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Background: Zearalenone (ZEN), a secondary metabolite of Fusarium fungi, is one of the most common mycotoxins in global food supplies such as cereal grains and processed food. ZEN and its metabolites are commonly referred to as mycoestrogens, due to their ability to directly bind nuclear estrogen receptors α (ER-α) and β (ER-β). Zeranol, a synthetic mycoestrogen, is administered to U.S. cattle as a growth promoter. Despite widespread human exposure and ample evidence of adverse reproductive impacts in vitro and in vivo, there has been little epidemiological research on the health impacts of ZEN exposure during pregnancy. The objective of our study was to examine associations between ZEN and gestational weight gain (GWG). Methods: Urine samples were collected in each trimester from pregnant participants in the UPSIDE cohort (n = 286, Rochester, NY, USA). High performance liquid chromatography and high-resolution tandem mass spectrometry were used to quantify concentrations of ZEN as well as ∑mycoestrogens (composite sum of ZEN metabolites; ng/ml). Maternal weights at clinical visits were abstracted from medical records. We fitted longitudinal models of specific-gravity adjusted, log-transformed ZEN and ∑mycoestrogens in relation to total GWG (kilograms) and GWG rate (kilograms/week). We additionally examined risk of excessive GWG (in relation to Institute of Medicine guidelines) and considered effect modification by fetal sex. Results: ZEN and ∑mycoestrogens were detected in > 93% and > 95% of samples, respectively. Mycoestrogen concentrations were positively associated with total GWG (ZEN β:0.50 kg; 95%CI: 0.13, 0.87) and GWG rate (ZEN β:0.20 kg/week; 95%CI: 0.01, 0.03). Associations tended to be stronger among participants carrying male (versus female) fetuses and results were robust to adjustment for diet. Conclusions: Mycoestrogen exposure during pregnancy may contribute to greater GWG. Future research is needed to understand potential influences on downstream maternal and offspring health. [ABSTRACT FROM AUTHOR]

Abstract Background Zearalenone (ZEN), a secondary metabolite of Fusarium fungi, is one of the most common mycotoxins in global food supplies such as cereal grains and processed food. ZEN and its metabolites are commonly referred to as mycoestrogens, due to their ability to directly bind nuclear estrogen receptors α (ER-α) and β (ER-β). Zeranol, a synthetic mycoestrogen, is administered to U.S. cattle as a growth promoter. Despite widespread human exposure and ample evidence of adverse reproductive impacts in vitro and in vivo, there has been little epidemiological research on the health impacts of ZEN exposure during pregnancy. The objective of our study was to examine associations between ZEN and gestational weight gain (GWG). Methods Urine samples were collected in each trimester from pregnant participants in the UPSIDE cohort (n = 286, Rochester, NY, USA). High performance liquid chromatography and high-resolution tandem mass spectrometry were used to quantify concentrations of ZEN as well as ∑mycoestrogens (composite sum of ZEN metabolites; ng/ml). Maternal weights at clinical visits were abstracted from medical records. We fitted longitudinal models of specific-gravity adjusted, log-transformed ZEN and ∑mycoestrogens in relation to total GWG (kilograms) and GWG rate (kilograms/week). We additionally examined risk of excessive GWG (in relation to Institute of Medicine guidelines) and considered effect modification by fetal sex. Results ZEN and ∑mycoestrogens were detected in > 93% and > 95% of samples, respectively. Mycoestrogen concentrations were positively associated with total GWG (ZEN β:0.50 kg; 95%CI: 0.13, 0.87) and GWG rate (ZEN β:0.20 kg/week; 95%CI: 0.01, 0.03). Associations tended to be stronger among participants carrying male (versus female) fetuses and results were robust to adjustment for diet. Conclusions Mycoestrogen exposure during pregnancy may contribute to greater GWG. Future research is needed to understand potential influences on downstream maternal and offspring health.

Risk assessment primarily relies on toxicological data of individual substances, with limited information on combined effects. Recent in vitro experiments using Ishikawa cells, an endometrial carcinoma cell line expressing both estrogen receptor isoforms, demonstrated interactive effects of phyto- and mycoestrogens. The mycoestrogens, zearalenone (ZEN), and α-zearalenol (α-ZEL) exhibited significantly enhanced estrogenic responses in the presence of isoflavones (ISF), depending on substance ratios and concentrations. This study investigated the impact of phyto- and mycoestrogen combinations on estrogenic response following OECD guideline 455, utilizing hERα-HeLa-9903 cells. Test substances included mycoestrogens (ZEN and α-ZEL) and isoflavones (genistein (GEN), daidzein (DAI), and S-equol (EQ), a gut microbial metabolite of DAI). Mycoestrogens were tested in the range of 0.001 to 100 nM, while isoflavones were used at concentrations 1000 times higher based on relevant occurrence ratios. Results showed that ZEN and α-ZEL induced ERα-dependent luciferase expression in concentrations above 1 nM and 0.01 nM, respectively. However, ISF caused a superinduction of the luciferase signal above 1 µM. A superinduction is characterized by an unusually strong or heightened increase in the activity of the luciferase enzyme. This signal is not affected by the estrogen receptor antagonist 4-hydroxytamoxifen (4-OH-TAM), which was additionally used to verify whether the increase of signal is a true reflection of receptor activation. This superinduction was observed in all combinations of ZEN and α-ZEL with ISFs. Contrary to the luciferase activity findings, RT-qPCR experiments and a stability approach revealed lower real ERα activation by ISFs than measured in the ONE-Glo™ luciferase test system. In conclusion, the OECD protocol 455 appears unsuitable for testing ISFs due to their superinduction of luciferase and interactions with the test system, resulting in experimental artifacts. Further studies are necessary to explore structure–activity relationships within polyphenols and clarify the test system's applicability. [ABSTRACT FROM AUTHOR]

Zearalenone and its metabolites, a group of endocrine disrupting mycotoxins, have been linked to adverse reproductive health effects. They cross the placental barrier, potentially reaching the fetus. In this study, we adapted and optimized our protocol previously used for urine, to measure these mycotoxins in human placentas. We combined a supported liquid extraction step using Chem Elut cartridges with solid phase extraction on Discovery® DSC-NH2 tubes. The optimized extraction efficiencies were between 68 and 80% for all metabolites. Analysis was performed by UHPLC-HRMS using a Betasil™ Phenyl-Hexyl column eluted with a gradient of acetonitrile-methanol-water. The chromatography method separated all analytes in under 15 min. Validation experiments confirmed the method's sensitivity, with LODs ranging from 0.0055 to 0.011 pg/mg tissue. The method was linear over a range of 0.0025–1.5 pg/mg tissue with R2 values ≥ 0.994. Precision and accuracy calculations ranged from 4.7–7.9% and 0.6–6.7% respectively. The method was then successfully applied to a subset of placenta samples (n = 25) collected from an ongoing prospective birth cohort. Interestingly, 92% of the samples contained at least one measurable zearalenone metabolite, providing initial indication of potentially widespread exposure during pregnancy.

Zearalenone (ZEN) is produced by Fusarium species contaminating various agriculture crops. In this study, the effects of ZEN and its metabolites α-zearalenol (α-ZEL), and β-zearalenol (β-ZEL) on the formation of carcinogenic oestrogen-catechols in MCF-7 cells were investigated. To assess the effects of mycoestrogens on the activity of cytochrome P450 1A1 and CYP1B1, the rate of ethoxyresorufin O-deethylation (EROD-assay) was measured. The effects of mycoestrogens on the expression of CYP 1A1, CYP 1B1, aryl-hydrocarbon receptor (AhR), and oestrogen receptor alpha (ERα) were determined by qPCR. The catechol-O-methyltransferase (COMT) activity was measured as the ratio of the methoxy metabolites of oestradiol. Results show that mycoestrogens inhibited significantly the CYP1-dependent EROD activities. In the presence of selective inhibitors, mycoestrogens reduced CYP 1A1 and enhanced CYP 1B1 activity. Quantitative PCR analyses demonstrated the upregulation of AhR and confirmed the selective effect of mycoestrogens on CYP1 expression levels and the decline of the CYP 1A1/CYP 1B1 ratio. Mycoestrogens increased the ratio of 4-MeOE to 2-MeOE2 formation significantly (P < 0.05). Our results suggest that the tested mycoestrogens increase the production of CYP1B1-mediated oestrogen catechol metabolites, directing the biotransformation of E2 towards 4-OHE2, which has been identified earlier as a crucial factor in oestrogen-induced tumour initiation. [ABSTRACT FROM AUTHOR]

Humans and animals are exposed to multiple substances in their food and feed that might have a negative health impact. Among these substances, the Fusarium mycoestrogen zearalenone (ZEN) and its metabolites α-zearalenol (α-ZEL) and α-zearalanol (α-ZAL) are known to possess endocrine disruptive properties. In a mixed diet or especially animal feed, these potential contaminants might be ingested together with naturally occurring phytoestrogens such as soy isoflavones. So far, risk assessment of potential endocrine disruptors is usually based on adverse effects of single compounds whereas studies investigating combinatorial effects are scarce. In the present study, we investigated the estrogenic potential of mycoestrogens and the isoflavones genistein (GEN), daidzein (DAI) and glycitein (GLY) as well as equol (EQ), the gut microbial metabolite of DAI, in vitro alone or in combination, using the alkaline phosphatase (ALP) assay in Ishikawa cells. In the case of mycoestrogens, the tested concentration range included 0.001 to 10 nM with multiplication steps of 10 in between, while for the isoflavones 1000 times higher concentrations were investigated. For the individual substances the following order of estrogenicity was obtained: α-ZEL > α-ZAL > ZEN > GEN > EQ > DAI > GLY. Most combinations of isoflavones with mycoestrogens enhanced the estrogenic response in the investigated concentrations. Especially lower concentrations of ZEN, α-ZEL and α-ZAL (0.001—0.01 nM) in combination with low concentrations of GEN, DAI and EQ (0.001—0.1 µM) strongly increased the estrogenic response compared to the single substances. [ABSTRACT FROM AUTHOR]

Zearalenone (ZEN) is a fungal-derived toxin found in global food supplies including cereal grains and processed foods, impacting populations worldwide through diet. Because the chemical structure of ZEN and metabolites closely resembles 17β-estradiol (E2), they interact with estrogen receptors α/β earning their designation as 'mycoestrogens'. In animal models, gestational exposure to mycoestrogens disrupts estrogen activity and impairs fetal growth. Here, our objective was to evaluate relationships between mycoestrogen exposure and sex steroid hormone concentrations in maternal circulation and cord blood for the first time in humans. In each trimester, pregnant participants in the UPSIDE study (n = 297) provided urine for mycoestrogen analysis and serum for hormone analysis. At birth, placental mycoestrogens and cord steroids were measured. We fitted longitudinal models examining log-transformed mycoestrogen concentrations in relation to log-transformed hormones, adjusting for covariates. Secondarily, multivariable linear models examined associations at each time point (1st, 2nd, 3rd trimesters, delivery). We additionally considered effect modification by fetal sex. ZEN and its metabolite, α-zearalenol (α-ZOL), were detected in >93% and >75% of urine samples; >80% of placentas had detectable mycoestrogens. Longitudinal models from the full cohort exhibited few significant associations. In sex-stratified analyses, in pregnancies with male fetuses, estrone (E1) and free testosterone (fT) were inversely associated with ZEN (E1 %Δ: −6.68 95%CI: −12.34, −0.65; fT %Δ: −3.22 95%CI: −5.68, −0.70); while α-ZOL was positively associated with E2 (%Δ: 5.61 95%CI: −1.54, 9.85) in pregnancies with female fetuses. In analysis with cord hormones, urinary mycoestrogens were inversely associated with androstenedione (%Δ: 9.15 95%CI: 14.64, −3.30) in both sexes, and placental mycoestrogens were positively associated with cord fT (%Δ: 37.13, 95%CI: 4.86, 79.34) amongst male offspring. Findings support the hypothesis that mycoestrogens act as endocrine disruptors in humans, as in animal models and livestock. Additional work is needed to understand impacts on maternal and child health. [ABSTRACT FROM AUTHOR]

Abstract Background Despite evidence of the endocrine disrupting properties of zearalenone (ZEN) and alpha-zearalanol (zeranol, α-ZAL), they have been minimally studied in human populations. In previous cross-sectional analyses, we demonstrated that 9–10 years old girls with detectable urinary ZEN were of shorter stature and less likely to have reached the onset of breast development than girls with undetectable urinary ZEN. The aim of this study was to examine baseline concentrations of ZEN, (α-ZAL), and their phase-1 metabolites in relation to subsequent growth and timing of menarche using 10 years of longitudinal data. Methods Urine samples were collected from participants in the Jersey Girl Study at age 9–10 (n = 163). Unconjugated ZEN, (α-ZAL), and their metabolites were analyzed using high performance liquid chromatography and tandem mass spectrometry. Information on height, weight, and pubertal development was collected at a baseline visit with annual follow-up by mail thereafter. Cox regression was used to evaluate time to menarche in relation to baseline ZEN, (α-ZAL), and total mycoestrogen exposure. Z-scores for height and weight were used in mixed models to assess growth. Results Mycoestrogens were detectable in urine in 78.5% of the girls (median ZEN: 1.02 ng/ml, range 0–22.3). Girls with detectable urinary concentrations of (α-ZAL) and total mycoestrogens (sum of ZEN, (α-ZAL) and their metabolites) at baseline were significantly shorter at menarche than girls with levels below detection (p = 0.04). ZEN and total mycoestrogen concentrations were inversely associated with height- and weight-z-scores at menarche (adjusted β = − 0.18, 95% CI: -0.29, − 0.08, and adjusted β = − 0.10, 95% CI: -0.21, 0.01, respectively). Conclusion This study supports and extends our previous results suggesting that exposure to ZEN, (α-ZAL), and their metabolites is associated with slower growth and pubertal development in adolescent girls.

Zearalenone (ZEA) is produced by Fusarium species and a common contaminant in food. ZEA and its metabolites, α- and β-zearalenol, α- and β-zearalanol, and zearalanone, are mycoestrogens that can interfere with estrogen signaling. High levels of mycoestrogens reduced female fertility in farm animals and rodents, in which adverse effects of mycoestrogens on major events in female reproduction, including ovarian folliculogenesis, ovulation, ovarian steroidogenesis, fertilization, preimplantation embryo development and transport, embryo implantation, placentation, parturition, and lactation, have been reported in different experimental settings. Here, we review the in vivo effects of mycoestrogens on the main events in female reproduction.

Xenoestrogenic mycotoxins may contaminate food and feed posing a public health issue. Besides the zearalenone group, the Alternaria toxin alternariol (AOH) has been described as a potential mycoestrogen. However, the estrogenicity of Alternaria toxins is still largely overlooked and further data are needed to better describe the group toxicity. In the frame of risk assessment, mixed in silico/in vitro approaches already proved to be effective first-line analytical tools. An integrated in silico/in vitro approach was used to investigate the effects of metabolic and chemical modifications on the estrogenicity of AOH. Among the considered modifications, methylation was found critical for enhancing estrogenicity (as seen for alternariol monomethyl ether (AME)) while hydroxylation and glucuronidation had the opposite effect (as seen for 4-hydroxy AOH and 4-hydroxy AME). The structure-activity relationship analysis provided the structural rationale. Our results provide insights to design more efficient risk assessment studies expanding knowledge over the group toxicity. [ABSTRACT FROM AUTHOR]

Xenoestrogens are widely diffused in the environment and in food, thus a large portion of human population worldwide is exposed to them. Among alimentary xenoestrogens, phytoestrogens (PhyEs) are increasingly being consumed because of their potential health benefits, although there are also important risks associated to their ingestion. Furthermore, other xenoestrogens that may be present in food are represented by other chemicals possessing estrogenic activities, that are commonly defined as endocrine disrupting chemicals (EDCs). EDCs pose a serious health concern since they may cause a wide range of health problems, starting from pre-birth till adult lifelong exposure. We herein provide an overview of the main classes of xenoestrogens, which are classified on the basis of their origin, their structures and their occurrence in the food chain. Furthermore, their either beneficial or toxic effects on human health are discussed in this review. [ABSTRACT FROM AUTHOR]

Zearalenone and its metabolites, a group of endocrine disrupting mycotoxins, have been linked to adverse reproductive health effects. They cross the placental barrier, potentially reaching the fetus. In this study, we adapted and optimized our protocol previously used for urine, to measure these mycotoxins in human placentas. We combined a supported liquid extraction step using Chem Elut cartridges with solid phase extraction on Discovery® DSC-NH2 tubes. The optimized extraction efficiencies were between 68 and 80% for all metabolites. Analysis was performed by UHPLC-HRMS using a Betasil™ Phenyl-Hexyl column eluted with a gradient of acetonitrile-methanol-water. The chromatography method separated all analytes in under 15 min. Validation experiments confirmed the method's sensitivity, with LODs ranging from 0.0055 to 0.011 pg/mg tissue. The method was linear over a range of 0.0025-1.5 pg/mg tissue with R 2 values ≥ 0.994. Precision and accuracy calculations ranged from 4.7-7.9% and 0.6-6.7% respectively. The method was then successfully applied to a subset of placenta samples (n = 25) collected from an ongoing prospective birth cohort. Interestingly, 92% of the samples contained at least one measurable zearalenone metabolite, providing initial indication of potentially widespread exposure during pregnancy., Competing Interests: We declare that none of the authors have any known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Recently, magnetic solid-phase extraction has gained interest because it presents various operational advantages over classical solid-phase extraction. Furthermore, magnetic nanoparticles are easy to prepare, and various materials can be used in their synthesis. In the literature, there are only few studies on the determination of mycoestrogens in milk, although their carryover in milk has occurred. In this work, we wanted to develop the first (to the best of our knowledge) magnetic solid-phase extraction protocol for six mycoestrogens from milk, followed by liquid chromatography and tandem mass spectrometry analysis. Magnetic graphitized carbon black was chosen as the adsorbent, as this carbonaceous material, which is very different from the most diffuse graphene and carbon nanotubes, had already shown selectivity towards estrogenic compounds in milk. The graphitized carbon black was decorated with Fe3O4, which was confirmed by the characterization analyses. A milk deproteinization step was avoided, using only a suitable dilution in phosphate buffer as sample pretreatment. The overall process efficiency ranged between 52 and 102%, whereas the matrix effect considered as signal suppression was below 33% for all the analytes even at the lowest spiking level. The obtained method limits of quantification were below those of other published methods that employ classical solid-phase extraction protocols. [ABSTRACT FROM AUTHOR]

Estrogens, phytoestrogens, and mycoestrogens may enter into the surface waters from different sources, such as effluents of municipal wastewater treatment plants, industrial plants, and animal farms and runoff from agricultural areas. In this work, a multiresidue analytical method for the determination of 17 natural estrogenic compounds, including four steroid estrogens, six mycoestrogens, and seven phytoestrogens, in river water samples has been developed. (FeO)-based magnetic nanoparticles coated by polydopamine (FeO@pDA) were used for dispersive solid-phase extraction, and the final extract was analyzed by ultra-high performance liquid chromatography coupled with tandem mass spectrometry. The FeO magnetic nanoparticles were prepared by a co-precipitation procedure, coated by pDA, and characterized by scanning electron microscopy, infrared spectroscopy, and elemental analysis. The sample preparation method was optimized in terms of extraction recovery, matrix effect, selectivity, trueness, precision, method limits of detection, and method limits of quantification (MLOQs). For all the 17 analytes, recoveries were >70 % and matrix effects were below 30 % when 25 mL of river water sample was treated with 90 mg of FeO@pDA nanoparticles. Selectivity was tested by spiking river water samples with 50 other compounds (mycotoxins, antibacterials, conjugated hormones, UV filters, alkylphenols, etc.), and only aflatoxins and some benzophenones showed recoveries >60 %. This method proved to be simple and robust and allowed the determination of natural estrogenic compounds belonging to different classes in surface waters with MLOQs ranging between 0.003 and 0.1 μg L. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Highlights: [•] Natural and anthropogenic sources of estrogen-like compounds. [•] Estrogens, mycoestrogens, phytoestrogens, alkylphenols occurrence in food. [•] Sample preparation and detection of estrogenic compounds in food. [•] Issues in GC–MS and LC–MS determination. [•] New LC developments and MS trends in the field. [Copyright &y& Elsevier]

ABSTRACT Introduction Exposure to phytoestrogens and mycoestrogens has emerged as a public health issue due to their potentially endocrine disruption activities resulting from direct interaction with sex-steroid hormone receptors. There is a significant requirement for comprehensive, reproducible methods to determine the extent of estrogen mimicry by compounds encountered in the environment to estimate risk:benefit ratios, particularly in humans. Objective To develop a systematic approach for assessing recognition of chemically diverse compounds by human estrogen receptor proteins to aid in their assessment as endocrine disruptor compounds (EDCs). Methods Recombinant human estrogen receptor-α protein (rhERα) was expressed in Saccharomyces cervisiae as an ubiquitin fusion under control of a CUP1 promoter and partially purified with heparin affinity chromatography in the unliganded state. A novel radio-ligand binding array was developed to evaluate structurally diverse compounds, both naturally occurring and synthetic, for estrogen binding activity and affinity. Results Binding affinities of suspected estrogen mimics for rhERα were calculated over a range of [3H]estradiol-17β concentrations using Lundon OneSite® and Compete® software. Conclusion β-zearalanol, a mycoestrogen similar to zearalenone used as an ICCVAM validation substance for the in vitro estrogen receptor binding assays (ICCAM report), was employed as a model estrogen mimic to illustrate the approach, methods and calculations using these techniques. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Background: Despite extensive research and interest in endocrine disruptors, there are essentially no epidemiologic studies of estrogenic mycotoxins, such as zeranol and zearalenone (ZEA). ZEA mycoestrogens are present in grains and other plant foods through fungal contamination, and in animal products (e.g., meat, eggs, dairy products) through deliberate introduction of zeranol into livestock to enhance meat production, or by indirect contamination of animals through consumption of contaminated feedstuff. Zeranol is banned for use in animal husbandry in the European Union and other countries, but is still widely used in the US. Surprisingly, little is known about the health effects of these mycoestrogens, including their impact on puberty in girls, a period highly sensitive to estrogenic stimulation. Objectives and methods: We conducted a cross-sectional analysis among 163 girls, aged 9 and 10years, participating in the Jersey Girl Study to measure urinary mycoestrogens and their possible relationship to body size and development. Results: We found that mycoestrogens were detectable in urine in 78.5% of the girls, and that urinary levels were predominantly associated with beef and popcorn intake. Furthermore, girls with detectable urinary ZEA mycoestrogen levels tended to be shorter and less likely to have reached the onset of breast development. Conclusions: Our findings suggest that ZEA mycoestrogens may exert anti-estrogenic effects similar to those reported for isoflavones. To our knowledge, this was the first evaluation of urinary mycoestrogens and their potential health effects in healthy girls. However, our findings need replication in larger studies with more heterogeneous populations, using a longitudinal approach. [Copyright &y& Elsevier]

The effectiveness of removal of chosen compounds from the mycoestrogens group with the use of coagulation, activated carbon sorption and nanofiltration operated as unit processes or integrated systems was determined during the study. The removal of mycoestrogens by means of coagulation did not exceed 34% and the effectiveness of the process depended on the type of coagulant and its dose. Nanofiltration allowed to remove the considered compounds in the range from 70 to 88% depending on the compound type. On the other hand, during activated carbon sorption, in which powdered carbon of the dose equal 100 mg/dm³ was applied, the degree of removal of mycoestrogens was equal to 94%. The increase of the effectiveness of mycoestrogens removal for lower activated carbon doses, which in lower extent eliminated the investigated compound, allowed to apply post-sorption nanofiltration. Additionally, in such a water treatment system the complete removal of organic substances was obtained. The similar dependence was observed for the integrated coagulation-nanofiltration system. [ABSTRACT FROM AUTHOR]

Natural toxins such as phytotoxins and mycotoxins have been studied in food and feed for decades, but little attention has yet been paid to their occurrence in the environment. Because of increasing awareness of the presence and potential relevance of micropollutants in the environment, phytotoxins and mycotoxins should be considered and investigated as part of the chemical cocktail in natural samples. Here, we compile chemical analytical methods to determine important phytotoxins (i.e. phenolic acids, quinones, benzoxazinones, terpenoids, glycoalkaloids, glucosinolates, isothiocyanates, phytosterols, flavonoids, coumestans, lignans, and chalcones) and mycotoxins (i.e. resorcyclic acid lactones, trichothecenes, fumonisins, and aflatoxins) in environmentally relevant matrices such as surface water, waste water-treatment plant influent and effluent, soil, sediment, manure, and sewage sludge. The main problems encountered in many of the reviewed methods were the frequent unavailability of suitable internal standards (especially isotope-labelled analogues) and often absent or fragmentary method optimization and validation. [ABSTRACT FROM AUTHOR]

Abstract: The mycoestrogen zearalenone (ZEA) is found worldwide as a contaminant in cereals and grains, including maize and soybeans. Despite its non-steroidal structure, ZEA activates estrogen receptors resulting in functional and morphological alteration in reproductive organs. Among farm animals, pigs are considered to be the most sensitive species, and clinical signs of exposure include ovarian atrophy, prolonged estrus intervals, persistent corpora lutea, decreased fertility and stillbirth. Controlled experiments demonstrated that the intensity of these effects depends upon the reproductive status and is more pronounced in prepubertal gilts. ZEA interacts not only with both types of estrogen receptors but is also a substrate for hydroxysteroid dehydrogenases, which convert it into two stereoisomeric metabolites, α-zearalenol and β-zearalenol. A second reduction step yields the two minor metabolites α-zearalanol and β-zearalanol. Alpha-hydroxylation results in an increase in estrogenic potency as compared to the parent compound, and the species-specific rate of alpha-hydroxylation may account for the susceptibility of certain animal species, including pigs, towards ZEA exposure. Another factor that might contribute to the species-specific sensitivity is the glucuronidation capacity inactivating ZEA as well as its metabolites. In comparison with other animal species, certain pig breeds have a low glucuronidation capacity, and hence this may cause a delayed inactivation of the ZEA. Experiments in vivo and in vitro indicate that ZEA and its metabolites are substrates for various enzymes involved in steroid metabolism. Hence, considering the interaction with estrogen receptors mentioned above and the modulation of enzyme kinetics, ZEA is grouped with the compounds known collectively as endocrine disrupters. This classification is substantiated by the findings that maternal exposure to ZEA affects the development and reproductive activity in the offspring (F1), as demonstrated in rodent studies. The diversity of biological effects also seems to account for the significant variability in the outcome of clinical trials conducted with pigs of different age groups, and suggests that adverse effects associated with exposure to ZEA occur at concentrations in feed that do not cause obvious clinical signs. [Copyright &y& Elsevier]

Soybeans are a common ingredient of animal feed. They contain isoflavones, which are known to act as phytoestrogens in animals. Isoflavones were described to have beneficial effects on farm animals. However, there are also reports of negative outcomes after the consumption of isoflavones. This review summarizes the current knowledge of metabolization of isoflavones (including the influence of the microbiome, phase I and phase II metabolism), as well as the distribution of isoflavones and their metabolites in tissues. Furthermore, published studies on effects of isoflavones in livestock species (pigs, poultry, ruminants, fish) are reviewed. Moreover, published studies on occurrence of isoflavones in feed materials and co-occurrence with zearalenone are presented and are supplemented with our own survey data. [ABSTRACT FROM AUTHOR]

A simple, fast, and reproducible method for the simultaneous determination of natural estrogens and mycoestrogens (resorcylic acid lactones) in milk by ultrahigh-performance liquid chromatography combined with electrospray ionization triple quadrupole tandem mass spectrometry (UHPLC/ESI-MS/MS) is described. The extraction was carried out by solid-phase extraction (SPE) using graphitized carbon black as solid sorbent. The use of carbon black allowed us to avoid any type of sample pretreatment, and the extraction was performed simply by diluting milk samples in water. Correlation coefficient values were obtained in the range between 0.9991 and 1, with good recoveries (67-107% at the lowest spiked level), repeatability (4.8-16.8%), and reproducibility (3.2-16.3%). Moreover, a very low matrix effect was observed for both estrogens and mycoestrogens. With respect to a previous method based on SPE with Oasis MAX cartridges, the one here described allowed us to detect all the analytes under investigation, at the lowest tested concentration level, including free estrogens (in particular estriol). Finally, the developed UHPLC/ESI-MS/MS method was applied to the analysis of some whole milk samples from different lactating animals (cow, goat, and donkey) as well as ultrahigh-temperature-treated cow milk and powder milk samples.