R values of the parents and products were positively correlated with chromatographic retention times (hydrophobicities) when the products were generated before transport. In contrast, a negative correlation (R² = 0.75-0.88) was observed when products were successively generated during transport, indicating that the transformation kinetics changed the retardation of these solutes in the columns. These observations also demonstrated that the transport potential estimates based on traditional metrics of steroid hydrophobicity are not always accurate and that runoff management measures are less effective for metastable progestins.

Disruption of male mating strategies in a chemically compromised environment

A leading source of endocrine-disrupting chemicals (EDCs) in the environment is run-off of veterinary pharmaceuticals used in agriculture, including hormonal growth promotants (HGPs). Despite being banned in various countries, HGP use is still common in beef production around the world. The androgenic steroid 17β-trenbolone (17β-TB) is a HGP that commonly enters surface waters via livestock effluent run-off. Here, we used a flow-through system to expose wild-caught adult male guppies (Poecilia reticulata) to an environmentally realistic level of 17β-TB (average measured concentration = 2 ng/L) for 21 days. We then compared the response of exposed and unexposed males to sequentially presented large and small stimulus (unexposed) females. Due to a positive size-fecundity relationship, larger females are generally expected to be preferred by males. While we found no evidence that the size of a previously encountered female affected the amount of courtship or coercive 'sneak' mating behaviour performed by males during the second presentation, males from both exposure treatments conducted more frequent courting events towards larger females during both presentations, suggesting an absolute preference for greater female size. Further, across both presentations, 17β-TB exposure caused a shift in male mating strategy towards increased coercive sneaking behaviour, although male sequential investment into mating effort was not impacted at the tested dosage. In combination, our findings demonstrate that exposure to a field-realistic level of a widespread agricultural pollutant alters male mating strategies in fish, and contribute to a growing understanding of sub-lethal impacts of chemical contaminants on complex behaviours in wildlife.

Sorption and transport of trenbolone and altrenogest photoproducts in soil-water systems

This study evaluated the sorption and transport potential of seven phototransformation products of 17α-trenbolone, 17β-trenbolone, trendione, and altrenogest, along with the parent trienone steroids in batch and column soil-water systems. In batch systems, the target solutes exhibited linear isotherms, with values for sorption coefficients (log Koc) of parent steroids (2.46-2.76) higher than those for photoproducts (1.92-2.57). In column systems, the estimated retardation factors (Rsol) for parents (2.7-5.1) were ∼2-5 times higher than those for photoproducts (0.84-1.7). The log Koc (R2 = 0.75) and Rsol (R2 = 0.89-0.98) were well correlated with measured log Kow values, indicating that hydrophobic partitioning governed the soil-solute interaction of these biologically potent compounds in soil-water systems. These data indicated that photoproducts exhibited reduced sorption affinity and increased transport potential relative to more hydrophobic parent structures. In agroecosystems, traditional runoff management practices would be expected to exhibit reduced treatment effectiveness for photoproducts relative to the parent compounds of commonly used trienone steroids.