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The seasonal variations of estrogenic compounds and the estrogenicities of influent and effluent were investigated by chemical analysis and in vitro assay in a municipal sewage treatment plant in Wuhan (China). The levels of eight estrogenic compounds, including 17beta-estradiol (E2), estrone (E1), estriol (E3), diethylstilbestrol (DES), 17alpha-ethinylestradiol, nonylphenol (NP), 4-tert-octylphenol (OP), and bisphenol A (BPA), were measured by gas chromatography-mass spectrometry. Total estrogenic activity of sewage was quantitatively assessed using primary cultured hepatocytes of male Megalobrama amblycephala Yih using vitellogenin as a biomarker. The E2 equivalents (EEQs) obtained from the chemical analysis were consistent with those measured by bioassay. The natural (E1, E2, and E3) and synthetic (DES) estrogens, as well as NP, were the main contributors of the total EEQs of influent and effluent in the present study. The levels of natural estrogens E1 and E3 in the influent and effluent were higher in winter than in summer, whereas the situation for NP and OP was the reverse. The levels of E2, DES, and BPA varied little among different seasons. 17alpha-Ethinylestradiol was not detected in the influent and effluent. The estrogenicities of the influent and of the primary and secondary effluents were all higher in summer than in winter. Estrogenic activities in winter mainly originated from natural (E1, E2, and E3) and synthetic (DES) estrogens, whereas the increase of EEQs in summer was contributed by NP. The results from chemical analysis and bioassay demonstrate that estrogenic compounds cannot be entirely removed by the existing sewage treatment process, which should be further improved to protect aquatic ecosystems and human health.

Background: Bisphenol A (BPA), a well-known endocrine disruptor, is highly glucuronidated in the liver, and the resultant BPA-glucuronide (BPA-GA) is excreted primarily into bile. However, in rodents, prenatal exposure to low doses of BPA can adversely affect the fetus, despite the efficient drug-metabolizing systems of the dams. The transport mechanisms of BPA from mother to fetus are unknown. Objectives: To test our hypothesis that BPA-GA—an inactive metabolite—is passed through the placenta to the fetus, where it affects the fetus after reactivation, we investigated the placental transfer of BPA-GA and reactivation to BPA in the fetus. Methods: After performing uterine perfusion with BPA-GA in pregnant rats, we examined the expression and localization of the placental transporters for drug metabolites in the perfusate by reverse-transcriptase polymerase chain reaction and immunohistochemistry. We also investigated the deconjugation of BPA-GA in the fetus and examined uridine 5′-diphospho-glucuronosyltransferase (UGT) activity toward BPA and the expression of UGT isoforms in fetal liver. Results: We detected BPA-GA and deconjugated BPA in the fetus and amniotic fluid after perfusion. In the trophoblast cells, organic anion-transporting polypeptide 4a1 (Oatp4a1) was localized on the apical membrane, and multidrug resistance-associated protein 1 (Mrp1) was localized to the basolateral membrane. We observed deconjugation of BPA-GA in the fetus; furthermore, we found the expression of UGT2B1, which metabolizes BPA, to be quite low in the fetus. Conclusions: These results demonstrate that BPA-GA is transferred into the fetus and deconjugated in the fetus because of its vulnerable drug-metabolizing system.

The presence of natural estrogens estrone (E1), 17β-estradiol (E2), estriol (E3) and synthetic estrogen 17α-ethynylestradiol (EE2) in the aquatic environment has raised concerns because of their high potency as endocrine disrupting chemicals. The European Commission (EC) established a Watch List of contaminants of emerging concerns including E1, E2 and EE2. The proposed environmental quality standards (EQSs) are 3.6, 0.4, 0.035 ng/L, for E1, E2, EE2, respectively. A thorough evaluation of analytical procedures developed by several studies aiming to perform sampling campaigns in different European countries highlighted that the required limits of quantification in surface water were not reached, especially for EE2 and to a lesser extent for E2. Moreover, data regarding the occurrence of these contaminants in Belgian surface water are very limited. A sampling campaign was therefore performed on a wide range of rivers in Belgium (accounting for a total of 63 samples). The detection frequencies of E1, E2, E3 and EE2 were 100, 98, 86 and 48%, respectively. E1 showed the highest mean concentration (= 4.433 ng/L). In contrast, the mean concentration of EE2 was 0.042 ng/L. The risk quotients (RQs) were calculated based on the respective EQS of each analyte. The frequency of exceedance of the EQS was 31.7% for E1, EE2, while it increased to 44.4% for E2. The extent of exceedance of the EQS, represented by the 95th percentile of the RQ dataset, was higher than 1 for E1, E2, EE2. The use of a confusion matrix was investigated to try to predict the risk posed by E2, EE2, based on the concentration of E1.

Endocrine disrupting chemicals are one of the most important factors contributing to worldwide amphibian decline. The 4-nonylphenol (NP) is a degradation product of several compounds, such as detergents and pesticides, affecting the aquatic environment. Here, we test whether treatment with NP has an effect on developing ovarian tissue, nuclear abnormalities in erythrocytes, and body darkness in pre-metamorphic tadpoles of the bullfrog Lithobates catesbeianus. Tadpoles were exposed for 14 days to three different concentrations of NP (1, 10, and 100 μg/L) besides the control group, which was maintained only with water. After determining body coloration, animals were euthanized and gonads and blood were collected and processed for histology and genotoxic analysis. Even though most animals were females, intersex tadpoles were observed in control and treated groups and there were no males in any group. The highest concentration of NP showed an increase in atretic oocytes, but the area corresponding to somatic compartment and early and late germ cells were not affected. Furthermore, all treated groups presented higher amount of nuclear abnormalities in erythrocytes and body darkening when compared with the control group. These results suggest that NP causes genetic damage and morphological alterations in L. catesbeianus tadpoles by disrupting oogenesis, inducing genotoxicity and increasing body coloration. Its effects on gonadal development could cause future impairments in reproduction, while its deleterious effects on genotoxicity and body pigmentation could be used as a biomarker of effect to this compound.

With the widespread application of plastic pipes in drinking water distribution system, the effects of various leachable organic chemicals have been investigated and their occurrence in drinking water supplies is monitored. Most studies focus on the odor problems these substances may cause. This study investigates the potential endocrine disrupting effects of the migrating compound 2,4-di-tert-butylphenol (2,4-d-t-BP). The summarized results show that the migration of 2,4-d-t-BP from plastic pipes could result in chronic exposure and the migration levels varied greatly among different plastic pipe materials and manufacturing brands. Based on estrogen equivalent (EEQ), the migrating levels of the leachable compound 2,4-d-t-BP in most plastic pipes were relative low. However, the EEQ levels in drinking water migrating from four out of 15 pipes may pose significant adverse effects. With the increasingly strict requirements on regulation of drinking water quality, these results indicate that some drinking water transported with plastic pipes may not be safe for human consumption due to the occurrence of 2,4-d-t-BP. Moreover, 2,4-d-t-BP is not the only plastic pipe-migrating estrogenic compound, other compounds such as 2-tert-butylphenol (2-t-BP), 4-tert-butylphenol (4-t-BP), and others may also be leachable from plastic pipes.

Background and purpose Estrogenic compounds and antibiotic residues in environment are receiving significant attention because of their potential adverse effects on ecosystems and human health. The objectives of this study were to determine the occurrence and seasonal variability of eight kinds of estrogenic compounds and 14 antibiotics. The study developed an occurrence database of the estrogenic compounds and antibiotics in spatial and temporal scale in Jiulongjiang River, South China, to provide useful information for environmental management of this region. Methods Eight estrogenic compounds and 14 antibiotic compounds were detected in Jiulongjiang River from 19 sampling sites during high-flow and low-flow season in surface water. The samples were preconcentrated by solid-phase extraction for analysis. Eight estrogenic compounds were analyzed by gas chromatography mass spectrometry (Agilent 7890A-5975C), and antibiotics were determined by liquid chromatography-tandem mass spectrometry (LC–MS/MS) system (ABI 3200 Q TRAP). Results All target compounds could be detected, except 17α-ethynylestradiol, sulfamerazine, and ofloxacin. The median concentrations for seven estrogenic compounds ranged from 6.00 to 610.72 ng/L, with the detection frequency range of 16.00–100%. However, the detection frequencies of 13 antibiotics detected varied from 50% to 100%, with the median concentrations ranged from 0.89 to 117.97 ng/L. Seasonal variations were obvious for most estrogenic compounds in Jiulongjiang River, except for octylphenol and estriol. There were significant ( P  < 0.001) differences for three tetracyclines, sulfadiazine, and sulfamethoxazole between in low-flow season and in high-flow season. Besides, spatially considerable variations in the concentrations were observed for antibiotics, nonylphenol, octylphenol, and bisphenol A. Conclusion The Jiulongjiang River water was more seriously contaminated by diethylstilbestrol, estrone, sulfamethazine, and tetracyclines. Higher overall concentration levels of estrogenic compounds and antibiotics were detected in low-flow water than those in high-flow water. The pollution of estrogenic compounds and antibiotics in Jiulongjiang River mainly came from municipal sewage and livestock breeding activities.

This study evaluated the occurrence, distribution and risk assessment of nine estrogenic compounds found in 29 source water sites in Ningbo City, China. They included 21 reservoirs, five river sites and three wells. The nine estrogenic compounds included estrone (E1), 4-n-nonylphenol (NP), 17α-ethynylestradiol (EE2), diethylstilbestrol (DES), estriol (E3), 17β-estradiol (E2), 4-t-octylphenol (OP), 17β-estradiol-17-valerate (EV), and bisphenol A (BPA). Generally, most of these estrogenic compounds were not detected in samples. Among estrogens detected, we found high concentrations of BPA up to μg/L levels while NP had the highest detection frequency of all estrogens in all samples. Samples taken from rivers had a higher detection frequency of estrogenic compounds than samples taken from reservoirs and wells. According to risk quotient (RQ) calculations for aquatic organisms living in source water contaminated by estrogenic compounds, the Fenghua and Yao rivers were at high risk. Results from this study can provide insight into selecting appropriate source water based on the accurate identification of compound and/or element contamination through the coupled analysis of their distribution and risk assessment.

Traumatic Brain Injury TBI is a major public health problem causing high rates of morbidity and mortality. Currently, there are no effective pharmaceutical strategies to prevent its secondary injury cascades, which includes oxidative stress and metabolic dysfunction that lead to increased tissue damage and cellular death. Although neuroprotective strategies using different approaches have been assessed to counteract TBI-induced neuroinflammation, none has shown promising results. In fact, most of these approaches have focused on neuronal population, rather than glial cells. The role of glial cells, mainly astrocytes, has been extensively studied in recent years due to their direct effect on the lesion and their ability to control pathological conditions associated with TBI. Experimental strategies targeting astrocytes are an important asset to reduce neuroinflammation and therefore improve the outcome in the damaged brain. More recently, estrogenic compounds have been used to control astroglial reactivity upon brain injury and also to modulate the expression of several genes involved in neural development, synaptic connectivity and survival of neurons. In this context, these neurosteroids are promising molecules thanks to their ability to modify brain response to injury by regulating astrogliosis. In this work, we highlight the role played by astrocytes during a pathological event, and discuss the potential effects of neuroactive steroids as a promising therapeutic approach to reduce brain damage.

In this study, the effects of environmental factors, including humic acid (HA), pH, ionic strength, and the coexistence of competing estrogenic compounds, on the adsorption of four typical estrogenic compounds, estrone (E1), 17β-estradiol (E2), 17α-ethinylestradiol (EE2), and bisphenol A (BPA), were studied by molecularly imprinted polymer (MIP). The adsorption capacities of MIP for E2 were 116.3, 118.5, 127.0, and 109.0 µmol/g at HA concentrations of 0, 5, 15, and 20 mg/L in total organic carbon, respectively, while the corresponding adsorption capacities of nontemplate imprinted polymer (NIP) for E2 were 98.1, 109.4, 113.8, and 98.0 µmol/g. This implied that no significant trend could be found with the increasing HA concentrations. Furthermore, the selective adsorption capacity, represented by the difference in adsorption capacities between MIP and NIP, was not affected significantly. Similar observations were noted for E1, EE2, and BPA in the presence of HA. Ionic strength did not exert a considerable influence on the adsorption capacities of MIP and NIP for E1, E2, and BPA. However, at 0 mM of NaCl, EE2 adsorption capacities of MIP and NIP were 124.7 and 111.7 µmol/g, respectively, while the corresponding adsorption capacities were 144.7 and 138.2 µmol/g at 10 mM of NaCl due to the increased hydrophobic interactions. Nevertheless, the selective adsorption capacity was not significantly affected by the range of ionic strength tested in this study. The study demonstrated that there was no significant effect of pH on the adsorption capacity of both MIP and NIP from pH 3.1 to 9 and that no considerable effect of pH on selective adsorption capacity of MIP could be established. However, the adsorption capacities of MIP and NIP for E2 at pH 9 were 95.1 and 82.9 µmol/g, while at pH 11, the adsorption capacities were 12.1 and 5.9 µmol/g correspondingly. This means that adsorption capacity and selective adsorption capacity were influenced significantly due to the ionization of target compounds. A similar trend was observed for E1, EE2, and BPA. The study on the effect of the coexistence of competing estrogenic compounds demonstrated that selective adsorption capacities of MIP can be influenced. Differences between MIP and NIP for E1, E1, EE2, and BPA under competing conditions were 8.8, 6.8, 10.2, and 4.2 µmol/g, respectively, while the corresponding differences were 12.6, 18.2, 13.0, and 9.8 µmol/g, respectively, when adsorbed individually.

Background: There is concern about the potential risk posed by compounds with estrogen-like activity present in the environment. As previous studies have shown that combined exposure to such compounds results in dose additivity, it should be possible to assess estrogen exposure with suitable biomarkers of effect. Objectives: Our goal was to identify candidate protein biomarkers of effect for estrogenic compounds. Methods: In the search for biomarkers, we assessed the effect of several estrogenic compounds on the expression profile of proteins in breast-derived cell lines varying in their estrogen receptor (ER) phenotype using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. We identified responsive proteins, after separating them by SDS-polyacrylamide gel electrophoresis, and analyzing the trypsin-digested proteins by tandem mass spectrometry. Results: The estrogenic compounds 17β-estradiol, genistein, bisphenol A, and endosulfan produced similar protein profile changes in MCF-7 cells (phenotype: ERα⁺/ERβ⁺), but had no effect on MDA-MB-231 (ERα⁻/ERβ⁺), MCF-10F (ERα⁻/ERβ⁺), or MCF-10A (ERα⁻/ERβ⁻) cells. The most responsive proteins in MCF-7 cells were identified as histones H2A, H2B, H3, and H4. Histone levels were not increased in cell lines that showed no proliferative response to estrogens despite their rapid intrinsic growth rate in culture. Conclusion: Our results indicate that ER-mediated cell proliferation results in up-regulation of core histone proteins.