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1.
Environ Pollut ; : 115121, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33139099

RESUMO

Polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), as the secondary environmental pollutants of the widely used brominated flame retardants (BFRs), possess the similar physicochemical and toxic properties as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). However, studies on human body exposure to them are extremely limited. In this study, forty human milk samples collected in Shanghai were measured for 13 PBDD/F congeners using gas chromatography-high resolution mass spectrometry (GC-HRMS), to investigate their exposure level and characteristics, potential source and corresponding health risks to breastfed infants. The results showed no PBDDs but three PBDF congeners including 2,3,7,8-TBDF, 1,2,3,4,6,7,8-HpBDF and OBDF (mean concentration (detection rates) are 3.2 pg/g (72.5%), 9.5 pg/g (100%) and 28 pg/g (67.5%), respectively) were detected. The average toxic equivalent quantity (TEQ, 0.42 pg/g lw) presented the highest concentration level compared to other regions reported. The contribution of PBDFs to the total TEQ of PBDD/Fs and PCDD/Fs is 6.8%. The correlation between PBDD/Fs and age or dietary habits was not observed, which normally existed in their chlorinated analogues-PCDD/Fs. Significant correlations were observed between PBDFs and highly brominated polybrominated diphenyl ethers (PBDEs) (especially for BDE 183 and BDE 209). The correlation between PCDD/Fs and PBDFs was not observed except 2,3,7,8-TBDF. The high PBDFs exposure in Shanghai may originate from the emission of PBDEs and/or non-PBDE BFRs in environment, according to the consistency of the environmental data previously reported. The average estimated dietary intakes (EDI) for breastfed infants is 2.0 pg TEQ/kg·bw/day (0.13-13 pg TEQ/kg·bw/day), within the range of the tolerable daily intake (TDI) for TCDD (1-4 pg TEQ/kg·bw/day) suggested by the World Health Organization (WHO). However, given the high toxicity of PBDD/Fs, the potential health risks of these pollutants for breastfed infants should be of concern.

2.
Chemosphere ; 271: 129447, 2020 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-33476874

RESUMO

Computational QSAR models have gradually been preferred for retention time prediction in data mining of emerging environmental contaminants using liquid chromatography coupled with mass spectrometry. Generally, the model performance relies on the components such as machine learning algorithms, chemical features, and example data. In this study, we evaluated the performances of four algorithms on three feature sets, using 321 and 77 pesticides as the training and validation sets, respectively. The results were varied with different combinations of algorithms on distinct feature sets. Two strategies including enhancing the complexity of chemical features and enlarging the size of the training set were proved to improve the results. XGBoost, Random Forest, and lightGBM algorithms exhibited the best results when built on a large-scale chemical descriptors, while the Keras algorithm preferred fingerprints. These four models have comparable prediction accuracies that at least 90% of pesticides in validation set can be successfully predicted with ΔRT <1.0 min. Meanwhile, a blended prediction strategy using average results from four models presented a better result than any single model. This strategy was used for assisting identification of pesticides and pesticide transformation products in 120 strawberry samples from a national survey of food contamination. Twenty pesticides and twelve pesticide transformation products were tentatively identified, where all pesticides and two pesticide transformation products (bifenazate diazene and spirotetramat-enol) were confirmed by standard materials. The outcome of this study suggested that retention time prediction is a valuable approach in compound identification when integrated with in silico MS2 spectra and other MS identification strategies.

3.
Ecotoxicol Environ Saf ; 184: 109609, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31518828

RESUMO

Carbazole and halogenated carbazoles have been widely detected throughout the environment in soil, river deposits, and lake sediments. Human exposure to these compounds may occur through inhalation, drinking water, dietary intake and/or skin contact, and exposure levels in the body may be evaluated by measuring them in serum or blood. This paper reports the method development and validation for the analysis of carbazole and 11 halogenated carbazoles in human blood and/or serum samples. A small sample size of 100 µL of blood or serum was employed for the analysis. The samples were prepared through salting-out liquid-liquid extraction (LLE) by using hexane/ethyl acetate (4:1, v/v) as the extraction solvent and aqueous MgSO4 (37.5 wt%) as the salting-out regent, respectively. Sample analysis was performed using gas-chromatography (GC) coupled with a tandem mass spectrometer (MS/MS) in an electron impact (EI) mode. The developed method demonstrated low detection limits in the range of 0.02-0.27 ng/mL, intra-day accuracy ranging from 81.2% to 125%, and inter-day accuracy from 91.0% to 117%. The intra- and inter-day precisions, calculated by relative standard deviations (RSDs), were in the ranges of 1.0-16.0% and 1.8-16.4%, respectively. The developed method was applied to the analysis of 50 human serum samples collected from pregnant women in Southern California in 2012. Low concentrations of carbazole were measured in 18 samples, while halogenated carbazoles were not detected in any of the samples.


Assuntos
Análise Química do Sangue/métodos , Carbazóis/sangue , Exposição Ambiental/análise , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem , California , Feminino , Halogenação , Humanos , Limite de Detecção , Gravidez
4.
Environ Pollut ; 248: 304-311, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30802744

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants with a number of them being carcinogenic. One of the approaches to assess human exposure to PAHs is to measure their urinary metabolites, monohydroxyl polycyclic aromatic hydrocarbons (OH-PAHs), with a method allowing for high throughput and short turn-around time. We developed a method to quantify nine urinary OH-PAHs by using supported liquid phase extraction (SLE) and isotope dilution gas chromatography tandem mass spectrometry (GC-MS/MS). SLE demonstrated advantages over the traditionally used liquid-liquid extraction techniques. The target analytes with spiked deuterated and 13C-labeled internal standards were extracted from urine by SLE after enzymatic cleavage of the glucuronide and sulfate conjugates. The extracted analytes were then derivatized with N-Methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA), and analyzed by GC-MS/MS. Six solvent mixtures were evaluated as the SLE extraction solvent, and pentane:chloroform (7:3, v/v) was selected due to its best overall analytical performance. Method detection limits for the 9 analytes ranged from 2.3 to 13.8 pg/mL. Precision and accuracy were satisfactory. SLE and internal isotope labeled standard combination reduced matrix effect effectively. This new method using SLE sample preparation techniques coupled with GC-MS/MS proves applicable to urinary measurements for PAH exposure studies for general population.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/urina , Hidrocarbonetos Policíclicos Aromáticos/urina , Acetamidas , Fluoracetatos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Técnicas de Diluição do Indicador , Isótopos , Limite de Detecção , Extração Líquido-Líquido/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Espectrometria de Massas em Tandem/métodos
5.
J Expo Sci Environ Epidemiol ; 29(1): 21-32, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29317738

RESUMO

Use of personal care products, such as makeup, soaps, and sunscreen, may expose adolescent girls to potential endocrine disruptors, including phthalates, parabens, and other phenols. We evaluated the relationship between recent self-reported personal care product use and concentrations for urinary metabolites of phthalates, parabens, triclosan, and benzophenone-3 (BP-3) in 100 Latina adolescents. Girls who reported using makeup every day vs. rarely/never had higher urinary concentrations of monoethyl phthalate (MEP) (102.2 ng/mL vs. 52.4 ng/mL, P-value: 0.04), methyl paraben (MP) (120.5 ng/mL vs. 13.4 ng/mL, P-value < 0.01), and propyl paraben (PP) (60.4 ng/mL vs. 2.9 ng/mL, P-value < 0.01). Girls who reported recent use of specific makeup products, including foundation, blush, and mascara, had higher urinary concentrations of MEP, mono-n-butyl phthalate (MBP), MP, and PP. Use of Colgate Total toothpaste was associated with 86.7% higher urinary triclosan concentrations. Use of sunscreen was associated with 57.8% higher urinary concentrations of BP-3. Our findings suggest that personal care product use is associated with higher exposure to certain phthalates, parabens, and other phenols in urine. This may be especially relevant in adolescent girls who have high use of personal care products during a period of important reproductive development.


Assuntos
Cosméticos/efeitos adversos , Disruptores Endócrinos/urina , Hispano-Americanos/estatística & dados numéricos , Parabenos/análise , Fenóis/urina , Ácidos Ftálicos/urina , Adolescente , Compostos Benzidrílicos/urina , Biomarcadores/urina , Disruptores Endócrinos/efeitos adversos , Exposição Ambiental/análise , Feminino , Humanos , Parabenos/efeitos adversos , Autorrelato , Triclosan/urina
6.
PLoS One ; 12(11): e0188498, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29176859

RESUMO

Commuters who spend long hours on roads are exposed to high levels of traffic related air pollutants (TRAPs). Despite some well-known multiple adverse effects of TRAPs on human health, limited studies have focused on mitigation strategies to reduce these effects. In this study, we measured fine particulate matter (PM2.5) and ultrafine particle (UFP) concentrations inside and outside 17 taxis simultaneously while they were driven on roadways. The drivers' urinary monohydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) and malondialdehyde (MDA) concentrations just before and right after the driving tests were also determined. Data were collected under three driving conditions (i.e. no mitigation (NM), window closed (WC), and window closed plus using high efficiency cabin air filters (WC+HECA)) for each taxi and driver. The results show that, compared to NM, the WC+HECA reduced in-cabin PM2.5 and UFP concentrations, by 37% and 47% respectively (p < 0.05), whereas the reductions on PAH exposures were insignificant. Although nonsignificant, a reduction of 17% was also observed in the drivers' urinary MDA under WC+HECA. The MDA concentrations were found to be significantly associated with the in-cabin PM2.5 and UFP concentrations, suggesting the reduction of the drivers' lipid peroxidation can be at least partially attributed to the PM2.5 and UFP reduction by WC+HECA. Overall, these results suggest HECA filters have potential to reduce particle levels inside taxis and protect drivers' health.


Assuntos
Filtros de Ar , Condução de Veículo , Exposição Ambiental , Peroxidação de Lipídeos , Tamanho da Partícula , Humanos
7.
Anal Bioanal Chem ; 409(22): 5307-5317, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28741109

RESUMO

Commonly, analytical methods measuring brominated flame retardants (BFRs) of different chemical polarities in human serum are labor consuming and tedious. Our study used acidified diatomaceous earth as solid-phase extraction (SPE) adsorbent and defatting material to simultaneously determine the most abundant BFRs and their metabolites with different polarities in human serum samples. The analytes include three types of commercial BFRs, tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) isomers, and polybrominated biphenyl ethers (PBDEs), and dominant hydroxylated BDE (OH-PBDE) and methoxylated BDE (MeO-PBDE) metabolites of PBDEs. The sample eluents were sequentially analyzed for PBDEs and MeO-BDEs on online gel permeation chromatography/gas chromatography-electron capture-negative ionization mass spectrometry (online GPC GC-ECNI-MS) and for TBBPA, HBCD, and OH-BDEs on liquid chromatography-tandem mass spectrometry (LC-MS/MS). Method recoveries were 67-134% with a relative standard deviation (RSD) of less than 20%. Method detection limits (MDLs) were 0.30-4.20 pg/mL fresh weight (f.w.) for all analytes, except for BDE-209 of 16 pg/mL f.w. The methodology was also applied in a pilot study, which analyzed ten real samples from healthy donors in China, and the majority of target analytes were detected with a detection rate of more than 80%. To our knowledge, it is the first time for us in effectively determining BFRs of most types in one aliquot of human serum samples. This new analytical method is more specific, sensitive, accurate, and time saving for routine biomonitoring of these BFRs and for integrated assessment of health risk of BFR exposure.


Assuntos
Análise Química do Sangue/métodos , Retardadores de Chama/análise , Éteres Difenil Halogenados/sangue , Compostos de Bromo/análise , Éteres Difenil Halogenados/metabolismo , Humanos , Limite de Detecção , Controle de Qualidade , Extração em Fase Sólida , Fatores de Tempo
8.
Sci Total Environ ; 601-602: 1733-1742, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28628972

RESUMO

BACKGROUND: Many surveys have shown that older children are ubiquitously exposed to bisphenol A (BPA), and many laboratory studies have shown that BPA exposure has adverse effects related to estrogenic disruption, whereas the evidence in infants has not yet been observed. METHODS: Women in early pregnancy were recruited by the Maternal and Child Health and Family Planning Service Center, Daishan, China, from March 2012 to December 2014. After delivery, urine samples were collected from the diapers of 59 infants (0 to 6months of age). Urinary BPA, estradiol (E2), testosterone (T), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and creatinine were analyzed. The partial correlation and multivariable linear regression were applied to assess the associations of BPA with E2, T, FSH, and LH for each of the development stages: at birth, 14days, 28days, 42days, 3months, and 6months. RESULTS: For both genders from birth to 6months, infants showed randomly changed urinary BPA but regularly changed hormones, i.e., the monotonic decreasing E2 and T, the "U" shaping E2/T and upside down "U" shaping FSH and LH with extreme values at approximately the 14-day stage, respectively. However, the creatinine-adjusted FSH for all stages and E2 from 6months were genders different. After adjustment for creatinine, gender, and infant body mass index, BPA was positively associated with E2 both in male (for 14-, 28-, and 42-day stages) and female (for 14-, 28-, 42-day, and 3-month stages) infants; positively associated with E2/T ratio in both male (for 14- and 28-day stages) and female (for 14-day stage) infants; and positively associated with T in female (for 3-month stage) infants. CONCLUSIONS: To the best of our knowledge, this is the first time that associations of BPA with E2, E2/T, and T in infant urine were observed. The results suggested that the infants first demonstrate a surge of steroids after leaving the maternal uterus's steroidogenic environment (i.e., mini-puberty) and may be affected by BPA; this pollution may disrupt the premature gonad function at some important developmental windows.


Assuntos
Compostos Benzidrílicos/urina , Exposição Ambiental/análise , Estradiol/urina , Hormônio Foliculoestimulante/urina , Hormônio Luteinizante/urina , Fenóis/urina , Testosterona/urina , China , Creatinina/urina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez
9.
Environ Int ; 100: 110-120, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28065424

RESUMO

Essentially all women are exposed to polycyclic aromatic hydrocarbons (PAHs), formed during incomplete combustion of organic materials, including fossil fuels, wood, foods, and tobacco. PAHs are ovarian toxicants in rodents, and cigarette smoking is associated with reproductive abnormalities in women. Biomonitoring of hydroxylated PAH (OH-PAH) metabolites in urine provides an integrated measure of exposure to PAHs via multiple routes and has been used to characterize exposure to PAHs in humans. We hypothesized that concentrations of OH-PAHs in urine are associated with reproductive function in women. We recruited women 18-44years old, living in Orange County, California to conduct daily measurement of urinary luteinizing hormone (LH) and estrone 3-glucuronide (E13G) using a microelectronic fertility monitor for multiple menstrual cycles; these data were used to calculate endocrine endpoints. Participants also collected urine samples on cycle day 10 for measurement of nine OH-PAHs. Models were constructed for eight endpoints using a Bayesian mixed modeling approach with subject-specific random effects allowing each participant to act as a baseline for her set of measurements. We observed associations between individual OH-PAH concentrations and follicular phase length, follicular phase LH and E13G concentrations, preovulatory LH surge concentrations, and periovulatory E13G slope and concentration. We have demonstrated the feasibility of using urinary reproductive hormone data obtained via fertility monitors to calculate endocrine endpoints for epidemiological studies of ovarian function during multiple menstrual cycles. The results show that environmental exposure to PAHs is associated with changes in endocrine markers of ovarian function in women in a PAH-specific manner.


Assuntos
Exposição Ambiental , Poluentes Ambientais/urina , Estrona/análogos & derivados , Hormônio Luteinizante/urina , Ciclo Menstrual/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/urina , Adulto , Biomarcadores/urina , California , Estrona/urina , Feminino , Humanos , Adulto Jovem
10.
Environ Sci Technol ; 50(22): 12464-12472, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27700069

RESUMO

Exposures to environmental pollutants in utero may increase the risk of adverse health effects. We measured the concentrations of 59 potentially harmful chemicals in 77 maternal and 65 paired umbilical cord blood samples collected in San Francisco during 2010-2011, including polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs (OH-PBDEs), and perfluorinated compounds (PFCs) in serum and metals in whole blood. Consistent with previous studies, we found evidence that concentrations of mercury (Hg) and lower-brominated PBDEs were often higher in umbilical cord blood or serum than in maternal samples (median cord:maternal ratio > 1), while for most PFCs and lead (Pb), concentrations in cord blood or serum were generally equal to or lower than their maternal pair (median cord:maternal ratio ≤ 1). In contrast to the conclusions of a recent review, we found evidence that several PCBs and OCPs were also often higher in cord than maternal serum (median cord:maternal ratio > 1) when concentrations are assessed on a lipid-adjusted basis. Our findings suggest that for many chemicals, fetuses may experience higher exposures than their mothers and highlight the need to characterize potential health risks and inform policies aimed at reducing sources of exposure.


Assuntos
Poluentes Ambientais , Éteres Difenil Halogenados , Exposição Materna , Monitoramento Ambiental , Feminino , Humanos , Hidrocarbonetos Clorados , Recém-Nascido , Troca Materno-Fetal , Bifenilos Policlorados , Gravidez , São Francisco , População Urbana
11.
Anal Bioanal Chem ; 408(18): 4897-906, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27178547

RESUMO

An improved method based on tandem solid phase extraction (SPE) cleanup and gas chromatography-high resolution mass spectrometry (GC-HRMS) has been validated for a rapid determination of dibenzo-p-dioxins/furans (PCDD/Fs), dioxin-like polychlorinated biphenyls (PCBs), marker polychlorinated biphenyls (M-PCBs), and polybrominated diphenyl ethers (PBDEs) using a large volume (50 mL) of human milk. This method was well validated for the measurement of these analytes in human milk from the general population with low limits of detection (LODs, 0.004-0.12 ng/g lipid), satisfactory accuracy (75-120 % of recoveries), and precision [less than 10 % of relative standard deviations (RSDs)]. To comprehensively evaluate the performance of this method, a good, presently validated and routinely used method based on an automated sample clean-up system (ASCS, based on the commercial acid multilayer silica, basic alumina, and carbon columns) was used in parallel for comparison. Compared with the ASCS method, this method presented comparable specificity. Additionally, this method, in contrast to ASCS method, highly reduced consumption of solvents (40 mL versus 500 mL), which results in much lower background in the procedural blank, reduced time, and enhanced sample pretreatment throughput. This method was also applied in a pilot study to measure a batch of human milk samples with satisfactory results. Graphical Abstract Characteristics of the application of tandem SPE cleanup for determination of PCDD/Fs, DL-PCBs,M-PCBs and PBDEs in human milk.


Assuntos
Poluentes Ambientais/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Hidrocarbonetos Aromáticos/análise , Leite/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Humanos , Hidrocarbonetos Aromáticos/química , Bifenilos Policlorados , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes/métodos
12.
J Chromatogr A ; 1445: 80-92, 2016 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-27063369

RESUMO

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.


Assuntos
Cromatografia Líquida , Pirrolidinonas/química , Pirrolidinonas/urina , Espectrometria de Massas em Tandem , Urinálise/métodos , Animais , Biotransformação , Masculino , Pirrolidinonas/metabolismo , Ratos
13.
Environ Health Perspect ; 124(9): 1406-13, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27081854

RESUMO

BACKGROUND: Although the chlorinated flame retardant Dechlorane (Dec) 602 has been detected in food, human blood, and breast milk, there is limited information on potential health effects, including possible immunotoxicity. OBJECTIVES: We determined the immunotoxic potential of Dec 602 in mice by examining the expression of phenotypic markers on thymocyte and splenic lymphocyte subsets, Th1/Th2 transcription factors, and the production of cytokines and antibodies. METHODS: Adult male C57BL/6 mice were orally exposed to environmentally relevant doses of Dec 602 (1 and 10 µg/kg body weight per day) for 7 consecutive days. Thymocyte and splenic CD4 and CD8 subsets and splenocyte apoptosis were examined by flow cytometric analysis. Cytokine expression was measured at both the mRNA and the protein levels. Levels of the transcription factors Th1 (T-bet and STAT1) and Th2 (GATA3) were determined using quantitative real-time polymerase chain reaction (qPCR). Serum levels of immunoglobulins IgG1, IgG2a, IgG2b and IgE were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Splenic CD4+ and CD8+ T cell subsets were decreased compared with vehicle controls, and apoptosis was significantly increased in splenic CD4+ T cells. Expression (mRNA and protein) of Th2 cytokines [interleukin (IL)-4, IL-10, and IL-13] increased, and that of Th1 cytokines [IL-2, interferon (IFN)-γ and tumor necrosis factor (TNF)-α] decreased. The Th2 transcriptional factor GATA3 increased, whereas the Th1 transcriptional factors T-bet and STAT1 decreased. As additional indicators of the Th2-Th1 imbalance, production of IgG1 was significantly increased, whereas IgG2a was reduced. CONCLUSIONS: To our knowledge, we are the first to report evidence of the effects of Dec 602 on immune function in mice, with findings indicating that Dec 602 exposure favored Th2 responses and reduced Th1 function. CITATION: Feng Y, Tian J, Xie HQ, She J, Xu SL, Xu T, Tian W, Fu H, Li S, Tao W, Wang L, Chen Y, Zhang S, Zhang W, Guo TL, Zhao B. 2016. Effects of acute low-dose exposure to the chlorinated flame retardant dechlorane 602 and Th1 and Th2 immune responses in adult male mice. Environ Health Perspect 124:1406-1413; http://dx.doi.org/10.1289/ehp.1510314.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Poluentes Ambientais/toxicidade , Retardadores de Chama/toxicidade , Hidrocarbonetos Clorados/toxicidade , Sistema Imunitário/efeitos dos fármacos , Compostos Policíclicos/toxicidade , Linfócitos T/efeitos dos fármacos , Equilíbrio Th1-Th2/efeitos dos fármacos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia
14.
Environ Health Perspect ; 124(10): 1600-1607, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26947464

RESUMO

BACKGROUND: Personal care products are a source of exposure to potentially endocrine-disrupting chemicals such as phthalates, parabens, triclosan, and benzophenone-3 (BP-3) for adolescent girls. METHODS: We enrolled 100 Latina girls in a youth-led, community-based participatory research intervention study to determine whether using personal care products whose labels stated they did not contain these chemicals for 3 days could lower urinary concentrations. Pre- and postintervention urine samples were analyzed for phthalate metabolites, parabens, triclosan, and BP-3 using high-performance liquid chromatography/tandem mass spectrometry. RESULTS: Urinary concentrations of mono-ethyl phthalate (MEP) decreased by 27.4% (95% CI: -39.3, -13.2) on average over the 3-day intervention; no significant changes were seen in urinary concentrations of mono-n-butyl phthalate (MnBP) and mono-isobutyl phthalate (MiBP). Methyl and propyl paraben concentrations decreased by 43.9% (95% CI: -61.3, -18.8) and 45.4% (95% CI: -63.7, -17.9), respectively. Unexpectedly, concentrations of ethyl and butyl paraben concentrations increased, although concentrations were low overall and not detected in almost half the samples. Triclosan concentrations decreased by 35.7% (95% CI: -53.3, -11.6), and BP-3 concentrations decreased by 36.0% (95% CI: -51.0, -16.4). DISCUSSION: This study demonstrates that techniques available to consumers, such as choosing personal care products that are labeled to be free of phthalates, parabens, triclosan, and BP-3, can reduce personal exposure to possible endocrine-disrupting chemicals. Involving youth in the design and implementation of the study was key to recruitment, retention, compliance, and acceptability of the intervention. CITATION: Harley KG, Kogut K, Madrigal DS, Cardenas M, Vera IA, Meza-Alfaro G, She J, Gavin Q, Zahedi R, Bradman A, Eskenazi B, Parra KL. 2016. Reducing phthalate, paraben, and phenol exposure from personal care products in adolescent girls: findings from the HERMOSA Intervention Study. Environ Health Perspect 124:1600-1607; http://dx.doi.org/10.1289/ehp.1510514.

15.
Environ Int ; 88: 281-287, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26821331

RESUMO

Firefighters are at increased risk for exposure to toxic chemicals compared to the general population, but few studies of this occupational group have included biomonitoring. We measured selected phenolic chemicals in urine collected from 101 Southern California firefighters. The analytes included bisphenol A (BPA), triclosan, benzophenone-3 (BP-3), and parabens, which are common ingredients in a range of consumer products. BP-3, BPA, triclosan, and methyl paraben were detected in almost all study subjects (94-100%). The BP-3 geometric mean for firefighters was approximately five times higher than for a comparable National Health and Nutrition Examination Survey (NHANES) subgroup. Demographic and exposure data were collected from medical records and via a questionnaire, and covariates were examined to assess associations with BP-3 levels. BP-3 levels were elevated across all firefighter age groups, with the highest levels observed in the 35 to 39year old group. Body fat percentage had a significant inverse association with BP-3 concentrations. Our results indicate pervasive exposure to BP-3, BPA, triclosan, and methyl paraben in this population of firefighters, consistent with studies of other populations. Further research is needed to investigate possible explanations for the higher observed BP-3 levels, such as occupational or California-specific exposures.


Assuntos
Benzofenonas/urina , Exposição Ambiental , Poluentes Ambientais/urina , Fenóis/urina , Adulto , California , Monitoramento Ambiental , Feminino , Bombeiros , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais
16.
Chemosphere ; 137: 14-24, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25966445

RESUMO

Human milk samples were collected from 150 mothers in 2011 and 2012 in Shanghai, China and analyzed for 17 polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (DL-PCBs). The up-bound Toxic Equivalent Quantity (TEQ) ranged from 0.27 to 16.8 pg TEQ/g lipid (mean 5.4 pg TEQ/g lipid) for ∑PCDD/Fs and from 0.75 to 10.2 pg TEQ/g lipid (mean 2.9 pg TEQ/g lipid) for ∑DL-PCBs. TEQs in our study were lower than those in most countries worldwide, and displayed a notable uptrend, in contrast with those in China's national survey in 2007. TEQs in mother milks from urban areas were higher than those from rural areas, and an orderly distribution was found in four geographical regions: Eastern China>Central China≈Southwestern China>Northwestern China. Levels of analytes in Shanghai native mothers' milk ranked the first among those from all provinces and cities investigated. Migrant mothers to Shanghai from other inland provinces could potentially represent the population for exposure and risk assessment in their birth and grown-up places. Both the distribution and the uptrend were associated with release of these pollutants due to rapid industrialization and urbanization in China. Fine correlations were observed between TEQs and age of mothers, and weak correlations between TEQs and consumption of meat & meat products. Participants, who preferred both fresh water and marine fish to freshwater fish only, were prone to be exposed to higher level of PCBs. The estimated daily intake (EDI) doses for breastfed neonates entirely exceeded the tolerable intake dose by WHO.


Assuntos
Benzofuranos/análise , Monitoramento Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Leite Humano/química , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Polímeros/análise , Adolescente , Adulto , Animais , Aleitamento Materno , China , Feminino , Peixes , Humanos , Recém-Nascido , Masculino , Mães , Dibenzodioxinas Policloradas/análise , Medição de Risco , Fatores de Tempo , Adulto Jovem
17.
Sci Total Environ ; 524-525: 74-80, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25889546

RESUMO

Polycyclic aromatic hydrocarbons (PAHs), benzene and toluene (BT) are ubiquitous toxic pollutants in the environment. Children are sensitive and susceptible to exposure to these contaminants. To investigate the potential oxidative DNA damage from the co-exposure of PAHs and BT in children, 87 children (aged 3-6) from a kindergarten in Guangzhou, China, were recruited. Ten urinary PAHs and four BT metabolites, as well as 8-hydroxy-2'-deoxyguanosine (8-OHdG, a biomarker of oxidative DNA damage)in urine, were determined using a liquid chromatography tandem mass spectrometer. The results demonstrated that the levels of PAHs and BT in children from Guangzhou were 2-30 times higher than those in children from the other countries based on a comparison with recent data from the literature. In particular, the difference is more substantial for pyrene and volatile BT. Co-exposure to PAHs and BT could lead to additive oxidative DNA damage. Significant dose-effects were observed between the sum concentration of urinary monohydroxylated metabolites of PAHs (∑OH-PAHs), the sum concentration of the metabolites of BT (∑BT) and 8-OHdG levels. Every one percent increase in urinary PAHs and BT generated 0.33% and 0.02% increases in urinary 8-OHdG, respectively. We also determined that the urinary levels of PAHs and BT were negatively associated with the age of the children. Moreover, significant differences in the levels of ∑OH-PAHs and ∑BT were determined between 3- and 6-year-old children (p<0.05), which may be caused by different metabolism capabilities or inhalation frequencies. In conclusion, exposure to PAHs or BT could lead to oxidative DNA damage, and 8-OHdG is a good biomarker for indicating the presence of DNA damage. There exists a significant dose-effect relationship between PAH exposure, BT exposure and the concentration of 8-OHdG in urine. Toddlers (3-4 years old) face a higher burden of PAH and BT exposure compared with older children.


Assuntos
Poluentes Atmosféricos/análise , Benzeno/análise , Exposição Ambiental/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Tolueno/análise , 8-Hidroxi-2'-Desoxiguanosina , Poluentes Atmosféricos/toxicidade , Benzeno/toxicidade , Biomarcadores/metabolismo , Criança , Pré-Escolar , China , Dano ao DNA , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Relação Dose-Resposta a Droga , Exposição Ambiental/estatística & dados numéricos , Humanos , Estresse Oxidativo/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Tolueno/toxicidade
18.
Anal Bioanal Chem ; 407(14): 4131-41, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25903021

RESUMO

This study developed a new method for the analysis of 20 phenolic compounds in human urine. The urine samples were prepared by hydrochloric acid (HCl) hydrolysis, liquid-liquid extraction (LLE), and solid-phase extraction (SPE) cleanup. We found that HCl hydrolysis is of similar effectiveness to, and much cheaper than, the traditional enzymatic method. Vanillic acid was co-eluted with butyl paraben and interfered with the determination of butyl paraben in urine. K2CO3-treated-silica-gel SPE was designed to efficiently eliminate interference from the endogenous organic acids (especially vanillic acid) in urine. After derivatization, the samples were analyzed by large-volume-injection gas chromatography-tandem mass spectrometry (LVI-GC-MS-MS). Good linearity (R (2) ≥ 0.996) was established in the range 0.1-100 ng mL(-1) for all analytes. Method detection limits (MDLs) were 0.7-9.8 pg mL(-1). Intraday (n = 5) and interday (n = 5 days) validation was performed, with satisfactory accuracy (recovery: 70-126 % and 73-107 %, respectively) and precision (RSD ≤ 19 %) at two levels (low: 0.1 and 0.5 ng mL(-1); high: 5 and 10 ng mL(-1)). The method was used in a population study and achieved more than 85 % detection for most analytes; mean analyte concentrations were in the range 0.01-185 ng mL(-1). The method is suitable for the analysis of multiple phenolic metabolites in human urine.


Assuntos
Carbonatos/química , Cromatografia Gasosa/métodos , Ácido Clorídrico/química , Fenóis/urina , Potássio/química , Dióxido de Silício/química , Extração em Fase Sólida/métodos , Adulto , Pré-Escolar , Humanos , Hidrólise , Lactente , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
19.
J AOAC Int ; 98(2): 517-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25905759

RESUMO

In order to better distinguish the different toxic inorganic and organic forms of arsenic (As) exposure in individuals, we have developed and validated a simple and robust analytical method for determining the following six As species in human urine: arsenous (III) acid (As-III), As (V) acid, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine (AsB), and arsenocholine. In this method, human urine is diluted using a pH 5.8 buffer, separation is performed using an anion exchange column with isocratic HPLC, and detection is achieved using inductively coupled plasma-MS. The method uses a single mobile phase consisting of low concentrations of both phosphate buffer (5 mM) and ammonium nitrate salt (5 mM) at pH 9.0; this minimizes the column equilibration time and overcomes challenges with separation between AsB and As-III. In addition, As-III oxidation is prevented by degassing the sample preparation buffer at pH 5.8, degassing the mobile phase online at pH 9.0, and by the use of low temperature (-70 °C) and flip-cap airtight tubes for long term storage of samples. The method was validated using externally provided reference samples. Results were in agreement with target values at varying concentrations and successfully passed external performance test criteria. Internal QC samples were prepared and repeatedly analyzed to assess the method's long-term precision, and further analyses were completed on anonymous donor urine to assess the quality of the method's baseline separation. Results from analyses of external reference samples agreed with target values at varying concentrations, and results from precision studies yielded absolute CV values of 3-14% and recovery from 82 to 115% for the six As species. Analysis of anonymous donor urine confirmed the well-resolved baseline separation capabilities of the method for real participant samples.


Assuntos
Arsênico/química , Arsênico/urina , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
J Occup Environ Med ; 57(1): 88-97, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25563545

RESUMO

OBJECTIVE: To assess California firefighters' blood concentrations of selected chemicals and compare with a representative US population. METHODS: We report laboratory methods and analytic results for cadmium, lead, mercury, and manganese in whole blood and 12 serum perfluorinated chemicals in a sample of 101 Southern California firefighters. RESULTS: Firefighters' blood metal concentrations were all similar to or lower than the National Health and Nutrition Examination Survey (NHANES) values, except for six participants whose mercury concentrations (range: 9.79 to 13.42 µg/L) were close to or higher than the NHANES reporting threshold of 10 µg/L. Perfluorodecanoic acid concentrations were elevated compared with NHANES and other firefighter studies. CONCLUSIONS: Perfluorodecanoic acid concentrations were three times higher in this firefighter group than in NHANES adult males. Firefighters may have unidentified sources of occupational exposure to perfluorinated chemicals.


Assuntos
Monitoramento Ambiental/métodos , Bombeiros , Fogo , Exposição Ocupacional/análise , Adulto , Fatores Etários , Ácidos Alcanossulfônicos/sangue , Cádmio/sangue , California , Ácidos Decanoicos/sangue , Feminino , Fluorcarbonetos/sangue , Ácidos Heptanoicos/sangue , Humanos , Hidrocarbonetos Fluorados/sangue , Chumbo/sangue , Masculino , Manganês/sangue , Mercúrio/sangue , Pessoa de Meia-Idade , Inquéritos Nutricionais , Exposição Ocupacional/normas , Sulfonamidas/sangue , Adulto Jovem
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