RESUMO
Objective: To investigate the correlation between the prenatal exposure of per-/polyfluoroalkyl substances (PFASs) and the neonatal outcome. Methods: A total of 506 maternal infant cohort samples were collected in Hangzhou, Zhejiang province from 2020 to 2021. The exposure levels of seven PFASs in maternal serum before delivery were detected by solid-phase extraction-ultra performance liquid chromatography tandem mass spectrometry. Multivariable linear regression model was used to analyze the influence of prenatal exposure of PFASs on birth weight, birth length and Apgar score. Results: The maternal age, prenatal body mass index and gestation age were (31.3±4.3) years old, (26.7±3.2) kg/m2 and (265.0±28.3) days, respectively. The birth weight, birth length and scores of Apgar-1 and Apgar-5 were (3.1±0.8) kg, (49.3±2.9) cm, (9.88±0.47) points and (9.99±0.13) points, respectively. PFASs were widely distributed in maternal serum, with the highest concentration of (18.453±19.557) ng/ml, (6.756±9.379) ng/ml and (5.057±8.555) ng/ml for perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS) and 6â¶2 chlorinated polyfluorinated ether sulfonate (Cl-PFESA), respectively. Maternal age, parity and delivery mode were associated with the exposure level of PFASs (P<0.05). Subgroup analysis showed that PFOS had negative effects on birth weight (ß=-0.958), birth length (ß=-0.073) and Apgar-5 score (ß=-0.288) for neonates in the low birth weight (LBW) group. 6â¶2 Cl-PFESA and 8â¶2 Cl-PFESA inhibited the birth weight (ß=-0.926; ß=-0.552) and length (ß=-0.074; ß=-0.045) of newborn in the LBW group. In addition, 4â¶2 fluorotelomer sulfonate (FTS) was associated with increased birth weight (ß=0.111) and decreased Apgar-5 score (ß=-0.030) in the normal weight group. Conclusion: Prenatal exposure to PFASs is associated with birth weight, birth length and Apgar-5 score. It is necessary to continue to pay attention to the impact of PFASs on fetal growth and development through maternal-fetal transmission.
Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Recém-Nascido , Feminino , Humanos , Adulto , Peso ao Nascer , Ácidos Alcanossulfônicos/análise , Alcanossulfonatos/análise , Fluorocarbonos/análise , Éteres/análise , Etil-Éteres/análise , Poluentes Ambientais/análise , Exposição MaternaRESUMO
Polybrominated diphenyl ethers (PBDEs) as a typical brominated flame retardant (BFR) have attracted worldwide attention due to the high environmental risk and resistance to conventional remediation processes. In this study, thermally activated persulfate (TAP) process was applied to degrade 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), which is the most toxic and representative PBDEs in e-waste dismantling sites. Impact factors such as PDS dosage, heating temperature, and initial pH were evaluated. Results showed that BDE-47 can be 100% degraded within 180 min under the condition of PDS:BDE-47 = 1000:1, 60 °C, and pH = 7. Quenching experiments combined with EPR analysis further proved the important role of SO4·- in oxidating BDE-47. According to high-resolution mass spectrometry (HRMS) analysis, only one oxidation product of low toxicity was detected during the oxidation process. Theoretical calculations further revealed that the oxidation process mainly involved radical attack at C-Br bond, cleavage of C-Br bond, and fission of ether bond, and HSO4· may also play an important role in BDE-47 degradation in TAP system. In addition, TAP system exhibited universality as all selected PBDE congeners can be degraded, and the degradation rate of PBDEs was greatly affected by the number of substituted Br atoms in a negative trend. Overall, these findings indicate that TAP can be applied as an effective method for removal of PBDEs, and we provide a new insight for the practical application of TAP technology in BDE-47 degradation from experimental and theoretical aspects.
Assuntos
Retardadores de Chama , Éteres Difenil Halogenados , Éteres Difenil Halogenados/análise , Éter , Etil-Éteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Retardadores de Chama/análiseRESUMO
Recent studies have suggested that there are significant amounts of various alkyl ether (Alk-O-Alk; Alk = alkyl) moieties in a spruce native lignin preparation, milled wood lignin (SMWL). However, the comprehensive NMR assignment to these moieties has not been addressed yet. This study focused on investigating different types of Alk-O-Alk structures at the α- and γ-positions of the lignin side chain in an heteronuclear single-quantum coherence (HSQC) spectrum of SMWL using experimental NMR data of lignin and synthesized model compounds. Ambiguous structural features were predicted by computer simulation of 1H and 13C NMR spectra to complement the experimental NMR data. As a result, specific regions in the HSQC spectrum were attributed to different Alk-O-Alk moieties of Alk-O-Alk/ß-O-4 and Alk-O-Alk/ß-ß' structures. However, the differences between the specific regions were rather subtle; they were not well separated from each other and some major lignin moieties. Furthermore, SMWL contained a large variety of Alk-O-Alk moieties but in minute individual amounts, resulting in rather broad, superimposing resonances. Thus, evaluation did not allow assigning individual types of Alk-O-Alk moieties from the HSQC spectra; instead, they were quantified as total (α- and γ-linked) Alk-O-Alk based on the balance of structural units in the 13C NMR spectra. At last, potential formation mechanisms of various Alk-O-Alk ether structures in lignin biosynthesis, lignin aging, and during ball milling of wood were hypothesized and discussed.
Assuntos
Éter , Lignina , Lignina/química , Madeira/química , Simulação por Computador , Estrutura Molecular , Éteres , Etil-Éteres/análise , Receptores Proteína Tirosina QuinasesRESUMO
Objective: To investigate the correlation between the prenatal exposure of per-/polyfluoroalkyl substances (PFASs) and the neonatal outcome. Methods: A total of 506 maternal infant cohort samples were collected in Hangzhou, Zhejiang province from 2020 to 2021. The exposure levels of seven PFASs in maternal serum before delivery were detected by solid-phase extraction-ultra performance liquid chromatography tandem mass spectrometry. Multivariable linear regression model was used to analyze the influence of prenatal exposure of PFASs on birth weight, birth length and Apgar score. Results: The maternal age, prenatal body mass index and gestation age were (31.3±4.3) years old, (26.7±3.2) kg/m2 and (265.0±28.3) days, respectively. The birth weight, birth length and scores of Apgar-1 and Apgar-5 were (3.1±0.8) kg, (49.3±2.9) cm, (9.88±0.47) points and (9.99±0.13) points, respectively. PFASs were widely distributed in maternal serum, with the highest concentration of (18.453±19.557) ng/ml, (6.756±9.379) ng/ml and (5.057±8.555) ng/ml for perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS) and 6∶2 chlorinated polyfluorinated ether sulfonate (Cl-PFESA), respectively. Maternal age, parity and delivery mode were associated with the exposure level of PFASs (P<0.05). Subgroup analysis showed that PFOS had negative effects on birth weight (β=-0.958), birth length (β=-0.073) and Apgar-5 score (β=-0.288) for neonates in the low birth weight (LBW) group. 6∶2 Cl-PFESA and 8∶2 Cl-PFESA inhibited the birth weight (β=-0.926; β=-0.552) and length (β=-0.074; β=-0.045) of newborn in the LBW group. In addition, 4∶2 fluorotelomer sulfonate (FTS) was associated with increased birth weight (β=0.111) and decreased Apgar-5 score (β=-0.030) in the normal weight group. Conclusion: Prenatal exposure to PFASs is associated with birth weight, birth length and Apgar-5 score. It is necessary to continue to pay attention to the impact of PFASs on fetal growth and development through maternal-fetal transmission.
Assuntos
Gravidez , Recém-Nascido , Feminino , Humanos , Adulto , Peso ao Nascer , Efeitos Tardios da Exposição Pré-Natal , Ácidos Alcanossulfônicos/análise , Alcanossulfonatos/análise , Fluorocarbonos/análise , Éteres/análise , Etil-Éteres/análise , Poluentes Ambientais/análise , Exposição MaternaRESUMO
The OH-initiated oxidation reactions of chloromethyl ethyl ether (CH2ClOCH2CH3) have been presented by using quantum calculation methods. The Minnesota functional (M06-2X) of the density functional theory method along with a polarization and diffuse 6-311++G(d,p) basis set is chosen for optimization and frequency calculations for H-abstractions from CH2ClOCH2CH3 molecules by OH radicals. Furthermore, the CCSD(T) method along with the same basis set is used for energy refinement of all optimized structures to obtain more accurate energies of the species. Our thermo-chemical calculation results show that the CËHClOCH2CH3 product radical is more stable, corresponding to hydrogen atom abstraction from the -CH2Cl site, than others while the energy profile results indicate that the H-atom abstracted from the -OCH2 site follows the minimum energy path compared to other channels. The rate constants are computed using canonical transition state theory (CTST) within the temperature range of 250-450 K at 1 atm. The overall rate constant (at 298 K) for the abstraction reactions is found to be consistent with the earlier reported rate constant. The percentage branching ratios of different abstraction channels and the lifetime of chloromethyl ethyl ether are also given herein. We further investigated the unimolecular decomposition pathways of the CH2ClOCH(OË)CH3 radical and found that unimolecular C-C bond scission is the kinetically and thermodynamically more feasible pathway compared to other unimolecular decomposition reactions.
Assuntos
Poluentes Atmosféricos/análise , Química Computacional , Etil-Éteres/análise , Radical Hidroxila/química , Poluentes Atmosféricos/química , Etil-Éteres/química , Cinética , Modelos Químicos , Modelos Moleculares , Oxirredução , TermodinâmicaRESUMO
BACKGROUND: Biomarkers of alcohol consumption are important not only in forensic contexts, e.g., in child custody proceedings or as documentation of alcohol abstinence after temporary confiscation of a driver's license. They are increasingly being used in clinical medicine as well for verification of abstinence or to rule out the harmful use of alcohol. METHODS: This review is based on pertinent publications that were retrieved by a selective literature search in PubMed concerning the direct and indirect alcohol markers discussed here, as well as on the authors' experience in laboratory analysis and clinical medicine. RESULTS: Alongside the direct demonstration of ethanol, the available markers of alcohol consumption include the classic indirect markers carbohydrate-deficient transferrin (CDT), gamma-glutamyltransferase (GGT), and mean corpuscular volume (MCV) as well as direct alcohol markers such as ethyl glucuronide (EtG) and ethyl sulfate (EtS) in serum and urine and EtG and fatty acid ethyl esters (FAEE) in hair. Phosphatidylethanol (PEth) is a promising parameter that com - plements the existing spectrum of tests with high specificity (48-89%) and sensi - tivity (88-100%). In routine clinical practice, the demonstration of positive alcohol markers often leads patients to admit previously denied alcohol use. This makes it possible to motivate the patient to undergo treatment for alcoholism. CONCLUSION: The available alcohol biomarkers vary in sensitivity and specificity with respect to the time period over which they indicate alcohol use and the minimum extent of alcohol use that they can detect. The appropriate marker or combination of markers should be chosen in each case according to the particular question that is to be answered by laboratory analysis.
Assuntos
Consumo de Bebidas Alcoólicas/sangue , Pesos e Medidas/normas , Consumo de Bebidas Alcoólicas/metabolismo , Consumo de Bebidas Alcoólicas/urina , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/urina , Etil-Éteres/análise , Etil-Éteres/metabolismo , Ciências Forenses/métodos , Ciências Forenses/normas , Glucuronatos/análise , Glucuronatos/sangue , Glicerofosfolipídeos/análise , Glicerofosfolipídeos/sangue , Cabelo/enzimologia , Cabelo/metabolismo , Cabelo/patologia , Humanos , Jurisprudência , Pessoa de Meia-Idade , Ésteres do Ácido Sulfúrico/análise , Ésteres do Ácido Sulfúrico/sangue , Ésteres do Ácido Sulfúrico/urina , Fatores de Tempo , Transferrina/análogos & derivados , Transferrina/análise , gama-Glutamiltransferase/análise , gama-Glutamiltransferase/sangueRESUMO
Fatty acid ethyl esters (FAEE) are direct metabolites of ethanol and have been shown to be suitable markers for the evaluation of alcohol consumption. Previous research has suggested that the regular use of alcohol containing cosmetic products can influence the concentration of FAEE detected in hair. In this study we investigated the influence of alcohol containing and alcohol free hair cosmetics (hairspray and waxes) on the FAEE concentrations in hair. The effect of cosmetic treatment was measured against the impact on ethyl palmitate in isolation as compared to the sum of four esters. 10 volunteers treated part of their scalp with cosmetic products every day during a 2 month period (alcohol free hairspray n=2, hairspray containing alcohol (42% by volume) n=3, alcohol free wax n=2, wax containing alcohol (11% by volume) n=3). After the 2 month period of cosmetic application hair samples from volunteers were collected from both sides of the scalp. Hair samples were washed with n-heptane, and then cut finely into small pieces. All samples were subjected to clean-up by HS-SPME and then GC PCI-MS/MS for analysis of FAEEs. Comparison of FAEE concentrations between treated and untreated hair showed in some instances that application of hair spray or wax products caused an increase in FAEE levels. Products containing alcohol caused a more substantial increase in alcohol metabolite concentrations in hair when compared to alcohol free products. Three volunteers using an alcohol based hairspray in the study experienced a significant increase in FAEE levels (+27.4%, +205.5%, and +1287.5%), with one of the volunteers showing levels below the cut off for 'abstinence' in the untreated scalp portion, and levels above the cut off for 'chronic excessive consumption' in the treated scalp portion. Performance evaluation of ethyl palmitate as sole marker, compared to the sum of four esters approach suggested that the two quantification approaches react in a very similar manner to the application of hair sprays and waxes. We would suggest that the interpretative value of FAEE hair measurements from people reporting the use of alcohol based hairsprays are treated with caution.
Assuntos
Etanol/análise , Etil-Éteres/análise , Ácidos Graxos/análise , Preparações para Cabelo/química , Cabelo/química , Solventes/análise , Adolescente , Adulto , Biomarcadores/análise , Criança , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Ácidos Palmíticos/análise , Microextração em Fase Sólida , Adulto JovemRESUMO
There are several studies on bioaccumulation and biomagnification of nonylphenol (NP) and its ethoxylates (NPEOs), but their toxico-kinetic mechanisms remain unclear. In the present investigation, we explored the accumulation of NP and NPEOs in estuarine-marine food chains with a bioaccumulation model comprising five trophic levels. Using this model, we estimated uptake and elimination rate constants for NPEOs based on the organisms' weight and lipid content and the chemicals' Kow. Further, we calculated accumulation factors for NP and NPEOs, including biota-sediment accumulation factors (BSAF) and biomagnification factors (BMF), and compared these to independent field measurements collected in the Western Scheldt estuary in The Netherlands and field data reported in the literature. The estimated BSAF values for NP and total NPEOs were below 1 for all trophic levels. The estimated BMF values were around 1 for all trophic levels except for the highest level (carnivorous mammals and birds). For this trophic level, the estimated BMF value varied between 0.1 and 2.4, depending on the biotransformation capacity. For all trophic levels, except primary producers, the accumulation estimates that accounted for biotransformation of NPEOs into NP were closer to the field data than model estimates that did not include biotransformation, indicating that NP formation by biotransformation of NPEOs might occur in organisms.
Assuntos
Organismos Aquáticos/metabolismo , Etil-Éteres/análise , Fenóis/análise , Poluentes Químicos da Água/análise , Animais , Biotransformação , Aves/metabolismo , Etil-Éteres/química , Etil-Éteres/farmacocinética , Cadeia Alimentar , Modelos Teóricos , Países Baixos , Fenóis/química , Fenóis/farmacocinética , Poluentes Químicos da Água/química , Poluentes Químicos da Água/farmacocinéticaRESUMO
Ethyl tert-butyl ether (ETBE) is an upcoming groundwater pollutant in Europe whose environmental fate has been less investigated, thus far. In the present study, we investigated the in situ biodegradation of ETBE in a fuel-contaminated aquifer using compound-specific stable isotope analysis (CSIA), and in situ microcosms in combination with total lipid fatty acid (TLFA)-stable isotope probing (SIP). In a first field investigation, CSIA revealed insignificant carbon isotope fractionation, but low hydrogen isotope fractionation of up to +14 along the prevailing anoxic ETBE plume suggesting biodegradation of ETBE. Ten months later, oxygen injection was conducted to enhance the biodegradation of petroleum hydrocarbons (PH) at the field site. Within the framework of this remediation measure, in situ microcosms loaded with [(13)C6]-ETBE (BACTRAP(®)s) were exposed for 119 days in selected groundwater wells to assess the biodegradation of ETBE by TLFA-SIP under the following conditions: (i) ETBE as main contaminant; (ii) ETBE as main contaminant subjected to oxygen injection; (iii) ETBE plus other PH; (iv) ETBE plus other PH subjected to oxygen injection. Under all conditions investigated, significant (13)C-incorporation into microbial total lipid fatty acids extracted from the in situ microcosms was found, providing clear evidence of ETBE biodegradation.
Assuntos
Isótopos de Carbono/análise , Monitoramento Ambiental/métodos , Etil-Éteres/análise , Água Subterrânea , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Fracionamento Químico , Ácidos Graxos/química , Hidrogênio/análise , Hidrogênio/química , Concentração de Íons de Hidrogênio , Éteres Metílicos/análise , Compostos Orgânicos/química , Oxigênio/química , TemperaturaRESUMO
Four different pellicular stationary phases (i.e. octadecylsilane, octasilane, Phenyl-Hexyl and pentafluorophenyl) were investigated for the chromatographic resolution of alkylphenols (APs), alkylphenols polyethoxylates (APnEOs) and alkylphenoxy carboxylates (APECs) using mixtures of water and organic solvents (i.e. methanol, acetonitrile and tetrahydrofuran) as eluents, in order to obtain their determination by a single LC-MS/MS run. In fact, alkylphenols and alkylphenoxy carboxylates must be analysed in negative ion mode, whereas alkylphenols polyethoxylates undergo ionisation only in positive ion mode, and therefore, two distinct LC-MS/MS analysis are commonly adopted. The best resolution among the aforementioned target analytes was achieved on the pentafluorophenyl column, eluting with an acidified water-acetonitrile-tetrahydrofuran mixture and using the post column addition of an ammonia solution in methanol for the detection of positively ionisable compounds. Under these optimized chromatographic conditions the investigated compounds were determined via a single chromatographic run, with only one polarity switch, in 15min, achieving the following instrumental detection limits: 600pg for AP1EOs, 0.8-14pg for AP2EOs, 10.4-150pg for APs and 4.4-4.8pg for APECs. The chromatographic method was coupled with solid-phase extraction and clean-up procedures and successfully applied to the analysis of wastewater and surface water samples, highlighting mean concentration ranging from 6ng/L for 4-t-OP1EC to 1434ng/L for 4-NP1121EC, depending on the sample analysed.
Assuntos
Ácidos Carboxílicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Etil-Éteres/análise , Fenóis/análise , Espectrometria de Massas em Tandem/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Água/química , Limite de Detecção , Extração em Fase Sólida/métodosAssuntos
Alcoolismo/diagnóstico , Etil-Éteres/análise , Ácidos Graxos/análise , Glucuronatos/análise , Cabelo/química , Biomarcadores/análise , Depressores do Sistema Nervoso Central/farmacocinética , Cromatografia Gasosa , Etanol/farmacocinética , Humanos , Sociedades Científicas , Microextração em Fase Sólida , Espectrometria de Massas em TandemRESUMO
This article presents results from 1872 hair samples, which were analyzed for fatty acid ethyl esters (FAEEs) and ethyl glucuronide (EtG). The results were evaluated in the context of self-reported drinking behavior, the use of hair cosmetics, the gender of the sample donors and hair sample length. For comparison, CDT and GGT in serum were available in 477 and 454 cases, respectively. A number of alcohol abstainers or low moderate drinkers and excessive drinkers were selected for assessment of cut-offs for FAEEs in the proximal 6cm hair segments and for EtG in the proximal 3cm hair segments. Cut-off values were assessed by ROC analysis. It was found that the cut-offs of 1.0ng/mg FAEE and 30pg/mg EtG presently used for excessive drinking lead to a low portion of false positives (4% and 3% respectively) but to a higher portion of false negatives (23% and 25% respectively). Comparison of the mean and medium concentrations in samples without any reported hair cosmetics (N=1079) and in samples with reported use of hair spray (N=79) showed an increase by the factor of about two for FAEE but no significant difference for EtG. Mean values of EtG were decreased by 80% in bleached samples (N=164) and by 63% in dyed samples (N=96). There was no significant effect of bleaching and dyeing on FAEE. Hair gel and hair wax, oil or grease showed no significant effect on both FAEE and EtG. With respect to gender and investigated hair length ambiguous results were obtained because of major differences in the compared subpopulations of male with higher alcohol consumption and mainly shorter hair, and less drinking female with longer hair. For excessive drinkers FAEEs in the 0-6cm hair segment and EtG in the 0-3cm segment decreased with increasing time of reported abstinence before sample collection. These drinkers attain the level of teetotalers only after more than 10 months of abstinence. In comparison to scalp hair, FAEEs recovered from armpit hair and leg hair were lower and from chest hair were higher. EtG in armpit hair was lower and in leg hair higher than in scalp hair. It is concluded that the combined use of FAEE and EtG essentially increases the accuracy of interpretation since both markers complement each other by a different sensitivity to sources of error.
Assuntos
Alcoolismo/diagnóstico , Etil-Éteres/análise , Ácidos Graxos/análise , Glucuronatos/análise , Cabelo/química , Consumo de Bebidas Alcoólicas , Biomarcadores/análise , Cromatografia Líquida , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Preparações para Cabelo/efeitos adversos , Humanos , Masculino , Curva ROC , Autorrelato , Sensibilidade e Especificidade , Fatores Sexuais , Espectrometria de Massas por Ionização por Electrospray , Detecção do Abuso de Substâncias/métodosRESUMO
OBJECTIVES: In order to measure occupational exposure concentrations of ethyl tertiary-butyl ether (ETBE), we developed a diffusive sampling method for monitoring ETBE and performed an ETBE exposure assessment. METHODS: The applicability of diffusive samplers was examined by exposing the samplers to ETBE vapor in test chambers. The personal exposure levels of workers and airborne concentrations were measured at 4 gas stations. RESULTS: The ETBE sampling rate for the diffusive samplers (VOC-SD, Sigma-Aldrich Japan) was 25.04 ml/min (25°C). Compared with the active sampling method, the diffusive samplers could be used for short-term measurements and in environments containing a mixture of organic solvents. The geometric mean (GM) of TWA-8h ETBE was 0.08 ppm (0.02-0.28 ppm) in 28 gas station workers and 0.04 ppm (0.01-0.21 ppm) in 2 gasoline tanker truck drivers. With regard to ETBE airborne concentrations, the GM was 4.12 ppm (0.93-8.71 ppm) at the handles of hanging pumps but dropped to less than 0.01 ppm (less than 0.01-0.01 ppm) at the side of a public road. CONCLUSION: The diffusive sampling method can be used for the measurement of occupational ETBE exposure. The threshold limit of TLV-TWA 5 ppm recommended by the ACGIH was not exceeded in any of the workers in this study.
Assuntos
Poluentes Ocupacionais do Ar/análise , Etil-Éteres/análise , Veículos Automotores , Exposição Ocupacional/análise , Petróleo , Automóveis , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Humanos , Exposição por Inalação/análise , Exposição por Inalação/estatística & dados numéricos , Japão , Exposição Ocupacional/estatística & dados numéricosRESUMO
The gas chromatography method with direct injection for quantitative determination of residual nonvolatile solvents such as 2-(2-chloroethoxy)ethanol (CEE) and N-methyl-2-pyrrolidinone (NMP) in quetiapine--the pharmaceutical active substance has been validated. Validation was performed according to the requirement of ICH validation guidelines Q2A and Q2B. Specificity, precision, accuracy, linearity, limits of detection and quantitation and robustness were determined and excellent results were obtained.
Assuntos
Antipsicóticos/química , Cromatografia Gasosa , Dibenzotiazepinas/química , Contaminação de Medicamentos , Etil-Éteres/análise , Pirrolidinonas/análise , Solventes/análise , Tecnologia Farmacêutica/métodos , Química Farmacêutica , Cromatografia Gasosa/normas , Fumarato de Quetiapina , Reprodutibilidade dos Testes , Tecnologia Farmacêutica/normasRESUMO
Recently, many chemicals released into the environment have been shown to mimic endogenous hormones such as estradiol. It has been demonstrated that these compounds cause several adverse effects on wildlife and humans, such as the feminization of animal species, development of physical abnormalities and birth defects, and reproductive failure. In an effort to model the behaviour of some endocrine-disrupting chemicals (EDCs) and to establish the level of contamination in sewage samples, a quantitative method for the simultaneous determination of nonylphenol, octylphenol and corresponding ethoxylates (1-12), 17α-ethynylestradiol, bisphenol-A, and 17ß-estradiol and two of its metabolites have been developed. Identification and quantification were achieved by high performance liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS). Satisfactory detection limits (between 0.5-6 ng L(-1) in the dissolved phase and 1.4-12.7 ng g(-1) in the particulate phase) and analyte recoveries (between 60% and 108%) were achieved for target compounds. The optimised method was applied to the determination of EDCs in liquid sewage samples collected from a wastewater treatment plant (WWTP) in Las Palmas de Gran Canaria (Spain). Concentrations of EDCs ranged from <10 ng L(-1) to nearly 1200 ng L(-1) in the dissolved phase, and from 0.005 µg g(-1) to 2.8 µg g(-1) in the suspended particulate matter.
Assuntos
Disruptores Endócrinos/análise , Esgotos/análise , Poluentes Químicos da Água/análise , Compostos Benzidrílicos , Cromatografia Líquida , Estradiol/análise , Etinilestradiol/análise , Etil-Éteres/análise , Limite de Detecção , Fenóis/análise , Polímeros/análise , Extração em Fase Sólida , Espanha , Espectrometria de Massas em TandemRESUMO
Mineral surfaces form the main sorption phase for alcohol ethoxylates (AEs) in marine sediment. Competition for adsorption sites is investigated for marine sediment and kaolinite clay using simple mixtures of AE homologues. For both sorbents, adsorption sites on mineral surfaces can be effectively blocked by an AE homologue with the strongest adsorption affinity. The strongly adsorbed AE, however, forms a second sorption phase to which weakly adsorbing AE will sorb, forming bilayers. An extended dual-mode model accounts for competition effects, while still based on sorption properties of individual compounds. Competition effects become apparent when total adsorbed concentrations reach approximately 10% of the adsorption capacity. Deviations from individual sorption isotherms depend on affinity constants and dissolved homologue composition. Competition will not often occur in contaminated field sediments, with AEs concentrations usually far below the adsorption capacity, but will affect sorption studies, sediment toxicity tests or applications with nonionic surfactant mixtures.
Assuntos
Álcoois/análise , Etil-Éteres/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Absorção , Adsorção , Álcoois/química , Etil-Éteres/química , Cinética , Modelos Químicos , Medição de Risco , Água do Mar/química , Poluentes Químicos da Água/químicaRESUMO
The occurrence and persistence of anthropogenic pollutants in the environment showing estrogenic-endocrine modulating effects in aquatic organisms is a 'hot' issue of major health- and environment-related concern worldwide. The population growth and the increasing scarcity of water in many regions of the world have led to a comprehensive reuse of treated wastewater that, ultimately, may cause a long-term concentration buildup of many toxic persistent organic pollutants (POPs) in the closed cycle of water supply and wastewater treatment and reuse. The endocrinic/mutagenic potencies of the EDCs-branched chain alkylphenol ethoxylates (APEOs), polycyclic aromatic hydrocarbons (PAHs), and their metabolites are well-documented. From approximately 5.5 x 108 m3/y of sewage produced in Israel, approximately 70% are reused, following a conventional, or advanced, activated sludge or sand aquifer treatment (SAT). A major related question is: Does this practice conform to sustainability? Our studies reveal that (a) the concentrations of APEOs and PAHs in Israel rivers and sediments do pose a potential health risk problem; and (b) the synergistic ecotoxicologic impact of environmentally relevant mixtures of these POPs, in WWTP effluents, constitutes an inconsistency, healthwise, with sustainability practice.
Assuntos
Disruptores Endócrinos/análise , Etil-Éteres/análise , Água Doce/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Humanos , Israel , Eliminação de Resíduos Líquidos/métodosRESUMO
Analysis of volatile organic compounds (VOCs) provides an elegant approach for cancer screening and disease monitoring, whose use is currently limited by a lack of validated cancer-derived metabolites, which may serve as biomarkers. The aim of the experiments presented here was to investigate the release and consumption of VOCs from the non small cell lung cancer cell line NCI-H1666, which was originally derived from a bronchoalveolar carcinoma.Following detachment by trypsinization suspended cells were incubated in a sealed fermenter for 21 hours. 200 ml of headspace from the cell culture were sampled, diluted with dry, highly purified air and preconcentrated by adsorption on three different solid sorbents with increasing adsorption strength. VOC-analysis was performed by thermodesorption-gas chromatography mass spectrometry (TD-GC-MS). In contrast to our previous studies experiments with NCI-H1666 cells only confirmed the consumption of several aldehydes, n-butyl acetate and the ethers methyl tert-butyl ether and ethyl tert-butyl ether, but no unequivocal release of VOCs was observed. Together with our previously published work these data indicate that the consumption of certain VOCs is commonly observed while their release shows cell line-restricted patterns, whose underlying causes are unknown.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Compostos Orgânicos Voláteis/análise , Acetatos/análise , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Etil-Éteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espaço Intracelular/química , Neoplasias Pulmonares/patologia , Éteres Metílicos/análise , Concentração OsmolarRESUMO
Polysorbate surfactants (commercially available as Tween) are widely used in pharmaceutical, cosmetic and food products. They are generally considered as esters of ethoxylated sorbitan with fatty acids. Diffusion H1 NMR spectroscopy on a solution of polysorbate 20 in D2O revealed that only one diffusion coefficient was found for the fatty acyl part. Using the Stokes-Einstein equation, it became obvious that this diffusion behavior was caused by micelles. On the other hand, two significantly different diffusion coefficients were found for the methylene groups of ethylene oxide (EO). This indicates the presence of two distinct EO containing species in solution. Since the slowest diffusing EO species has the same diffusion coefficient as the fatty acyl part, it corresponds to the micellar (i.e. fatty acyl bound) ethoxylates. The diffusion coefficient of the fastest diffusing EO species was a factor of four larger than that of the slowly diffusing species and was attributed to water-soluble non-esterified ethoxylates. A solution of polysorbate 20 in the presence of NaOD was prepared to investigate if hydrolysis of the sorbitan ester could be the reason for the occurence of these hydrophilic ethoxylates. It was found that alkaline hydrolysis does lead to an increasing fraction of non-esterified ethoxylates, but is not the cause of its presence in untreated polysorbate samples since these species were also found in solutions of polyethylene glycol oleyl ether (commercially available as Brij), which are not susceptible to hydrolysis. Fractionation of the EO species present in polysorbate 20 into an amphiphilic and a hydrophilic fraction was only partly obtained by activated carbon adsorption. On the other hand, sequential extraction of aqueous polysorbate solutions by ethyl acetate and chloroform enabled a nearly complete fractionation. H1 NMR spectroscopy proved to be very useful since it allows in situ determination of the global composition of a surfactant sample, as well as quantification of both the amphiphilic and hydrophilic ethoxylate fractions via diffusion measurements.