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Background: Environmental phenols were recognized as endocrine disrupting chemicals (EDCs). However, their impact on childhood anthropometric measures and blood pressure (BP) is still inconclusive. Limited studies have simultaneously considered prenatal and childhood exposures in analyzing mixtures of phenols., Objective: We investigated the relationships between combined prenatal and childhood exposures (two periodic exposures) to phenol mixtures and anthropometric measure and BP, to further identify the vulnerable periods of phenol exposure and to explore the important individual contribution of each phenol., Methods: We analyzed 434 mother-child dyads from the Sheyang Mini Birth Cohort Study (SMBCS). The urinary concentrations of 11 phenolic compounds were measured using gas chromatography tandem mass spectrometry. Generalized linear regression models (GLMs) and hierarchical Bayesian Kernel Machine Regression (hBKMR) were used to examine the effects of individual phenolic compounds at each period and of two periodic exposures., Results: In the single-chemical analysis, prenatal or childhood exposure to specific phenols, especially Benzopheone-3 (BP3), 4-tert-Octylphenol (4-tOP), and Benzyl paraben (BePB) were associated with BMI z-scores (BAZ), Waist-to-height ratio (WHtR), and BP. In the hBKMR models, two periodic exposures to phenol mixtures had a U-shaped association with WHtR, primarily driven by childhood BePB exposure. Moreover, among the phenol mixtures analysis, childhood 4-tOP exposure was identified as the primary contributor to the positive association with diastolic BP. Concurrent exposure to phenol mixtures resulted in greater susceptibility., Conclusions: We found that prenatal and childhood exposure to phenol mixtures might influence childhood obesity and elevate blood pressure levels. Concurrent exposure to 4-tOP may be the primary driver of the positive associations with BP., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Zhijun Zhou reports financial support was provided by National Natural Science Foundation of China. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The extensive global use of neonicotinoid insecticides (NNIs) has led to widespread human exposure, necessitating the development of effective methods for large-scale biomonitoring. However, current methods are inadequate in simultaneously and accurately detecting various NNIs or their metabolites (m-NNIs). In this study, we aimed to establish a robust method using solid-phase extraction (SPE)-ultra high performance liquid chromatography tandem Q-Orbitrap high resolution mass spectrometry (UPLC-Q-Orbitrap HRMS) for the simultaneous determination of 12 NNIs and 6 m-NNIs in human urine. Samples were prepared using Oasis HLB 96 well plate with Isopropanol: methanol (7:3, v/v) as the elution solvent. The target compounds were separated using the Accucore RP-MS column and subsequently analyzed under parallel reaction monitoring mode. NTN32692 (m/z = 255.06433) was confirmed to be the specific metabolite of cycloxaprid for the further detection. Satisfactory recoveries (81.6-122.4 %) of the NNIs and m-NNIs were observed, with intra- (n = 3) and inter-day (n = 9) relative standard deviation (RSD) ranging from 0.8 % to 13.7 % and from 1.1 % to 18.6 %, respectively. Good linearity (R 2  > 0.99) was achieved for all analytes. The limits of detection (LODs) for all target analytes ranged from 0.01 ng/mL to 0.65 ng/mL. This method was applied to urine samples collected from 10 children recruited from an agricultural area in China. Our study provides an effective method to identify and assess human exposure to NNIs and their metabolites., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Triclosan is a broad-spectrum antimicrobial, and was thought to affect intrauterine development, but the mechanism remains unclear., Objective: To explore the association between prenatal triclosan exposure and birth outcomes., Methods: Based on 726 mother-child pairs from the Sheyang Mini Birth Cohort Study (SMBCS), we used the available (published) data of triclosan in maternal urines, the hormones including thyroid-related hormones, gonadal hormones in cord blood, and adipokines, trimethylamine-N-oxide (TMAO) and its precursors in cord blood to explore possible health effects of triclosan on birth outcomes through assessing different hormones and parameters, using Bayesian mediation analysis., Results: Maternal triclosan exposure was associated with ponderal index (β = 0.317) and head circumference (β = -0.172) in generalized linear models. In Bayesian mediation analysis of PI model, estradiol (β = 0.806) and trimethylamine (TMA, β = 0.164) showed positive mediation effects, while total thyroxine (TT4, β = -0.302), leptin (β = -2.023) and TMAO (β = -0.110) showed negative mediation effects. As for model of head circumference, positive mediation effects were observed in free thyroxine (FT4, β = 0.493), TMA (β = 0.178), and TMAO (β = 0.683), negative mediation effects were observed in TT4 (β = -0.231), testosterone (β = -0.331), estradiol (β = -1.153), leptin (β = -2.361), choline (β = -0.169), betaine (β = -0.104), acetyl-L-carnitine (β = -0.773)., Conclusion: The results indicated triclosan can affect intrauterine growth by interfering thyroid-related hormones, gonadal hormones, adipokines, TMAO and its precursors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Urinary para-nitrophenol (PNP), an exposure biomarker of ethyl parathion (EP) and methyl parathion (MP) pesticides, was still pervasively detected in the general population even after global restriction for years. And the concern whether there is an association of PNP level with child development of the nervous system is increasing. The current study aimed to evaluate the maternal urinary PNP concentrations during late pregnancy and the associations of PNP levels with cognitive and motor function of their children at the age of 2 years., Methods: 323 mother-child pairs from the Sheyang Mini Birth Cohort Study were included in the current study. Gas chromatography-tandem mass spectrometry was used to measure concentrations of PNP, the specific metabolite of EP and MP, in maternal urine samples during pregnancy. Developmental quotients (DQs) scores measured with Gesell Developmental Scales were employed to evaluate cognitive and motor function of children aged 2 years. Generalized linear models were performed to analyze the associations of PNP concentrations in pregnant women's urine samples with cognitive and motor function of their children., Results: Maternal PNP was detected in all urine samples with a median of 4.11 μg/L and a range from 0.57 μg/L to 109.13 μg/L, respectively. Maternal urinary PNP concentrations showed a negative trend with DQ of motor area [regression coefficient (β) = - 1.35; 95 % confidence interval (95 %CI): - 2.37, - 0.33; P < 0.01], and the children whose mothers were in the fourth quartile exposure group performed significantly worse compared to the reference group (β = - 1.11; 95 %CI: - 1.80, - 0.42; P < 0.01). As for average DQ score, children with their mothers' urinary PNP concentrations in the third quartile group had higher scores than those in the first quartile group (β = 0.39; 95 %CI: 0.03, 0.75; P = 0.04). In sex-stratified analyses, a negative trend between maternal urinary PNP concentrations and DQ scores in motor area of children was only observed in boys (β = - 1.62; 95 %CI: - 2.80, - 0.43; P < 0.01). Boys in the third quartile group had higher DQ average scores than those in the lowest quartile as reference (β = 0.53; 95 %CI: 0.02, 1.04; P = 0.04)., Conclusions: The mothers from SMBCS may be widely exposed to EP and/or MP, which were associated with the cognitive and motor function of their children aged 2 years in a sex-specific manner. Our results might provide epidemiology evidence on the potential effects of prenatal exposure to EP and/or MP on children's cognitive and motor function., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Declaration of Competing Interest The authors declare that they have no actual or potential competing financial interests., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Flurochloridone (FLC), a wildly used herbicide, could induce hepatotoxicity after long-term exposure to male rat, in addition to its reactive oxygen species (ROS)-dependent reproductive toxicity. The hepatotoxicity effect and mechanism was investigeted using 1, 10 and 100 μmol L -1 FLC treated BRL-3A liver cell in this study. The function of mitochondrial respiration, glycolysis rate and real time ATP production rate are determined by seahorse XF analyzer, and the bio-transformers of FLC, intermediates of TCA cycle and glycolysis, and related amino acids are determined and identified by [U- 13 C] Glucose metabolic flux technology based on UPLC-HRMS. The mRNA expression of cytochrome P450s and the key regulatory enzymes of glucose metabolism and γ- glutamyl cycle pathway. The protein expressions of protein kinase B (AKT) and glycogen synthase kinase-3 beta (GSK-3β) were determined. The results show dechlorination and glutathione (GSH) conjugate products of FLC are predominant bio-transformmers after 24 h treatment in BRL-3A cell. FLC could enhance glycolysis function and inhibit mitochondrial aerobic respiratory, which is accompanied by the decreased total ATP level and ATP produced rate. Increased glucose-6-phosphate, fructose-6-phosphate, pyruvate and lactate levels, and elevated level of GSH and its precursor 5-glutamate-cysteine (γ-Glu-Cys) are observed in FLC treated cells, which indicates that energy metabolism dysfunction and GSH accumulation could be potentially mediated by activating γ- Glutamyl cycle pathway. Conclusively, FLC induced hepatotoxicity could be potentially related to some free radical reactions, including inhibiting mitochondrial function, glucose metabolism via glycolysis, regulating γ- glutamyl cycle pathway to promote reactive oxygen species (ROS) level, and then induced cell apoptosis by inhibiting AKT/GSK-3β signal., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

In addition to maintaining bile acid, cholesterol and glucose homeostasis, farnesoid X receptor (FXR) also regulates fatty acid β-oxidation (FAO). To explore the different roles of hepatic and intestinal FXR in liver FAO, FAO-associated metabolites, including acylcarnitines and fatty acids, and FXR target gene mRNAs were profiled using an integrated metabolomic and transcriptomic analysis in control (Fxr fl/fl ), liver-specific Fxr-null (Fxr ΔHep ) and intestine-specific Fxr-null (Fxr ΔIE ) mice, treated either with the FXR agonist obeticholic acid (OCA) or vehicle (VEH). Activation of FXR by OCA treatment significantly increased fatty acyl-CoA hydrolysis (Acot1) and decreased FAO-associated mRNAs in Fxr fl/fl mice, resulting in reduced levels of total acylcarnitines and relative accumulation of long/medium chain acylcarnitines and fatty acids in liver. Fxr ΔHep mice responded to OCA treatment in a manner similar to Fxr fl/fl mice while Fxr ΔIE mice responded differently, thus illustrating that intestinal FXR plays a critical role in the regulation of hepatic FAO. A significant negative-correlation between intestinal FXR-FGF15 and hepatic CREB-PGC1A pathways was observed after both VEH and OCA treatment, suggesting that OCA-induced activation of the intestinal FXR-FGF15 axis downregulates hepatic PGC1α signaling via inactivation of hepatic CREB, thus repressing FAO. This mechanism was confirmed in experiments based on human recombinant FGF19 treatment and intestinal Fgf15-null mice. This study revealed an important role for the intestinal FXR-FGF15 pathway in hepatic FAO repression., (Copyright © 2021. Published by Elsevier B.V.)

Aims: Investigate the effect of renal denervation (RDN) on chronic intermittent hypoxia (CIH) induced high blood pressure (BP) and cardiac injury, and explore whether the effect is associated with gut microbiota alteration and its product, trimethylamine N-oxide (TMAO)., Materials and Methods: Thirty six-week-old Sprague Dawley male rats were randomly divided into three groups: Control, CIH (20 cycles h -1 , 7-8% at nadir, 8 h.day -1 for 6 weeks) and RDN group. Fecal samples, serum and heart tissue were collected at week 6. 16S rRNA gene sequencing was performed in fecal samples., Key Findings: Systolic BP in CIH group was significantly elevated compared with Control (164 ± 3 vs. 143 ± 4 mmHg, p = 0.004), while RDN treatment evidently reduced elevated systolic BP (133 ± 5 vs. 164 ± 3 mmHg, p < 0.001). CIH group featured significant cardiac perivascular fibrosis, compared with Control, whereas RDN treatment effectively attenuated perivascular fibrosis. Principal component analysis showed that CIH rats, but not RDN group were noticeably separated from Control. At phyla level, the structure of the biological community of RDN rats converged with that of control rats, which was apparently different in comparison to CIH rats. TMAO levels in the three groups were not significantly different., Significance: RDN exerts beneficial effect on BP control and perivascular fibrosis in rats exposed to CIH. This effect is associated with its ability to revert the already skewed gut microbiota caused by CIH, but is not via regulation of TMAO., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Environmental phenols, bisphenol A (BPA), triclosan (TCS), and benzophenone-3 (BP-3), are known as emerging endocrine-disrupting chemicals; however, their impacts on thyroid hormones and children's neurobehaviors are still unclear., Objectives: We aimed to examine the associations of prenatal and childhood exposure to phenols with neonatal thyroid function and childhood behavioral problems aged 10 years., Methods: A total of 386 mother-singleton pairs were included from Sheyang Mini Birth Cohort Study (SMBCS), a longitudinal birth cohort in China. We quantified urinary BPA, TCS and BP-3 concentrations in maternal and 10-year-old children's urine samples using gas chromatography tandem mass spectrometry and thyroid function parameters in cord serum samples. Caregivers completed the Strength and Difficulties Questionnaire (SDQ) for their children at 10 years of age. Multivariable linear regression models and logistic regression models were applied to estimate associations of urinary phenol concentrations with thyroid hormones and risks of children's behavioral problems, respectively., Results: The median values of urinary BPA, TCS and BP-3 concentrations for pregnant women were 1.75 μg/L, 0.54 μg/L and 0.37 μg/L, while 1.29 μg/L, 6.64 μg/L and 1.39 μg/L for children, respectively. Maternal urinary BPA concentrations were in associations with 1.00% [95% confidence interval (CI): 0.20%, 1.92%] increases in cord serum FT4 concentrations and significantly associated with increased risks of total difficulties [odds ratio (OR): 1.45, 95% CI: 1.07, 1.97], while maternal urinary levels of BP-3 were significantly related to poorer prosocial behaviors (OR: 1.58, 95% CI: 1.04, 2.39) of children at 10 years of age. In sex-stratified analyses, maternal urinary BPA concentrations were related to increased total difficulty subscales only in boys., Conclusions: The findings indicated that higher prenatal urinary BPA concentrations were associated with increased risks of total difficulties, especially in boys and maternal urinary BP-3 concentrations were related to poorer prosocial behaviors at 10 years., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Triptolide, a major active component of Triptergium wilfordii Hook. f, is used in the treatment of autoimmune disease. However, triptolide is associated with severe adverse reactions, especially hepatotoxicity, which limits its clinical application. To examine the underlying mechanism of triptolide-induced liver injury, a combination of dose- and time-dependent toxic effects, RNA-seq and metabolomics were employed. Triptolide-induced toxicity occurred in a dose- and time-dependent manners and was characterized by apoptosis and not necroptosis. Transcriptomics profiles of the dose-dependent response to triptolide suggested that PI3K/AKT, MAPK, TNFα and p53 signaling pathways were the vital steps in triptolide-induced hepatocyte apoptosis. Metabolomics further revealed that glycerophospholipid, fatty acid, leukotriene, purine and pyrimidine metabolism were the major metabolic alterations after triptolide exposure. Finally, acylcarnitines were identified as potential biomarkers for the early detection of triptolide-induced liver injury., Competing Interests: Declaration of Competing Interest The authors report no declarations of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Parabens, suspected as endocrine-disrupting chemicals, are nearly ubiquitous in the human body and exposure to these chemicals during pregnancy may disrupt thyroid hormones homeostasis and even affect fetal growth, although the impacts are still unclear., Objectives: We aimed to estimate associations of maternal urinary paraben concentrations with cord serum thyroid hormones and birth weight., Methods: A subset of 437 mother-newborn pairs were included from a prospective birth cohort with five parabens quantified in maternal urine and seven thyroid function indicators measured in cord serum samples. Multivariable linear regression models and elastic net regression (ENR) models were applied to explore associations between individual and mixtures of prenatal urinary paraben concentrations and thyroid hormones and birth weight, respectively., Results: Maternal urinary ethyl-paraben (EtP) concentrations were associated with increased cord serum total triiodothyronine levels (TT3) [percent change: 1.51%; 95% confidence interval (CI): 0.20%, 2.74%; p=0.017]. Urinary propyl-paraben (PrP) levels predicted higher thyroid peroxidase antibodies (percent change: 4.19%, 95%CI: 0.20%, 8.44%; p=0.041). Maternal urinary EtP and butyl-paraben (BuP) concentrations were significantly positively associated with birth weight [regression coefficient, (β)=40.9g, 95%CI: 3.99, 76.6; p=0.030; β=62.1g, 95%CI: 8.70, 115; p=0.023, for EtP and BuP, respectively]. In sex-stratified analyses, positive relationship between EtP levels and birth weight was observed in boys. Urinary EtP concentrations predicted higher TT3 levels in cord serum samples, assessing parabens as a chemical mixture with ENR models., Conclusions: Prenatal exposure to parabens may affect thyroid hormone indicators with increased serum TT3 levels and associate with higher birth weight, especially in boys. The underlying biological mechanisms and effects of prenatal paraben exposures on disruption of thyroid function homeostasis and potential impacts of childhood growth and development needed to be further investigated., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Carbamate pesticides exposure have been linked with adverse health effects during developmental period. Based on 377 mother-child pairs from Sheyang Mini Birth Cohort Study, the present study aimed to assess carbofuranphenol exposure of three-year-old children and explore the associations between prenatal or postnatal carbofuranphenol exposures and neurodevelopmental indicators., Methods: Urinary carbofuranphenol concentrations were measured by gas chromatography-tandem mass spectrometry. Neural developmental quotient (DQ) of children was evaluated using Gesell Developmental Schedules. Generalized linear models were used to examine the associations between carbofuranphenol concentrations and neurodevelopment., Results: Geometric mean, geometric standard deviation, median, inter quartile range of postnatal urinary carbofuranphenol concentrations were 0.653 μg/L, 9.345 μg/L, 0.413 μg/L, 0.150-1.675 μg/L, respectively. Postnatal carbofuranphenol level showed negatively significant trend in language DQ [beta (β) = -0.121; 95% confidence interval (95% CI): 0.212, -0.031; p value (p) = 0.008] and total average DQ (β = -0.059, 95% CI: 0.115, -0.003; p = 0.035). Prenatal carbofuranphenol level showed negative correlations with children's adaptive DQ (β = -0.755; 95% CI: 1.257, -0.254; p = 0.003), social DQ (β = -0.341; 95% CI: 0.656, -0.027; p = 0.032) and total average DQ (β = -0.349; 95% CI: 0.693, -0.005; p = 0.047)., Conclusion: The results of the present study supposed children in agricultural region of China are widely exposed to carbamate pesticides, and both prenatal and postnatal exposure to carbamate pesticides may lead to neurodevelopmental effect., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Simple metabolome and lipidome sample preparation procedures involving two successive extractions using small pieces of tissue, and a subsequent metabolite identification (MetID) strategy were developed. The sample preparation can significantly circumvent incomplete analysis due to insufficient amounts of tissue as a result of splitting into several aliquots for multiple measurements, with advantages over the similar previously reported methods in metabolite coverage, extraction efficiency, method robustness and friendly experimental operation. A MetID strategy, based on the integration of MS information mining (including adduct ions, in-source CID, MS information from both ESI (+) and ESI (-), characteristic fragmentation ions (CFIs), constant neutral losses (CNLs) and multimers) and in silico MS simulation, was demonstrated. A large number of adduct ions (83 features), in-source CID (123 features), ESI (+/-) ionization (20 features), CFIs& CNLs (more than 120 features) and multimers (17 features) were mined by manually or in silico recognition/filtering, which provide the most suspicious structures for subsequent in silico MS simulation. The unknown features presented the same score distribution as the known (83 features) features with scores ≥25% (geomean score: 52%) and with satisfactory match for the main ions of interest. The MS/MS noise and fragment ions of coeluted quasi-molecular ions of interest are the main reason for the low score in the simulation. Manual check/evaluation is always suggested for the simulation with a score less than 50%. This strategy presents satisfactory performance with 2.5 times more metabolites structurally characterized compared with that of the traditional method based on accurate-mass-based MS and MS/MS library matching. This strategy would be useful for potentially identifying metabolites without available MS/MS information in the library., (Copyright © 2018. Published by Elsevier B.V.)

Exposure to carbamates has been linked with adverse health effects on developmental period. This study aimed to monitor exposure to carbofuranphenol of pregnant women from Sheyang Birth Cohort and investigate associations between prenatal exposure to carbofuranphenol and birth outcomes. During June 2009 to January 2010, 1100 pregnant women living in Sheyang County participated in our study and donated urine sample. Urinary carbofuranphenol concentration was measured by gas chromatography-tandem mass spectrometry. Associations between urinary carbofuranphenol levels and infant birth outcomes were assessed by generalized linear models. Urinary carbofuranphenol concentrations varied from 0.01 to 395.40μg/L (0.01-303.93μg/g for creatinine adjusted), the geometric mean, median and inter quartile range are 0.81μg/L (1.28μg/g cr), 0.80μg/L (1.23μg/g cr) and 0.27-2.20μg/L (0.47-3.11μg/g cr), respectively. No statistically significant association between maternal urinary carbofuranphenol levels and birth outcomes was found in total infants and female infants. In male neonates, carbofuranphenol level was significantly associated with head circumference (b=-0.226; 95% confidence interval: -0.411, -0.041; P=0.01) and ponderal index (b=0.043, 95% CI: 0.004, 0.083; P=0.03). These findings suggested that the pregnant women were generally exposed to carbofuranphenol and prenatal exposure to carbofuranphenol might have adverse effects on fetal development., (Copyright © 2017 Elsevier B.V. All rights reserved.)

To investigate the effects of renal denervation (RDN) on comprehensive cardiac and renal fibrosis in cardiomyopathy. Five weeks after successful transverse aortic constriction (TAC)-induced cardiomyopathy model building, Sprague-Dawley rats were randomly assigned to three groups: (1) RDN, (2) sham, and (3) losartan. Sham TAC rats served as control group. Compared with control, TAC groups showed a significant decrease in left ventricle ejection fraction and increase in ventricular septum thickness and left atrium diameter on echocardiography after 5 weeks. At 10 weeks post-TAC, venous blood samples were collected for fibrosis biochemical assay. Heart and kidney samples were also harvested for fibrosis pathophysiological detection. Cardiac and renal fibrosis quantity results showed that, compared with sham group, collagen volume fraction was significantly decreased in RDN group more than in losartan group. Biochemical parameters such as tumor necrosis factor α, aldosterone, and B-type natriuretic peptide levels as well as biomarkers for fibrosis such as procollagen type I N-terminal propeptide and procollagen type III N-terminal propeptide concentrations were significantly decreased in RDN group in comparison with sham. In addition, compared with sham group, left ventricle tissue protein expression of transforming growth factor-β1 and angiotensin II type I receptor was downregulated, and angiotensin-converting enzyme 2 was upregulated in RDN but not in losartan group. RDN significantly attenuates cardiac and renal fibrosis in cardiomyopathy. Differing from losartan, which only has angiotensin II type I receptor inhibition effects, RDN comprehensively suppresses cardiac and renal fibrogenesis through multiple pathways., (Copyright © 2016 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.)

Bromophenols (BrPs), as the metabolites of PBDEs, would be the potential exposure markers for human biomonitoring (HB) of PBDEs in urine. An analytical method using solid-phrase extraction (SPE) and gas chromatography coupled to tandem mass spectrometer (GC-MS/MS) was developed and validated for simultaneous determination of nineteen BrPs in human urine. The method detection limits (MDLs) were below 23pgmL(-1), with recovery ranged from 63% to 133% and inter-day repeatability ranged from 3% to 11% for the majority of target analytes. This method was applied in a pilot study and 2-Bromophenol (2-BrP), 4-Bromophenol (4-BrP), 2,4-Dibromophenol (2,4-DBP) and 2,4,6-Tribromophenol (2,4,6-TBP) as the predominant analytes were detected in human urine samples collected from the general population. Among the four detected analytes, 2-BrP and 4-BrP as the mono-brominated BrP congeners were firstly reported. To our knowledge, it is the first study covering all BrP congeners (from mono-brominated to penta-brominated, totally 19 congeners) in human urine. Therefore, this study is very useful for profiling urinary BrPs and discovering potential relationship between urinary BrPs and human internal exposure to PBDEs. The mechanism of fragmentation pathway of silanized BrPs was firstly illustrated in this study., (Copyright © 2016 Elsevier B.V. All rights reserved.)

It is of great interest to develop strategic methods to enable chemicals' metabolites to be accurately and rapidly screened and identified. To screen and identify a category of metabolites with distinct isotopic distribution, this study proposed a generic strategy using in silico metabolite prediction plus accurate-mass-based isotopic pattern recognition (AMBIPR) and library identification on the data acquired via the data dependent MS/MS scan of LC-Q Exactive Orbitrap mass spectrometry. The proposed method was evaluated by the analysis of flurochloridone (FLC) metabolites in rat urine sample collected from toxicity tests. Different from the traditional isotopic pattern recognition (IPR) approach, AMBIPR here was performed based on the potential metabolites predicted via in silico metabolite prediction tools. Thus, the AMBIPR treated FLC data was only associated with FLC metabolites, consequently not only avoiding great efforts made to remove FLC-unrelated information and reveal FLC metabolites, but also increasing the percent of positive hits. Among the FLC metabolite peaks screened using AMBIPR, 87% of them (corresponding 97 metabolites and 49 biotransformation) were successfully identified via multiple MS identification techniques packaged in an established FLC's metabolites library based on Mass Frontier. Noteworthy, 34 metabolites (89%) were identified without distinct naturally isotopic distribution. The universal strategic approach based on background subtraction (BS) and mass defect filtering (MDF) was used to evaluate the AMBIPR and no more false positive and negative metabolites were detected. Furthermore, our results revealed that AMBIPR is very effective, inherently sensitive and accurate, and is easily automated for the rapidly screening and profiling chemicals related metabolites., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A new method was developed to determine polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in fishery and aquaculture products. Samples were extracted by an accelerated solvent extraction system and cleaned up by sequential solid phase extraction (SPE) including dispersive SPE (D-SPE) and tandem SPE. PBDEs and PCBs were analyzed by a large-volume injection gas chromatography triple quadrupole mass spectrometry (LVI-GC-QqQ-MS/MS). Good linearity (R(2)≥0.9958) was achieved. Method detection limits (MDLs) were 0.16-3.3pgg(-1) (wet weight, ww) for PBDEs and 0.13-0.97pgg(-1)ww for PCBs. Mean recoveries were 60-140% with relative standard deviations (RSDs) of less than 20% in weever fish, scallop and shrimp samples spiked at a lower level of 13-31pgg(-1)ww and a higher level of 50-125pgg(-1)ww. Certified reference materials were analyzed with acceptable results. The method reduced solvent consumption, analytical time and labor, and is suitable for the routine analysis of PBDEs and PCBs in fishery and aquaculture products., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this study, a method was developed to determine 45 selected pesticides (of different chemical families) in fruit and vegetable (including apple, spinach and cucumber). Samples were extracted using an improved QuEChERS method with salting out and phase separation in two steps. The target pesticides in concentrated extracts were analyzed by an on-line gel permeation chromatography-gas chromatography/mass spectrometer (online-GPC-GC/MS). Online GPC effectively removed matrix interferences and greatly improved the method sensitivity, recoveries and automation. Method limits of quantification were 10 ng/g for uniconazole and metalaxyl, and 5 ng/g for other 43 target analytes. In three fruit and vegetable matrices each spiked with 45 pesticides (0.01 μg/g), mean recoveries ranged from 80 to 118% for most of the tested pesticides except for profenofos (77% in apple) and chlorpyrifos (68% in apple and 75% in cucumber), with relative standard deviations (RSDs) of less than 14%. The results of the proficiency testing showed that the method is very successful in measuring the certified pesticides with less than 1.3 of the absolute value of Z-score. This method has been applied for routinely monitoring pesticides in fresh fruit and vegetable., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A quantitative method that requires only a small volume (50μL) of blood has been developed for the determination of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). Target analytes in both plasma sample (DBSV) and dried blood spot (DBS) were analyzed by a gas chromatography/high resolution mass spectrometer (GC/HRMS). Measurements of standard reference materials by the developed method were in agreement with those certified values. Linear correlation coefficients were found to be 0.9984 and 0.9965 for DBS and DBSV analysis, respectively. Other analytical criteria, such as limits of detection, recoveries, precision, accuracy and linearity of the proposed method are also reported. From recovery studies, the addition of formic acid to the extraction solvent was found to be effective in extracting PBDEs and PCBs from filter paper. The PBDE and PCB levels in spiked DBS were monitored at room temperature for up to 30 days and the variations of target analytes were found to be insignificant. Our results suggest that DBS sampling technique is feasible for PBDE and PCBs biomonitoring in human population., (Published by Elsevier B.V.)