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1.
Environ Res ; 175: 100-107, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31108353

RESUMO

BACKGROUND: The chemicals benzene, toluene, ethylbenzene, and xylenes (BTEX) are neuroactive. Exposures often co-occur because they share common sources. We examined neurologic effects of environmental BTEX exposure among U.S. Gulf coast residents taking into account concomitant exposures. METHODS: We measured blood concentrations of BTEX in 690 Gulf state residents. Neurologic symptoms were ascertained via telephone interview. We used log-binomial regression to estimate associations between blood BTEX levels and self-reported neurologic symptoms independently for the presence of any neurologic, central (CNS), or peripheral nervous system (PNS) symptoms. We estimated associations in single chemical models mutually adjusted for co-occurring BTEX and used weighted quantile sum regression to model associations between the combined BTEX mixture and neurologic symptoms. RESULTS: Half (49%) of participants reported at least one neurologic symptom. Each BTEX chemical was associated with increased CNS and PNS symptoms in single-chemical models comparing the highest to lowest quartile of exposure. After adjusting for coexposures, benzene was associated with CNS symptoms among all participants (PR = 2.13, 95% CI: 1.27, 3.57) and among nonsmokers (PR = 2.30, 95% CI: 1.35, 3.91). After adjusting for coexposures, associations with toluene were apparent only for reporting multiple PNS symptoms (PR = 2.00, 95% CI: 0.96, 4.16). In mixture analyses, a one-quartile increase in BTEX exposure was associated with neurologic symptoms (OR = 1.47, 95% CI: 1.11, 1.98). The weighted quantile sum index weighted benzene most heavily, which was consistent with single chemical analyses. CONCLUSIONS: Increasing blood benzene concentration was associated with increased prevalence of CNS symptoms. In this sample, BTEX-associated neurologic effects are likely driven by exposure to benzene and, to a lesser extent, toluene.


Assuntos
Exposição Ambiental , Hidrocarbonetos Aromáticos , Doenças do Sistema Nervoso , Poluição por Petróleo , Adulto , Benzeno/efeitos adversos , Benzeno/análise , Derivados de Benzeno/efeitos adversos , Derivados de Benzeno/sangue , Feminino , Humanos , Hidrocarbonetos Aromáticos/efeitos adversos , Hidrocarbonetos Aromáticos/sangue , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/epidemiologia , Fatores Socioeconômicos , Tolueno/efeitos adversos , Tolueno/sangue , Xilenos/efeitos adversos , Xilenos/sangue
2.
Talanta ; 198: 573-584, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30876601

RESUMO

Dynamic headspace sampling is an important technique for the analysis of consumer products, the study of biological samples and environmental water analyses. This paper shows the influence of experimental conditions, such as the sampling time, sampling flow rate, headspace volume, liquid volume and Henry coefficient on the measured average concentration values. A corresponding closed expression as function of these variables is introduced in order to quantify the deviation of the initial headspace concentration. The proposed bi-exponential function embeds different current existing models for recovery calculation in dynamic sampling analyses in one single expression. A fully automated and user-friendly Excel® file to investigate or to model the dynamic headspace sampling results is added to everyone's easy use.


Assuntos
Álcoois/sangue , Hidrocarbonetos Aromáticos/sangue , Simulação de Dinâmica Molecular , Polímeros/análise , Álcoois/química , Humanos , Hidrocarbonetos Aromáticos/química , Polímeros/química
3.
Environ Int ; 121(Pt 2): 1193-1203, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30376998

RESUMO

Physiologically-based toxicokinetic (PBTK) model has immense role to play in the risk assessment process due to specified mathematical representation of the absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) of chemicals in diverse environmental compartment. Determination of adipose/blood partition coefficient [logP(adipose/blood)] is regarded as one of the crucial constraints of PBTK models. In respect to the challenge for identifying the chemical-definite parameters for these models, especially within short time frame and with limited resources, quantitative structure-activity relationship (QSAR) models are beneficial for providing the chemical-specific parameters of PBTK models. In the present study, we have developed robust, statistically highly significant (R2 = 0.92, QLOO2 = 0.90, RPred2 = 0.92) and mechanistically interpretable three descriptors QSAR models for 67 environmental chemicals [Alcohols, polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzodioxins (PCDDs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs)] employing the experimental values of adipose/blood partition coefficient for human. The partitioning of chemicals into adipose tissue and blood offers information related to distribution and toxicological effects of these molecules in to the mammal system. The developed models are helpful to understand the mechanistic basis of toxicokinetic processes into the mammal system followed by risk assessment and risk management process. The applicability domain (AD) of the developed model was checked and followed by its employment to predict adipose/blood partition coefficient of 513 environmental contaminants consist of PCBs, PBDEs, PCDDs and PAHs from USA Environmental protection agency (US EPA) site.


Assuntos
Tecido Adiposo/metabolismo , Álcoois/metabolismo , Poluentes Ambientais/metabolismo , Hidrocarbonetos Aromáticos/metabolismo , Modelos Biológicos , Álcoois/sangue , Éteres Difenil Halogenados/metabolismo , Humanos , Hidrocarbonetos Aromáticos/sangue , Bifenilos Policlorados/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Relação Quantitativa Estrutura-Atividade , Medição de Risco
4.
Anal Sci ; 34(10): 1183-1188, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30305595

RESUMO

Aryl halides are a very important category of compounds that include many vital drugs and key industrial additives, such as clofibrate and bromobenzene, respectively. Due to their importance, our research group previously developed a novel fluorescence labeling approach for their analysis using a fluorescent aryl boronic acid as a reagent, based on the Suzuki coupling reaction. This coupling reaction was successfully applied for the determination of aryl halides in biological fluids; however, there was a limitation of low reactivity towards ortho-substituted aryl halides. In the present study, a novel fluorescence derivatization approach for aryl halides was developed using, 2-(4-ethynylphenyl)-4,5-diphenyl-1H-imidazole (DIB-ET) as a fluorescent alkyne reagent, based on the Sonogashira coupling reaction. DIB-ET reacted with aryl bromides in the presence of palladium and copper as catalysts, yielding fluorescent derivatives that could be subsequently determined by an HPLC system with fluorescence detection. The detection limits (S/N = 3) for aryl bromides were in the range of 14 - 23 nM, which is 3.5 - 18-times more sensitive than our previously developed approach, Suzuki coupling derivatization. Moreover, in contrast to the previous technique, the reactivity of DIB-ET to ortho-substituted aryl bromides was almost equivalent to that of the para-substituted aryl bromides. Hence, by using this newly developed approach we could label the aryl halides with more sensitivity and reactivity. Finally, the proposed method was successfully applied for the selective determination of aryl bromides in human serum with good recovery (84.6 - 107%), which proves the ability of the developed method to determine occupational exposure to aryl halides.


Assuntos
Alcinos/química , Bromo/química , Corantes Fluorescentes/química , Hidrocarbonetos Aromáticos/química , Humanos , Hidrocarbonetos Aromáticos/sangue
5.
J Expo Sci Environ Epidemiol ; 28(4): 358-370, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29288257

RESUMO

To address concerns among Gulf Coast residents about ongoing exposures to volatile organic compounds, including benzene, toluene, ethylbenzene, o-xylene, and m-xylene/p-xylene (BTEX), we characterized current blood levels and identified predictors of BTEX among Gulf state residents. We collected questionnaire data on recent exposures and measured blood BTEX levels in a convenience sample of 718 Gulf residents. Because BTEX is rapidly cleared from the body, blood levels represent recent exposures in the past 24 h. We compared participants' levels of blood BTEX to a nationally representative sample. Among nonsmokers we assessed predictors of blood BTEX levels using linear regression, and predicted the risk of elevated BTEX levels using modified Poisson regression. Blood BTEX levels in Gulf residents were similar to national levels. Among nonsmokers, sex and reporting recent smoky/chemical odors predicted blood BTEX. The change in log benzene was -0.26 (95% CI: -0.47, -0.04) and 0.72 (0.02, 1.42) for women and those who reported odors, respectively. Season, time spent away from home, and self-reported residential proximity to Superfund sites (within a half mile) were statistically associated with benzene only, however mean concentration was nearly an order of magnitude below that of cigarette smokers. Among these Gulf residents, smoking was the primary contributor to blood BTEX levels, but other factors were also relevant.


Assuntos
Hidrocarbonetos Aromáticos/sangue , Fumar/sangue , Compostos Orgânicos Voláteis/sangue , Adulto , Benzeno , Monitoramento Ambiental/métodos , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estações do Ano , Sudeste dos Estados Unidos , Inquéritos e Questionários , Tolueno , Adulto Jovem
6.
Biomarkers ; 20(6-7): 391-403, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26554277

RESUMO

A randomized, multi-center study of adult cigarette smokers switched to tobacco-heating cigarettes, snus or ultra-low machine yield tobacco-burning cigarettes (50/group) was conducted, and subjects' experience with the products was followed for 24 weeks. Differences in biomarkers of tobacco exposure between smokers and never smokers at baseline and among groups relative to each other and over time were assessed. Results indicated reduced exposure to many potentially harmful constituents found in cigarette smoke following product switching. Findings support differences in exposure from the use of various tobacco products and are relevant to the understanding of a risk continuum among tobacco products (ClinicalTrials.gov Identifier: NCT02061917).


Assuntos
Biomarcadores/sangue , Biomarcadores/urina , Prevenção do Hábito de Fumar , Dispositivos para o Abandono do Uso de Tabaco/estatística & dados numéricos , Abandono do Uso de Tabaco/métodos , Tabaco sem Fumaça/estatística & dados numéricos , Adulto , Aminas/sangue , Aminas/urina , Feminino , Humanos , Hidrocarbonetos Aromáticos/sangue , Hidrocarbonetos Aromáticos/urina , Masculino , Pessoa de Meia-Idade , Nicotina/sangue , Nicotina/urina , Fatores de Tempo
7.
Gig Sanit ; (2): 23-6, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25051733

RESUMO

In children residing in areas with a high content of a number of aromatic hydrocarbons in ambient air and organochlorine compounds in drinking water there were studied the blood levels of these compounds, as well as the assessment of the indices of the immune and neuroendocrine systems was performed. The higher blood content of phenol and formaldehyde has been established and there was identified an array of organochlorine and aromatic compounds not detected in the control group children. In the blood of the children of a study group there was found an imbalance of indices of cellular components of innate and adaptive immunity, pro- and anti-inflammatory cytokines, as well as increased concentrations of free thyroxine and serotonin in the blood serum, which indicates to a change in the functions of regulatory systems in children exposed to organochlorine and aromatic compounds.


Assuntos
Água Potável/análise , Exposição Ambiental/análise , Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos Clorados/análise , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Criança , Pré-Escolar , Sistema Endócrino/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Feminino , Humanos , Hidrocarbonetos Aromáticos/efeitos adversos , Hidrocarbonetos Aromáticos/sangue , Hidrocarbonetos Clorados/efeitos adversos , Hidrocarbonetos Clorados/sangue , Sistema Imunitário/efeitos dos fármacos , Masculino , Federação Russa/epidemiologia
9.
Med Tr Prom Ekol ; (12): 30-3, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23461187

RESUMO

Workers exposed to aromatic hydrocarbons appeared to have prevalence of heterozygous variants of CYP1A1 gene (9893 A/G) and tumor necrosis factor gene reliably higher vs. the reference group 2.5 and 3.3 times respectively, and level of anti-benzene antibodies (IgG) increased vs. the reference group. The data presented demonstrate negative immunogenetic associations of aromatic hydrocarbons influence on oil extraction operators.


Assuntos
Citocromo P-450 CYP1A1/genética , Hidrocarbonetos Aromáticos , Tolerância Imunológica/efeitos dos fármacos , Imunoglobulina E/sangue , Exposição Ocupacional/efeitos adversos , Fator de Necrose Tumoral alfa/genética , Adulto , Biomarcadores/sangue , Biotransformação/efeitos dos fármacos , Indústrias Extrativas e de Processamento , Feminino , Marcadores Genéticos , Humanos , Hidrocarbonetos Aromáticos/sangue , Hidrocarbonetos Aromáticos/toxicidade , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Masculino , Monitorização Imunológica/métodos , Polimorfismo Genético/efeitos dos fármacos
10.
Forensic Sci Int ; 217(1-3): 71-5, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22019392

RESUMO

Volatile hydrocarbons in post-mortem blood from victims of fires were analyzed quantitatively by headspace gas chromatography mass spectrometry. The benzene and styrene concentrations in the blood were positively correlated with the carboxyhemoglobin (CO-Hb) concentration, which is evidence that the deceased inhaled the hydrocarbons and carbon monoxide simultaneously. By contrast, the concentrations of toluene and CO-Hb in the blood were not significantly correlated. This lack of correlation could be explained by two different sources of toluene, with low blood concentrations of toluene arising when the deceased inhaled smoke and high blood concentrations of toluene arising when the deceased inhaled petroleum vapor or other unknown vapors. The quantity of soot deposited in the respiratory tract was classified into four grades (-, 1+, 2+, 3+). The mean CO-Hb concentration in the 1+ soot group was significantly lower than those in the 2+ (p<0.05) and 3+ (p<0.01) soot groups. The blood CO-Hb concentrations in the 1+ soot group were all below 30%. Those indicated that the deceased aspirated smoke that contained both soot and carbon monoxide. The wide variation in CO-Hb concentrations for each soot classification could be caused by the different types of smoke produced by different materials. For example, petroleum combustion with a limited supply of oxygen, like in a compartment fire, may produce a large volume of dense black smoke that contains a large quantity of soot. Soot deposits in the airways and the blood CO-Hb concentration are basic and essential autopsy findings that are used to investigate fire-related deaths. The quantitative GC-MS analysis of blood volatile hydrocarbons can provide additional useful information on the cause of the fire and the circumstances surrounding the death. In combination, these three findings are useful for the reconstruction of cases.


Assuntos
Incêndios , Hidrocarbonetos Aromáticos/sangue , Sistema Respiratório/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alcanos/análise , Carboxihemoglobina/análise , Carcinógenos/análise , Feminino , Patologia Legal , Cromatografia Gasosa-Espectrometria de Massas , Gasolina , Humanos , Querosene , Masculino , Pessoa de Meia-Idade , Sistema Respiratório/química , Lesão por Inalação de Fumaça/patologia , Fuligem/análise , Adulto Jovem
11.
Med Tr Prom Ekol ; (11): 8-11, 2011.
Artigo em Russo | MEDLINE | ID: mdl-22288180

RESUMO

Federal Research Center of Medical and preventive technologies of risk management to public health: in this paper, we present the results of aromatic hydrocarbons biomonitoring in blood of oil-producing industry workers.


Assuntos
Hidrocarbonetos Aromáticos/sangue , Exposição Ocupacional/análise , Petróleo , Monitoramento Ambiental/métodos , Indústrias Extrativas e de Processamento/métodos , Humanos , Hidrocarbonetos Aromáticos/efeitos adversos , Exposição Ocupacional/efeitos adversos , Petróleo/efeitos adversos
12.
Environ Res ; 109(4): 495-502, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19278675

RESUMO

Human biomonitoring provides an integrated measure for individual exposure to environmental pollutants. Better insight in inter-individual variability of biomarkers of exposure may help in the interpretation of biomonitoring studies. The aim was to study the impact of outliers, determine the optimal unit for fat-soluble biomarkers in serum and quantify the major determinants for biomarkers of exposure to polychlorinated aromatic hydrocarbons (PCAHs) in three age groups. Data were obtained from the Flemish Environment and Health Study (2002-2006). Marker PCBs (sum of 138, 153, 180), hexachlorobenzene (HCB) and p,p'-DDE were measured in cord blood samples of 1196 newborns, in serum samples of 1679 adolescents (14-15 years) and 1583 adults (50-65 years). Exclusion of influential outliers in multiple linear regression models lead to models that are better applicable to the general population. In terms of adjusted R2, the regression model with the pollutant expressed in volume-based units and blood fat as a separate independent variable was superior compared to models with other units. We found highly consistent relationships between the serum concentration of PCAHs and blood fat, age, changes in body weight, animal fat in the diet, local vegetable consumption (HCB and p,p'-DDE only) and being breastfed as a baby (in adolescents only). The impact of sex and BMI differed by age. For biomarkers of persistent pollutants that reflect long-term exposure, the relation between the covariates and the biomarkers can be well quantified.


Assuntos
Dieta , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos Aromáticos/sangue , Hidrocarbonetos Clorados/sangue , Metabolismo dos Lipídeos/fisiologia , Tecido Adiposo/química , Adolescente , Fatores Etários , Idoso , Bélgica/epidemiologia , Biomarcadores/sangue , Índice de Massa Corporal , Aleitamento Materno , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/metabolismo , Monitoramento Epidemiológico , Feminino , Humanos , Lactente , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores Sexuais
13.
J Expo Sci Environ Epidemiol ; 18(4): 421-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18059425

RESUMO

The relationships between levels of volatile organic compounds (VOCs) in blood and air have not been well characterized in the general population where exposure concentrations are generally at parts per billion levels. This study investigates relationships between the levels of nine VOCs, namely, benzene, chloroform, 1,4-dichlorobenzene, ethylbenzene, methyl tert-butyl ether (MTBE), tetrachloroethene, toluene, and m-/p- and o-xylene, in blood and air from a stratified random sample of the general US population. We used data collected from 354 participants, including 89 smokers and 265 nonsmokers, aged 20-59 years, who provided samples of blood and air in the National Health and Nutrition Examination Survey (NHANES) 1999-2000. Demographic and physiological characteristics were obtained from self-reported information; smoking status was determined from levels of serum cotinine. Multiple linear regression models were used to investigate the relationships between VOC levels in air and blood, while adjusting for effects of smoking and demographic factors. Although levels of VOCs in blood were positively correlated with the corresponding air levels, the strength of association (R(2)) varied from 0.02 (ethylbenzene) to 0.68 (1,4-DCB). Also the blood-air relationships of benzene, toluene, ethylbenzene, and the xylenes (BTEX) were influenced by smoking, exposure-smoking interactions, and by gender, age, and BMI, whereas those of the other VOCs were not. Interestingly, the particular exposure-smoking interaction for benzene was different from those for toluene, ethylbenzene, and the xylenes. Whereas smokers retained more benzene in their blood at increasing exposure levels, they retained less toluene, ethylbenzene, and xylenes at increasing exposure levels. Investigators should consider interaction effects of exposure levels and smoking when exploring the blood-air relationships of the BTEX compounds in the general population.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Atmosféricos/sangue , Exposição Ambiental/análise , Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos Aromáticos/sangue , Adulto , Fatores de Confusão Epidemiológicos , Monitoramento Ambiental/métodos , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Compostos Orgânicos/análise , Compostos Orgânicos/sangue , Fatores de Risco , Fumar/sangue , Estados Unidos
14.
Toxicol Lett ; 108(2-3): 241-7, 1999 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-10511268

RESUMO

A quasi-experimental field study was carried out in 24 volunteers with the aim of: (i) assessing personal exposure to aromatic hydrocarbons polluting urban areas; and (ii) exploring the role of polymorphic enzymes relevant to the biotransformation of benzene in the inter-individual variability of biomarkers. Each subject covered by bicycle: (i) inner city routes with often jammed traffic; and (ii) open rural routes. Time-weighted average airborne concentrations of benzene, toluene, ethylbenzene and xylenes (BTEX) were determined during 2-h runs. BTEX were determined by solid-phase micro-extraction (SPME) followed by gas chromatography coupled with mass spectrometry (GC-MS) in blood and spot urine samples collected just before and immediately after the runs. Urinary t,t-muconic acid was measured by high performance liquid chromatography (HPLC)-UV. Genotypes of epoxide hydrolase (EH) and glutathione-S-transferase class mu-1 (GSTM1) were also characterised. As compared to pre-run values, benzene and toluene in blood, and toluene and xylenes in urine significantly increased after urban runs. Urinary t,t-muconic acid was significantly higher in post-run samples after both urban (P < 0.001) and rural runs (P < 0.05). Despite a narrow range of exposure levels, a significant relationship was observed between airborne benzene and post-run t,t-muconic acid (r2 = 0.349, P < 0.00). When subgroups were distinguished according to EH and GSTM, subjects bearing both the EH wild type and GSTM 'null' genotype showed significant exposure-related changes in t,t-muconic acid excretion. Even at very low exposure levels, a 2-h bike run in a polluted urban environment may give rise to measurable changes in biomarkers of internal dose of selected aromatic hydrocarbons. Genetically-based metabolic differences may account for part of the inter-individual variability of biomarkers of exposure.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Hidrocarbonetos Aromáticos/análise , Adulto , Benzeno/análise , Derivados de Benzeno/sangue , Ciclismo , Biomarcadores/sangue , Biomarcadores/urina , Feminino , Humanos , Hidrocarbonetos Aromáticos/sangue , Masculino , Saúde da População Rural , Fatores Sexuais , Ácido Sórbico/análogos & derivados , Ácido Sórbico/análise , Tolueno/sangue , Saúde da População Urbana , Xilenos/sangue
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