Analysis of selected pesticides and alkylphenols in human cord blood by gas chromatograph-mass spectrometer

Emerging Contaminants and New POPs (PFAS and HBCDD) in Endangered Southern Resident and Bigg's (Transient) Killer Whales (Orcinus orca): In Utero Maternal Transfer and Pollution Management Implications

Killer whales (Orcinus orca) have been deemed one of the most contaminated cetacean species in the world. However, concentrations and potential health implications of selected 'contaminants of emerging concern' (CECs) and new persistent organic pollutants (POPs) in endangered Southern Resident and threatened Bigg's (Transient) killer whales in the Northeastern Pacific (NEP) have not yet been documented. Here, we quantify CECs [alkylphenols (APs), triclosan, methyl triclosan, and per- and polyfluoroalkyl substances (PFAS)] and new POPs [hexabromocyclododecane (HBCCD), PFOS, PFOA, and PFHxS] in skeletal muscle and liver samples of these sentinel species and investigate in utero transfer of these contaminants. Samples were collected from necropsied individuals from 2006 to 2018 and analyzed by LC-MS/MS or HRBC/HRMS. AP and PFAS contaminants were the most prevalent compounds; 4-nonylphenol (4NP) was the predominant AP (median 40.84 ng/g ww), and interestingly, 7:3-fluorotelomer carboxylic acid (7:3 FTCA) was the primary PFAS (median 66.35 ng/g ww). Maternal transfer ratios indicated 4NP as the most transferred contaminant from the dam to the fetus, with maternal transfer rates as high as 95.1%. Although too few killer whales have been screened for CECs and new POPs to infer the magnitude of contamination impact, these results raise concerns regarding pathological implications and potential impacts on fetal development and production of a viable neonate. This study outlines CEC and new POP concentrations in killer whales of the NEP and provides scientifically derived evidence to support and inform regulation to mitigate pollutant sources and contamination of Southern Resident killer whale critical habitat and other marine ecosystems.

Endocrine-Disrupting Effects of Bisphenol A on the Cardiovascular System: A Review

Currently, the plastic monomer and plasticizer bisphenol A (BPA) is one of the most widely used chemicals. BPA is present in polycarbonate plastics and epoxy resins, commonly used in food storage and industrial or medical products. However, the use of this synthetic compound is a growing concern, as BPA is an endocrine-disrupting compound and can bind mainly to estrogen receptors, interfering with different functions at the cardiovascular level. Several studies have investigated the disruptive effects of BPA; however, its cardiotoxicity remains unclear. Therefore, this review’s purpose is to address the most recent studies on the implications of BPA on the cardiovascular system. Our findings suggest that BPA impairs cardiac excitability through intracellular mechanisms, involving the inhibition of the main ion channels, changes in Ca²⁺ handling, the induction of oxidative stress, and epigenetic modifications. Our data support that BPA exposure increases the risk of developing cardiovascular diseases (CVDs) including atherosclerosis and its risk factors such as hypertension and diabetes. Furthermore, BPA exposure is also particularly harmful in pregnancy, promoting the development of hypertensive disorders during pregnancy. In summary, BPA exposure compromises human health, promoting the development and progression of CVDs and risk factors. Further studies are needed to clarify the human health effects of BPA-induced cardiotoxicity.

Relationship between exposure of alkylphenols in serum of pregnant women during early pregnancy and adverse birth outcomes

Alkylphenols are a type of endocrine disruptors, which are commonly found in personal care products, food, and water and are more harmful to the human body. To investigate the relationship between exposure of alkylphenols in serum of pregnant women during early pregnancy and adverse birth outcomes, a total of 2035 healthy pregnant women and their neonates were recruited in the birth cohort of Zhuang nationality in Guangxi from 2015 to 2018. The peripheral venous blood samples were collected from pregnant women in early pregnancy; the concentrations of nonylphenol (NP), 4-nonylphenol (4-N-NP), 4-tert-octylphenol (4-T-OP), and 4-n-octylphenol (4-N-OP) in serum were detected by ultra-performance liquid performance chromatography-tandem mass spectrometry (UPLC-MS). Binary logistic regression showed that NP [OR = 1.40 (95% CI: 1.00, 1.94)] was positively associated with preterm birth. Restricted cubic spline analyses showed that logNP and log4-T-OP had non-linearity associations with preterm birth (logNP: P_overall = 0.006, P_non-linear = 0.003; log4-T-OP: P_overall = 0.004, P_non-linear = 0.002). Multiple linear regression analysis showed that maternal serum concentration of NP was negatively associated with birth weight of perinatal infants (β = -14.68, 95% CI: -29.18, -0.19), which may be sensitive in male neonates (β = -26.18, 95% CI: -47.33, -5.02). The findings demonstrate that nonylphenol is a risk factor of preterm birth, and nonylphenol is negatively associated with the birth weight in male infants.

Pregnant Women and Endocrine Disruptors: Role of P2X7 Receptor and Mitochondrial Alterations in Placental Cell Disorders

In pregnant women, the lungs, skin and placenta are exposed daily to endocrine-disrupting chemicals (EDCs). EDCs induce multiple adverse effects, not only on endocrine organs, but also on non-endocrine organs, with the P2X7 cell death receptor being potentially the common key element. Our objective was first to investigate mechanisms of EDCs toxicity in both endocrine and non-endocrine cells through P2X7 receptor activation, and second, to compare the level of activation in lung, skin and placental cells. In addition, apoptosis in placental cells was studied because the placenta is the most exposed organ to EDCs and has essential endocrine functions. A total of nine EDCs were evaluated on three human cell models. We observed that the P2X7 receptor was not activated by EDCs in lung non-endocrine cells but was activated in skin and placenta cells, with the highest activation in placenta cells. P2X7 receptor activation and apoptosis are pathways shared by all tested EDCs in endocrine placental cells. P2X7 receptor activation along with apoptosis induction could be key elements in understanding endocrine placental and skin disorders induced by EDCs.

Fetoplacental vasculature as a model to study human cardiovascular endocrine disruption

Increasing evidence has associated the exposure of endocrine-disrupting chemicals (EDCs) with the cardiovascular (CV) system. This exposure is particularly problematic in a sensitive window of development, pregnancy. Pregnancy exposome can affect the overall health of the pregnancy by dramatic changes in vascular physiology and endocrine activity, increasing maternal susceptibility. Moreover, fetoplacental vascular function is generally altered, increasing the risk of developing pregnancy complications (including cardiovascular diseases, CVD) and predisposing the foetus to adverse health risks later in life. Thus, our review summarizes the existing literature on exposures to EDCs during pregnancy and adverse maternal health outcomes, focusing on the human placenta, vein, and umbilical artery associated with pregnancy complications. The purpose of this review is to highlight the role of fetoplacental vasculature as a model for the study of human cardiovascular endocrine disruption. Therefore, we emphasize that the placenta, together with the umbilical arteries and veins, allows a better characterization of the pregnant woman's exposome. Consequently, it contributes to the protection of the mother and foetus against CV disorders in life.

Pesticide exposure and genotoxic effects as measured by DNA damage and human monitoring biomarkers

Occupational pesticides exposure rises health concern due to genotoxicity and accumulation of pesticides in human biological matrices. Continuous and sublethal exposure to pesticides had been associated with oxidative stress, mutagenic and cell death. Exposure to pesticides exhibits increased level of DNA damage even if no detectable amounts of pesticides are seen in biological matrices by binding specific areas in the DNA. This interferes normal body systems and mutation in gene encoding specific activities which may lead to a wide range of cancer. Presence of pesticides compounds in human biological matrices had been evident from various studies. However, detection methods are complex and inconsistent, making it difficult to compare and generalize findings. This article provides insight into genotoxic effects, presence of pesticides and their metabolites in human biological matrices and the resultant health effects as measured by DNA damage, acetylcholinesterase (AChE) activity inhibition and other biomarkers of pesticides exposure.

UV-B Filter Octylmethoxycinnamate Alters the Vascular Contractility Patterns in Pregnant Women with Hypothyroidism

Increasing evidence relating the exposure and/or bioaccumulation of endocrine-disrupting compounds (EDCs) with cardiovascular system are arising. Octylmethoxycinnamate (OMC) is the most widely used UV-B filter and as EDC interacts with TH receptors. However, their effects on thyroid diseases during pregnancy remain unknown. The purpose of this work was to assess the short- and long-term effects of OMC on arterial tonus of pregnant women with hypothyroidism. To elucidate this, human umbilical artery (HUA) rings without endothelium were used to explore the vascular effects of OMC by arterial and cellular experiments. The binding energy and the modes of interaction of the OMC into the active center of the TSHR and THRα were analyzed by molecular docking studies. Our results indicated that OMC altered the contractility patterns of HUA contracted with serotonin, histamine and KCl, possibly due to an interference with serotonin and histamine receptors or an involvement of the Ca²⁺ channels. The molecular docking analysis show that OMC compete with T₃ for the binding center of THRα. Taken together, these findings pointed out to alterations in HUA reactivity as result of OMC-exposure, which may be involved in the development and increased risk of cardiovascular diseases.

4-Hexylphenol influences adipogenic differentiation and hepatic lipid accumulation in vitro

Finding the potential environmental obesogens is crucial to explain the prevalence of obesity and the related pathologies. Increasing evidence has showed that many chemicals with endocrine disrupting effects can disturb lipid metabolism. Whether 4-hexylphenol (4-HP), a widely-used surfactant and a potential endocrine disrupting chemical (EDC), is associated to influence adipogenesis and hepatic lipid accumulation remained to be elucidated. In this study, both the 3T3-L1 differentiation model and oleic acid (OA)-treated HepG2 cells were used to investigate the effects of 4-HP on lipid metabolism, and the underlying estrogen receptor (ER)-involved mechanism was explored using MVLN assay, molecular docking simulation and the antagonist test. The results based on lipid droplet staining and triglyceride accumulation assay showed that 4-HP treatment promoted the adipogenic differentiation of 3T3-L1 cells and increased hepatic cellular OA accumulation in exposure concentration-dependent manners. The study on the elaborated transcription networks indicated that 4-HP activated peroxisome proliferator-activated receptor γ (PPARγ) as well as the subsequent adipogenic gene program in 3T3-L1 cells. This chemical also induced the increase of OA uptake and decreases of de novo lipogenesis and fatty acid oxidation in HepG2 cells. The agonistic activity of 4-HP in triggering ER-mediated pathway was shown to correlate with its perturbation in lipid metabolism, as evidenced by the enhanced development of mature lipid-laden adipocytes and suppression of excessive hepatic lipid accumulation upon its co-treatment with ER antagonist. Altogether, these findings provide new insights into the potential health impacts of 4-HP exposure as it may relate to obesity and nonalcoholic fatty liver disease.

Fetal-Maternal Exposure to Endocrine Disruptors: Correlation with Diet Intake and Pregnancy Outcomes

Endocrine-disrupting chemicals (EDCs) are exogenous substances able to mimic or to interfere with the endocrine system, thus altering key biological processes such as organ development, reproduction, immunity, metabolism and behavior. High concentrations of EDCs are found in several everyday products including plastic bottles and food containers and they could be easily absorbed by dietary intake. In recent years, considerable interest has been raised regarding the biological effects of EDCs, particularly Bisphenol A (BPA) and phthalates, on human pregnancy and fetal development. Several evidence obtained on in vitro and animal models as well as by epidemiologic and population studies strongly indicated that endocrine disruptors could negatively impact fetal and placental health by interfering with the embryonic developing epigenome, thus establishing disease paths into adulthood. Moreover, EDCs could cause and/or contribute to the onset of severe gestational conditions as Preeclampsia (PE), Fetal Growth Restriction (FGR) and gestational diabetes in pregnancy, as well as obesity, diabetes and cardiovascular complications in reproductive age. Therefore, despite contrasting data being present in the literature, endocrine disruptors must be considered as a therapeutic target. Future actions aimed at reducing or eliminating EDC exposure during the perinatal period are mandatory to guarantee pregnancy success and preserve fetal and adult health.

Toxic Effects of Nonylphenol on Neonatal Testicular Development in Mouse Organ Culture

Nonylphenol (NP) is an alkylphenol that is widely used in chemical manufacturing. Exposure to this toxic environmental contaminant has been shown to negatively affect the reproductive system. Herein, we evaluated the toxicity of NP in mouse testes, while using in vitro organ culture. Mouse testicular fragments (MTFs), derived from five-day postpartum neonatal mouse testes, were exposed to different concentrations of NP (1-50 μM) for 30 days. The results showed that NP impaired germ cell development and maintenance. Furthermore, NP significantly downregulated the transcript levels of both undifferentiated and differentiated germ cell marker genes relative to those in controls. In particular, a high dose of NP (50 µM) led to complete germ cell depletion and resulted in spermatogenic failure, despite the presence of Sertoli and Leydig cells. In addition, the mRNA expression of steroidogenic enzymes, such as steroidogenic acute regulatory protein (STAR), Cytochrome P450 Family 11 Subfamily A Member 1 (Cyp11α1), Cytochrome P450 17A1 (Cyp17α1), and androgen receptor (AR), increased with increasing concentration of NP. Conversely, the expression of estrogen receptor alpha (ESR1) and Cytochrome P450 family 19 subfamily A member 1 (Cyp19α1) in NP-exposed MTFs decreased when compared to that of the control. Taken together, this study demonstrates that NP has a negative effect on prepubertal spermatogenesis and germ cell maintenance and it disrupts steroidogenesis and induces hormonal imbalance in MTFs.

Differential Toxicity of Alkylphenols in JEG-3 Human Placental Cells: Alteration of P450 Aromatase and Cell Lipid Composition

Alkylphenols (APs) are a diverse class of chemicals that can cross the placental barrier and interfere with embryonic and fetal development. This work investigates the comparative toxicity, ability to inhibit aromatase activity, and to alter the lipid composition of 10 alkylphenols in the human placenta choriocarcinoma cell line JEG-3. Among the selected APs, 4-dodecylphenol (DP), 4-heptylphenol (HP), and 4-cumylphenol (CP) showed the highest cytotoxicity (EC50: 18-65 µM). Aromatase inhibition was closely related to the hydrophobicity of APs. HP significantly induced the generation of reactive oxygen species (ROS) (43-fold), inhibited placental aromatase activity (IC50: 41 µM), and induced a general dose-dependent depletion of polyunsaturated lipids (10-20 µM), which were attributed to high levels of oxidative stress. In contrast, 2,4,6-tri-tert-butylphenol (TTBP) significantly induced the intracellular accumulation of triacylglycerides (TGs), whereas DP increased the synthesis of phosphatidylcholines (PCs) and TGs at the expense of diacylglycerides (DGs). Overall, this study evidences the different modes of action of alkylphenols in human placental JEG-3 cells, describes differential lipidomic fingerprints, and highlights DP, HP, CP, and TTBP as the ones that caused the most harmful effects.

Environmental Water Pollution, Endocrine Interference and Ecotoxicity of 4-tert-Octylphenol: A Review

4-tert-Octylphenol is a degradation product of non-ionic surfactants alkylphenol polyethoxylates as well as raw material for a number of industrial applications. It is a multimedia compound having been detected in all environmental compartments such as indoor air and surface waters. The pollutant is biodegradable, but certain degradation products are more toxic than the parent compound. Newer removal techniques from environmental waters have been presented, but they still require development for large-scale applications. Wastewater treatment by plant enzymes such as peroxidases offers promise in total removal of 4-tert-octylphenol leaving less toxic degradation products. The pollutant's endocrine interference has been well reported but more in oestrogens than in any other signalling pathways through which it is believed to exert toxicity on human and wildlife. In this paper we carried out a review of the activities of this pollutant in environmental waters, endocrine interference and relevance to its toxicities and concluded that inadequate knowledge of its endocrine activities impedes understanding of its toxicity which may frustrate current efforts at ridding the compound from the environment.

Distribution and fate of synthetic phenolic antioxidants in various wastewater treatment processes in Canada

Synthetic phenolic antioxidants (SPAs) are of emerging concern due to their potential environmental risks. However, the environmental occurrence and fate of SPAs are poorly understood. In this study, 13 SPAs were analyzed in 70 liquid and 21 solid samples from 12 wastewater treatment plants (WWTPs) in 2016 to investigate the distribution and composition of SPAs in different wastewater treatment processes in Canada. Wastewater samples were liquid-liquid extracted and biosolids were treated using ultrasonic assisted solvent extraction. SPAs were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry. The concentrations of total SPAs were in the ranges of 71-3193 ng L^-1 in influent, less than method quantification limits (MQLs)-520 ng L^-1 in effluent, and 479-4794 ng g^-1 in biosolids (dry weight (dw)). SPAs were effectively removed (median >75%) from the liquid stream in most WWTPs. In one aerated lagoon and two primary treatment sites, low removal efficiency (median -26%-43%) was observed for 4-tert-octylphenol (4-tOP). These results indicate that wastewater effluent is a vector for SPAs, including the endocrine disruptor 4-tOP, to aquatic environments. The mass balance approximation found major removal mechanisms are sludge sorption/separation and degradation. A preliminary risk assessment suggested that most SPAs in WWTP effluent were unlikely to pose ecotoxicological risks to aquatic organisms in the receiving waters. Future research should evaluate the environmental risks of SPAs associated with land application of biosolids and investigate the occurrence and fate of the degradation products of these contaminants.

Association of serum levels of 4-tertiary-octylphenol with cardiovascular risk factors and carotid intima-media thickness in adolescents and young adults

In the family of alkylphenolic compounds, 4-tertiary-Octylphenol (4-t-OP) is extensively used in many products. In animal and in vitro studies, 4-t-OP exposure has been linked to cardiovascular disease (CVD) risk factors; however, there are no previous human epidemiological studies. In this study, 886 subjects were recruited from a cohort of Taiwanese adolescents and young adults to study the relationship between serum levels of 4-t-OP, CVD risk factors, and common carotid artery intima-media thickness (CIMT). The geometric mean (SD) 4-t-OP concentration was 32.52 (1.71) ng/mL. We found that serum levels of 4-t-OP were negatively associated with markers of glucose homeostasis (insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β-cell function (HOMA-β)), z score of body mass index (BMI z score) and CIMT but were positively associated with lipid profiles (high density lipoprotein cholesterol (HDL-C), Apolipoprotein A1). A one-unit elevation in natural log-transformed 4-t-OP (ng/mL) was negatively correlated with CIMT (mm) (β = -0.029, SE = 0.003, P < 0.001) in multiple linear regression analyses. The relationship between 4-t-OP and CIMT remained the same in all subgroups or if bisphenol A (BPA) was considered a covariate. In this study, we observed that higher levels of 4-t-OP levels were negatively correlated with markers of glucose homeostasis, BMI z score, and CIMT; positively correlated with lipid profiles (HDL-C and apolipoprotein A) in this cohort. Future research on exposure to 4-t-OP and CVD risk factors is warranted.

Protective role of Ficus deltoidea against BPA-induced impairments of the follicular development, estrous cycle, gonadotropin and sex steroid hormones level of prepubertal rats

Ficus deltoidea is one of the well-known medicinal plants in Malaysia that is traditionally used by the Malay community to treat various ailments and for maintenance of female reproductive health. The objective of this study is to evaluate the potential protective roles of Ficus deltoidea against BPA-induced toxicity of the pituitary-ovarian axis in pre-pubertal female rats. In this study, four groups of pre-pubertal female Sprague Dawley rats were administered with the followings by oral gavage for a period of six weeks: NC (negative control- treated with vehicle), PC (positive control-treated with BPA at 10 mg/kg/BW), F (treated with Ficus deltoidea at 100 mg/kg/BW, then exposed to BPA at 10 mg/kg/BW) and FC (Ficus deltoidea control - treated with Ficus deltoidea at 100 mg/kg/BW). Daily vaginal smear, ovarian follicular development as well as gonadotropin and sexual-steroid hormone levels were determined. The findings showed that Ficus deltoidea demonstrated preventive role against BPA-induced toxicity on the ovaries. This was evident by the increased percentage of rats with normal estrous cycle, qualitatively reduced number of atretic follicles (as observed in histopathological examination) and normalization of the gonadotropins hormone (FSH) and sexual steroid hormone (progesterone) levels. In conclusion, Ficus deltoidea has the capability to prevent the effects of BPA toxicity in the hypothalamus-pituitary-gonadal axis of prepubertal female reproductive system, possibly due to its variety of phytochemical properties. Therefore, these findings strongly support the traditional belief that this medicinal plant is beneficial as daily dietary supplement for the maintenance of female reproductive health.

Endocrine-disrupting metabolites of alkylphenol ethoxylates - A critical review of analytical methods, environmental occurrences, toxicity, and regulation

Despite the fact that metabolites of alkylphenol ethoxylates (APEO) are classified as hazardous substances, they continue to be released into the environment from a variety of sources and are not usually monitored. Their wide use has led to an increase in the possible exposure pathways for humans, which is cause for alarm. Moreover, there is a lack of knowledge about the behaviour of these metabolites with respect to the environment and toxicity, and their biological effects on human health. The aim of this work is to give an overview of the APEO metabolites and their analysis, occurrences and toxicity in various environmental and human samples. APEO metabolites have adverse effects on humans, wildlife, and the environment through their release into the environment. Currently, there are some reviews available on the behaviour of alkylphenols in soil, sediments, groundwater, surface water and food. However, none of these articles consider their toxicity in humans and especially their effect on the nervous and immune system. This work summarises the environmental occurrences of metabolites of APEOs in matrices, e.g. water, food and biological matrices, their effect on the immune and nervous systems, and isomer-specific issues. With that emphasis we are able to cover most common occurrences of human exposure, whether direct or indirect.

In-capillary microextraction for direct mass spectrometry analysis of biological samples

Slug flow microextraction (SFME)-nanoESI was originally explored as a single-step sampling ionization method for MS analysis of biofluids. In this work, a comprehensive study and development of the SFME has been carried out. Revers-phase SFME was developed to analyze chemical compounds in oil samples. A three-phase SFME system was introduced as a suitable approach for analyzing polar compounds in biofluids. The impacts by the capillary inner diameter, solvent and sample properties were also investigated, leading the use of fused silica capillaries for performing SFME.

Oleuropein and hydroxytyrosol protect rats' pups against bisphenol A induced hypothyroidism

Bisphenol A (BPA) can disturb the endocrine system and the organs that respond to endocrine signals in organisms, indirectly exposed during prenatal and/or early postnatal life. The present study was designed to assess the protective effect of phenolic compounds from olive leaves against BPA induced thyroid dysfunction and growth perturbation in young rats during lactation. The BPA disrupting effect on thyroid function was investigated by measuring changes in plasma levels of thyroid hormones. Free triiodothyronine (FT3) and thyroxine (FT4) were decreased in young rats breast-fed from mothers treated with bisphenol A. This effect was associated with an increase in the plasma level of thyroid-stimulating hormone (TSH). The histological and immunohistochemical study of the thyroid gland revealed a disturbance in morphological structure and thyroid cells function. Thyroid dysfunction led to a disruption in the skeletal bone growth of young rats. In fact, the infrared microspectroscopic analysis and histological examination of femoral bone showed significant changes in their histoarchitecture associated with a perturbation in the mechanism of bone tissue mineralization. The administration of oleuropein or hydroxytyrosol in BPA treated lactating mothers improved the thyroid cells function by enhancing thyroid hormone levels. Moreover, these phenolics increased the body growth characterized by an amelioration in the structure and the microstructure of femoral bone tissue. HPLC analysis of rats-breast milk indicated the presence of oleuropein and hydroxytyrosol, which could contribute to the protective effect against bisphenol A induced hypothyroidism in pups rats.

Identification of Transmembrane Protease Serine 2 and Forkhead Box A1 As the Potential Bisphenol A Responsive Genes in the Neonatal Male Rat Brain

Perinatal exposure of Bisphenol A (BPA) to rodents modifies their behavior in later life. To understand how BPA modifies their neurodevelopmental process, we first searched for BPA responsive genes from androgen and estrogen receptor signaling target genes by polymerase chain reaction array in the neonatal male rat brain. We used a transgenic strain of Wistar rats carrying enhanced green fluorescent protein tagged to gonadotropin-inhibitory hormone (GnIH) promoter to investigate the possible interaction of BPA responsive genes and GnIH neurons. We found upregulation of transmembrane protease serine 2 (Tmprss2), an androgen receptor signaling target gene, and downregulation of Forkhead box A1 (Foxa1), an ER signaling target gene, in the medial amygdala of male rats that were subcutaneously administered with BPA from day 1 to 3. Tmprss2-immunoreactive (ir) cells were distributed in the olfactory bulb, cerebral cortex, hippocampus, amygdala, and hypothalamus in 3 days old but not in 1-month-old male rats. Density of Tmprss2-ir cells in the medial amygdala was increased by daily administration of BPA from day 1 to 3. Tmprss2 immunoreactivity was observed in 26.5% of GnIH neurons clustered from the ventral region of the ventromedial hypothalamic nucleus to the dorsal region of the arcuate nucleus of 3-day-old male rat hypothalamus. However, Tmprss2 mRNA expression significantly decreased in the amygdala and hypothalamus of 1-month-old male rats. Foxa1 mRNA expression was higher in the hypothalamus than the amygdala in 3 days old male rats. Intense Foxa1-ir cells were only found in the peduncular part of lateral hypothalamus of 3-day-old male rats. Density of Foxa1-ir cells in the hypothalamus was decreased by daily administration of BPA from day 1 to 3. Foxa1 mRNA expression in the hypothalamus also significantly decreased at 1 month. These results suggest that BPA disturbs the neurodevelopmental process and behavior of rats later in their life by modifying Tmprss2 and Foxa1 expressions in the brain.

Hepatic glucuronidation of 4-tert-octylphenol in humans: inter-individual variability and responsible UDP-glucuronosyltransferase isoforms

4-tert-Octylphenol (4-tOP) is an endocrine-disrupting chemical. It is mainly metabolized into glucuronide by UDP-glucuronosyltransferase (UGT) enzymes in humans. The purpose of this study was to assess inter-individual variability in and the possible roles of UGT isoforms in hepatic 4-tOP glucuronidation in the humans. 4-tOP glucuronidation activities in the liver microsomes and recombinant UGTs of humans were assessed at broad substrate concentrations, and kinetics were analyzed. Correlation analyses between 4-tOP and diclofenac or 4-hydroxybiphenyl activities in pooled and individual human liver microsomes were also performed. Typical CL_int values were 17.8 mL/min/mg protein for the low type, 25.2 mL/min/mg protein for the medium type, and 47.7 mL/min/mg protein for the high type. Among the recombinant UGTs (13 isoforms) examined, UGT2B7 and UGT2B15 were the most active of catalyzing 4-tOP glucuronidation. Although the K _m values of UGT2B7 and UGT2B15 were similar (0.36 and 0.42 µM, respectively), the CL_int value of UGT2B7 (6.83 mL/min/mg protein) >UGT2B15 (2.35 mL/min/mg protein). Strong correlations were observed between the glucuronidation activities of 4-tOP and diclofenac (a probe for UGT2B7) or 4-hydroxybiphenyl (a probe for UGT2B15) with 0.79-0.88 of Spearman correlation coefficient (r _s) values. These findings demonstrate that 4-tOP glucuronidation in humans is mainly catalyzed by hepatic UGT2B7 and UGT2B15, and suggest that these UGT isoforms play important and characteristic roles in the detoxification of 4-tOP.

Simultaneous determination of estrogenic odorant alkylphenols, chlorophenols, and their derivatives in water using online headspace solid phase microextraction coupled with gas chromatography-mass spectrometry

A simple online headspace solid-phase microextraction (HS-SPME) coupled with the gas chromatography-mass spectrometry (GC-MS) method was developed for simultaneous determination of trace amounts of nine estrogenic odorant alkylphenols and chlorophenols and their derivatives in water samples. The extraction conditions of HS-SPME were optimized including fiber selection, extraction temperature, extraction time, and salt concentration. Results showed that divinylbenzene/Carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was the most appropriate one among the three selected commercial fibers, and the optimal extraction temperature, time, and salt concentration were 70 °C, 30 min, and 0.25 g/mL, respectively. The developed method was validated and showed good linearity (R (2) > 0.989), low limit of detection (LOD, 0.002-0.5 μg/L), and excellent recoveries (76-126 %) with low relative standard deviation (RSD, 0.7-12.9 %). The developed method was finally applied to two surface water samples and some of these target compounds were detected. All these detected compounds were below their odor thresholds, except for 2,4,6-TCAS and 2,4,6-TBAS wherein their concentrations were near their odor thresholds. However, in the two surface water samples, these detected compounds contributed to a certain amount of estrogenicity, which seemed to suggest that more attention should be paid to the issue of estrogenicity rather than to the odor problem.

Determination of free and conjugated forms of endocrine-disrupting chemicals in human biological fluids by GC−MS

Background: Humans are exposed to hazardous substances including endocrine-disrupting chemicals (EDCs). These compounds have been associated with some diseases such as cancer and ascribed adverse effects on life-essential organs. Results: The method, which allows the determination of both free and conjugated forms of EDCs, involves the liquid–liquid extraction from the sample with ethyl acetate, followed by its preconcentration and clean-up by SPE in a continuous system for the subsequent determination by GC–MS. The proposed method affords very low LODs and RSD. Conclusion: This allowed its successful application to the determination of EDCs in human urine, blood and breast milk. The most frequently founded were methylparaben, ethylparaben, bisphenol A and triclosan.

Birth outcome measures and prenatal exposure to 4-tert-octylphenol

Exposure to 4-tert-octylphenol (tOP) has been linked with adverse health outcomes in animals and humans, while epidemiological studies about associations between prenatal exposure to tOP and fetal growth are extremely limited. We measured urinary tOP concentrations in 1100 pregnant women before their delivery, and examined whether tOP levels were associated with birth outcomes, including weight, length, head circumference and ponderal index at birth. tOP could be detected in all samples, and the median uncorrected and creatinine-corrected tOP concentrations were 0.90 μg/L (range from 0.25 to 20.05 μg/L) and 1.33 μg/g creatinine (range from 0.15 to 42.49 μg/g creatinine), respectively. Maternal urinary log-transformed tOP concentrations were significantly negatively associated with adjusted birth weight [β (g) = -126; 95% confidence interval (CI): -197, -55], birth length [β (cm) = -0.53; 95% CI:-0.93, -0.14], and head circumference [β (cm) = -0.30; 95% CI: -0.54, -0.07], respectively. Additionally, considering sex difference, these significant negative associations were also found among male neonates, while only higher maternal tOP concentrations were associated with a significant decrease in birth weight among female neonates. This study suggested significant negative associations between maternal urinary tOP concentrations and neonatal sizes at birth, and they differed by neonatal sex. Further epidemiological studies are required to more fully elaborate the associations between prenatal tOP exposure and birth outcomes.

Biological Tools to Study the Effects of Environmental Contaminants at the Feto-Maternal Interface

The identification of reproductive toxicants is a major scientific challenge for human health. Prenatal life is the most vulnerable and important time span of human development. For obvious ethical reasons, in vivo models cannot be used in human pregnancy, and animal models do not perfectly reflect human physiology. This review describes the in vitro test models representative of the human feto-maternal interface and the effects of environmental chemicals with estrogen-like activity, mainly bisphenol A and para-nonylphenol, with a particular emphasis on the effects at low, nontoxic doses similar to concentrations commonly detected in the population.

Low concentrations of Bisphenol A and para-Nonylphenol affect extravillous pathway of human trophoblast cells

Bisphenol A (BPA) and para-Nonylphenol (p-NP) are chemicals of industrial origin which may influence human reproductive health. The effects of these substances in the prenatal life is an important topic that is receiving greater attention in the developed countries. In this study, human trophoblast cells HTR-8/SVneo were exposed to BPA and p-NP (1 × 10(-15), 1 × 10(-13), 1 × 10(-11), 1 × 10(-9) and 1 × 10(-7) M) and incubated for 24, 48 and/or 72 h then, examined for the main physiological processes which characterize the extravillous trophoblast. Cell proliferation showed no changes while the processes of cell migration and invasion were both reduced by BPA and p-NP. For each chemical, the activity was higher at lower concentrations with a maximum activity between 1 × 10(-13) and 1 × 10(-11) M (p < 0.05 for 1 × 10(-9) and p < 0.001 for 1 × 10(-11) M). Co-culture studies with human umbilical cord endothelial cells (HUVEC) revealed that trophoblast/endothelial interaction was significantly reduced by p-NP at 1 × 10(-11) M. Moreover, both chemicals were inducing differentiation of HTR-8/SVneo toward polyploidy by the process of endoreduplication. The estrogen-receptor antagonist ICI significantly reduced p-NP action, while it had no effect on BPA treated cells. In conclusion, p-NP and BPA act on trophoblast cells altering key physiological processes in placenta development. The exact mechanism of action of the chemicals in human trophoblast still needs to be clarified.

The adverse effect of 4-tert-octylphenol on fat metabolism in pregnant rats via regulation of lipogenic proteins

Alkylphenols such as 4-tert-octylphenol (OP), nonylphenol, and bisphenol A are classified as endocrine-disrupting chemicals (EDCs). Digestion and metabolism of food are controlled by many endocrine factors, including insulin, glucagon, and estrogen. These factors are differentially regulated during pregnancy. The alteration of nutritional intake and fat metabolism may affect the maintenance of pregnancy and supplementation of nutrients to the fetus, and therefore can cause severe metabolic diseases such as ketosis, marasmus and diabetes mellitus in pregnant individuals. In this study, we examined the effects of OP on fat metabolism in pregnant rats. Ethinyl estradiol (EE) was also administered as an estrogenic positive control. In our results, rats treated with OP showed significantly reduced body weights compared to the control group. In addition, histological analysis showed that the amount of fat deposited in adipocytes was reduced by OP treatment. To study the mechanism of action of OP in fat metabolism, we examined the expression levels of fat metabolism-associated genes in rat adipose tissue and liver by real-time PCR. OP and EE negatively regulated the expression of lipogenic enzymes, including FAS (fatty acid synthase), ACC-1 (acetyl-CoA carboxylase-1), and SCD-1 (stearoyl-CoA desaturase-1). The levels of lipogenic enzyme-associated transcription factors such as C/EBP-α (CAAT enhancer binding protein alpha) and SREBP-1c (sterol regulatory element binding protein-1c) were also reduced in both liver and adipose tissue. In summary, these findings suggest that OP has adverse effects on fat metabolism in pregnant rats and inhibits fat deposition via regulating lipogenic genes in the liver and adipose tissue. The altered fat metabolism by OP may affect the nutrition balance during pregnancy and can cause metabolism-related diseases.

Global Assessment of Bisphenol A in the Environment: Review and Analysis of Its Occurrence and Bioaccumulation

Because bisphenol A (BPA) is a high production volume chemical, we examined over 500 peer-reviewed studies to understand its global distribution in effluent discharges, surface waters, sewage sludge, biosolids, sediments, soils, air, wildlife, and humans. Bisphenol A was largely reported from urban ecosystems in Asia, Europe, and North America; unfortunately, information was lacking from large geographic areas, megacities, and developing countries. When sufficient data were available, probabilistic hazard assessments were performed to understand global environmental quality concerns. Exceedances of Canadian Predicted No Effect Concentrations for aquatic life were >50% for effluents in Asia, Europe, and North America but as high as 80% for surface water reports from Asia. Similarly, maximum concentrations of BPA in sediments from Asia were higher than Europe. Concentrations of BPA in wildlife, mostly for fish, ranged from 0.2 to 13 000 ng/g. We observed 60% and 40% exceedences of median levels by the US Centers for Disease Control and Prevention's National Health and Nutrition Examination Survey in Europe and Asia, respectively. These findings highlight the utility of coordinating global sensing of environmental contaminants efforts through integration of environmental monitoring and specimen banking to identify regions for implementation of more robust environmental assessment and management programs.

QuEChERS-based approach toward the analysis of two insecticides, methomyl and aldicarb, in blood and brain tissue

QuEChERS has been widely utilized for the analysis of pesticides in produce, but it has not been as widely used in clinical test specimens, especially for smaller, sub-gram sample sizes. This study describes the application of a miniaturized QuEChERS methodology toward the analysis of two insecticides, methomyl and aldicarb, in guinea pig blood and brain tissue. Matrix effects and absolute recoveries were investigated for both analytes in the two matrices. While the matrix effects of methomyl in both matrices were minimal at most levels (i.e., from -20% to 20%), aldicarb experienced signal suppression under the described conditions (mean of -47%). However, the matrix effects were not cause for concern due to the sensitivity of the method and the use of matrix-matched standards. The precision and accuracy of the method were excellent over a range of concentrations that spanned three orders of magnitude. The limits of detection (LOD) for both carbamates were determined to be 0.1 ng mL^-1 in blood and 0.2 ng g^-1 in brain. Other validation parameters, such as linearity, accuracy, precision, and recovery, were also satisfactory in the blood and brain tissue. This method was demonstrated to be sensitive and reproducible, and it should be applicable to the analysis of a wide range of compounds of interest in sub-gram- and sub-milliliter-sized clinical and toxicology specimens.

Evidence that bisphenol A (BPA) can be accurately measured without contamination in human serum and urine, and that BPA causes numerous hazards from multiple routes of exposure

There is extensive evidence that bisphenol A (BPA) is related to a wide range of adverse health effects based on both human and experimental animal studies. However, a number of regulatory agencies have ignored all hazard findings. Reports of high levels of unconjugated (bioactive) serum BPA in dozens of human biomonitoring studies have also been rejected based on the prediction that the findings are due to assay contamination and that virtually all ingested BPA is rapidly converted to inactive metabolites. NIH and industry-sponsored round robin studies have demonstrated that serum BPA can be accurately assayed without contamination, while the FDA lab has acknowledged uncontrolled assay contamination. In reviewing the published BPA biomonitoring data, we find that assay contamination is, in fact, well controlled in most labs, and cannot be used as the basis for discounting evidence that significant and virtually continuous exposure to BPA must be occurring from multiple sources.

Nonylphenol in pregnant women and their matching fetuses: placental transfer and potential risks of infants

As the predominant environmental biodegradation product of nonylphenol (NP) ethoxylates and with proven estrogenic effects, NP is formed during the alkylation process of phenols. The purposes of this study were (1) to examine maternal and prenatal exposure to NP in Taiwan, (2) to determine the level of placental protection against NP exposure as well as the level of NP in breast milk, and (3) to assess the potential risk for breastfed newborns exposed to NP through the milk. Thirty pairs of maternal and fetal blood samples, placenta, and breast milk during the 1st and the 3rd months of lactation were collected. External NP exposures of these specimens were then analyzed by using high-performance liquid chromatography coupling with fluorescence detection. Next, the socio-demographics, lifestyle, delivery method, dietary and work history were collected using a questionnaire. In addition, the daily intake of NP from consuming breast milk in the 1st and 3rd months for newborns was studied through deterministic and probabilistic risk assessment methods. The geometric means and geometric standard deviation of NP levels in maternal blood, fetal cord blood, placenta, and breast milk in the 1st and 3rd months were 14.6 (1.7) ng/ml, 18.8 (1.8) ng/ml, 19.8 (1.9) ng/g, 23.5 (3.2) ng/ml, and 57.3 (1.4) ng/ml, respectively. The probabilistic percentiles (50th, 75th, and 95th) of daily intake NP in breast milk were 4.33, 7.79, and 18.39 μg/kg-bw/day in the 1st month, respectively, and were 8.11, 10.78, 16.08 μg/kg-bw/day in the 3rd month, respectively. The probabilistic distributions (5th, 25th, and 50th) of risk for infants aged 1 month old were 0.27, 0.64, and 1.15, respectively, and that for infants aged 3 month old were 0.31, 0.46, and 0.62, respectively. Through repeated exposure from the dietary intake of expectant mothers, fetuses could encounter a high NP exposure level due to transplacental absorption, partitioning between the maternal and fetal compartments. Daily NP intake via breast milk in three month-old babies exceeded the tolerable daily intake (TDI) of 5 µg/kg bw/day indicated a potential risk for Taiwan infants.

Bisphenol-A Concentrations from Leiomyoma Patients by LC/MS

The aim of this study is to investigate how many leiomyoma patients are exposed to bisphenol-A (BPA) , an endocrine disruptor, and whether the serum concentration of BPA is related to leiomyoma growth. Initially, 128 patients were divided into one control and three leiomyoma groups (mild, moderate and severe) according to the size of the leiomyomas. Serum BPA concentrations were measured by liquid chromatography and mass spectrometry (LC/MS) . Nearly two-thirds of leiomyoma patients were exposed to BPA and the range of BPA was from non-detection to 2.603 ng/ml. The mean BPA concentrations in the groups were 1.015 ± 0.775 ng/ml (control) , 0.774 ± 0.834 ng/ml (mild) , 1.261 ± 0.797 ng/ml (moderate) and 1.244 ± 0.860 ng/ml (severe) (p = 0.158) . After recombination into two group, Group 1 (control plus mild) vs. Group 2 (moderate plus severe) , higher level was found in Group 2 even with no statistical significance (p = 0.06) . In conclusion, about two-thirds of leiomyoma patients were exposed to BPA, but it may not have growth promoting effect on leiomyoma.

Associations of prenatal exposure to phenols with birth outcomes

Many phenols are known to mimic or antagonize hormonal activities and may adversely affect fetal growth. A study of 567 pregnant women was conducted to investigate the relationship between prenatal phenol exposure and birth outcomes, including birth weight, length, and gestational age. We measured the concentrations of bisphenol A, benzophenone-3, 4-n-octylphenol and 4-n-nonylphenol in maternal urine and examine their association with birth outcomes. Categories of urinary benzophenone-3 concentration were associated with decreased gestational age in all infants (p for trend = 0.03). Between middle and low exposure groups, we also found bisphenol A was negatively associated with gestational duration (βadjusted = -0.48 week; 95% confidence interval: -0.91, -0.05). After stratification by gender, we found the consistent results in infant boys with those in all infants, but we did not observe significant association for girls. In conclusion, we found prenatal phenol exposure was sex-specifically related to birth outcomes.

Exposure levels of environmental endocrine disruptors in mother-newborn pairs in China and their placental transfer characteristics

There is a growing concern about the potential health effects of exposure to various environmental chemicals during pregnancy and infancy. The placenta is expected to be an effective barrier protecting the developing embryo against some endocrine disruptors (EDs) circulating in maternal blood. The current study was designed to assess in utero exposure levels of non-persistent organic pollutants (non-POPs) and persistent organic pollutants (POPs) in Chinese newborns and potential role of placenta barrier against fetal exposure to these commonly-used environmental endocrine disruptors. A total of 230 newborn-mother pairs were enrolled during 2010–2011, 201 pairs of which were recruited from Shanghai, and the other 29 pairs came from Wenzhou. Maternal blood, cord blood, and meconium specimens were collected in the subject population from Shanghai and analyzed for non-POPs, including mono-2-ethylhexyl phthalate (MEHP), octylphenol (OP) and 4-nonylphenol (4-NP). A total of 19 polybrominated diphenyl ethers (PBDEs) congeners, which belong to POPs, were detected in maternal and cord blood specimens from the other 29 pairs. Fetal-maternal ratios (F-M ratios) and regression coefficients were presented to assess potential function of placenta on barricading the mother/fetal transfer of these EDs. Concentrations of the detected non-POPs in cord blood samples were approximately 20% lower than those in maternal blood, and regression coefficients of which were all over 0.80. In contrast, PBDEs levels in cord blood samples were significantly higher than those in maternal blood. MEHP levels in meconium were much higher than those in cord blood samples, and highly correlated. Therefore, observations demonstrated that the placental barrier slightly decreased the fetal exposure to most non-POPs, while PBDEs seemed to be totally transferred across the placenta and finally reached the fetus. For in utero exposure assessment of Di-2-ethylhexyl phthalate (DEHP), MEHP level in meconium may be a useful biomarker.

Simultaneous determination of bisphenol A, aflatoxin B1, ochratoxin A, and patulin in food matrices by liquid chromatography/mass spectrometry

RATIONALE

Bisphenol A has been widely used in plastic containers and this has raised safety concerns for fetuses, infants, and young children. Aflatoxin B1, ochratoxin A, and patulin are among the most toxic regulated mycotoxins found as contaminants in agricultural crops and animal products. To facilitate the analysis of these chemicals for regulatory purposes, we have developed an analytical method enabling their simultaneous detection in beverages and food products.

METHODS

Analytes were extracted from food matrices such as cereal, peanut butter, cereal-based baby formula and fruit juices, and enriched by solid-phase extraction (SPE). Samples were analyzed by liquid chromatography/mass spectrometry using negative electrospray ionization with selected reaction monitoring, and matrix-matched external calibration was used for quantitation.

RESULTS

The method was validated by analysis of five types of food and beverage samples fortified with different levels of these analytes. The SPE clean-up and matrix-matched external calibration were critical for the success of this method. The quantitation limits for these analytes ranged from 0.08 to 2.0 ppb, and the overall recoveries of the analytical method were within 66 to 127%.

CONCLUSIONS

This quantitative method provided several advantages including minimal sample pretreatment, rapid and simultaneous analyte determination, high sensitivity and confirmatory identification. This method could be applied to a variety of food and beverages matrices where bisphenol A and these three mycotoxins may be present in suspect food products. Published 2013. This article is a US Government work and is in the public domain in the USA.

Toxicity assessment on trophoblast cells for some environment polluting chemicals and 17β-estradiol

The identification of reproductive toxicants is a major scientific challenge for human health. We investigated the effects of a selected group of environmental polluting chemicals mostly provided with estrogenic activity on the human trophoblast cell lines BeWo and HTR-8/SVneo. Cells were exposed for 24h to various concentrations (from 0.1 pM to 1 mM) of atrazine (ATR), diethylstilbestrol (DES), para-nonylphenol (p-NP), resveratrol (RES) and 17 β-estradiol (E2) and assayed for cell viability and human beta-Chorionic Gonadotropin (β-hCG) secretion. Decrease of cell viability as respect to control, vehicle-treated, cultures was obtained for all chemicals in the concentration range of 1 μM-1 mM in both cell types. A parallel decrease of β-hCG secretion was observed in BeWo cells, at 1 μM-1 mM concentrations, with the only exception of ATR which caused an increase at concentrations up to 1mM. β-hCG release was also unexpectedly inhibited by ATR, DES, p-NP and RES at non-toxic (pM-nM) concentrations. These findings raise concern about the negative, potential effects of various environmental polluting chemicals on pregnancy success and fetal health.

Occurrence of bisphenol A in surface water, drinking water and plasma from Malaysia with exposure assessment from consumption of drinking water

This study investigated the level of bisphenol A (BPA) in surface water used as potable water, drinking water (tap and bottled mineral water) and human plasma in the Langat River basin, Malaysia. BPA was present in 93% of the surface water samples at levels ranging from below limit of quantification (LOQ; 1.3 ng/L) to 215 ng/L while six fold higher levels were detected in samples collected near industrial and municipal sewage treatment plant outlets. Low levels of BPA were detected in most of the drinking water samples. BPA in tap water ranged from 3.5 to 59.8 ng/L with the highest levels detected in samples collected from taps connected to PVC pipes and water filter devices. Bottled mineral water had lower levels of BPA (3.3±2.6 ng/L) although samples stored in poor storage condition had significantly higher levels (11.3±5.3 ng/L). Meanwhile, only 17% of the plasma samples had detectable levels of BPA ranging from 0.81 to 3.65 ng/mL. The study shows that BPA is a ubiquitous contaminant in surface, tap and bottled mineral water. However, exposure to BPA from drinking water is very low and is less than 0.01% of the tolerable daily intake (TDI).