Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
J Am Assoc Lab Anim Sci ; 58(2): 190-196, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30646968

RESUMO

Accidental exposure of our mice to bisphenol A (BPA) from damaged polycarbonate cages 20 y ago provided some of the first evidence of the harmful effects of exposure to this common chemical. Recently we found that housing mice in damaged polysulfone cages resulted in similar harmful effects due to exposure to bisphenol S (BPS). This problem was unexpected for 2 reasons. First, polysulfone is a far more chemically resistant polymer than polycarbonate. Second, BPS is not a component in the manufacture of polysulfone. We report here our efforts to verify the source of the BPS and eliminate the exposure. Our analysis of new polysulfone caging materials confirmed that BPS is a breakdown product of damaged polysulfone plastic. Furthermore, we found that BPS can cross-contaminate new or undamaged cages in facilities that process damaged caging materials. Neither the use of disposable cages nor replacement of caging materials used solely for our colony was sufficient to eliminate exposure effects. Only the replacement of all cages and water bottles in the facility corrected the problem and allowed us to resume our studies. Taken together, our previous and current findings underscore the concern that chemicals from plastics are harmful environmental contaminants for both humans and animals. Furthermore, our results provide strong evidence that the presence of damaged plastic in a facility may be sufficient to affect research results and, by exten- sion, animal health.


Assuntos
Abrigo para Animais , Plásticos/química , Animais , Exposição Ambiental , Humanos , Ciência dos Animais de Laboratório , Camundongos , Plásticos/toxicidade , Polímeros/química , Sulfonas/química
2.
J Expo Sci Environ Epidemiol ; 28(2): 101-108, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29019345

RESUMO

The use and advantages of high-resolution mass spectrometry (MS) as a discovery tool for environmental chemical monitoring has been demonstrated for environmental samples but not for biological samples. We developed a method using liquid chromatography-quadrupole time-of-flight MS (LC-QTOF/MS) for discovery of previously unmeasured environmental chemicals in human serum. Using non-targeted data acquisition (full scan MS analysis) we were able to screen for environmental organic acids (EOAs) in 20 serum samples from second trimester pregnant women. We define EOAs as environmental organic compounds with at least one dissociable proton which are utilized in commerce. EOAs include environmental phenols, phthalate metabolites, perfluorinated compounds, phenolic metabolites of polybrominated diphenyl ethers and polychlorinated biphenyls, and acidic pesticides and/or predicted acidic pesticide metabolites. Our validated method used solid phase extraction, reversed-phase chromatography in a C18 column with gradient elution, electrospray ionization in negative polarity and automated tandem MS (MS/MS) data acquisition to maximize true positive rates. We identified "suspect EOAs" using Agilent MassHunter Qualitative Analysis software, to match chemical formulas generated from each sample run with molecular formulas in our unique database of 693 EOAs assembled from multiple environmental literature sources. We found potential matches for 282 (41%) of the EOAs in our database. Sixty-five of these suspect EOAs were detected in at least 75% of the samples; only 19 of these compounds are currently biomonitored in National Health and Nutrition Examination Survey. We confirmed two of three suspect EOAs by LC-QTOF/MS using a targeted method developed through LC-MS/MS, reporting the first confirmation of benzophenone-1 and bisphenol S in pregnant women's sera. Our suspect screening workflow provides an approach to comprehensively scan environmental chemical exposures in humans. This can provide a better source of exposure information to help improve exposure and risk evaluation of industrial chemicals.


Assuntos
Ácidos/análise , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Compostos Orgânicos/análise , Soro/química , Benzofenonas/análise , Cromatografia Líquida/métodos , Cromatografia de Fase Reversa , Bases de Dados Factuais , Feminino , Humanos , Espectrometria de Massas/métodos , Fenóis/análise , Gravidez , Segundo Trimestre da Gravidez , Reprodutibilidade dos Testes , Sulfonas/análise , Espectrometria de Massas em Tandem
3.
Environ Health ; 15: 50, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27071747

RESUMO

BACKGROUND: Bisphenol A (BPA) is a ubiquitous, endocrine-disrupting environmental contaminant that increases risk of some adverse developmental effects. Thus, it is important to characterize BPA levels, metabolic fate and sources of exposure in pregnant women. METHODS: We used an improved liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytic method to directly and simultaneously measure unconjugated BPA (uBPA), BPA glucuronide and BPA sulfate in the urine of a population of ethnically and racially diverse, and predominately low-income pregnant women (n = 112) in their second trimester. We also administered a questionnaire on dietary and non-dietary sources of exposure to BPA. RESULTS: We found universal and high exposure to uBPA and its metabolites: median concentrations were 0.25, 4.67, and 0.31 µg/g creatinine for uBPA, BPA glucuronide, and BPA sulfate, respectively. The median Total BPA (uBPA + BPA in glucuronide and sulfate forms) level was more than twice that measured in U.S. pregnant women in NHANES 2005-2006, while 30 % of the women had Total BPA levels above the 95th percentile. On average, Total BPA consisted of 71 % BPA in glucuronide form, 15 % BPA in sulfate form and 14 % uBPA, however the proportion of BPA in sulfate form increased and the proportion of uBPA decreased with Total BPA levels. Occupational and non-occupational contact with paper receipts was positively associated with BPA in conjugated (glucuronidated + sulfated) form after adjustment for demographic characteristics. Recent consumption of foods and beverages likely to be contaminated with BPA was infrequent among participants and we did not observe any positive associations with BPA analyte levels. CONCLUSION: The high levels of BPA analytes found in our study population may be attributable to the low-income status of the majority of participants and/or our direct analytic method, which yields a more complete evaluation of BPA exposure. We observed near-universal exposure to BPA among pregnant women, as well as substantial variability in BPA metabolic clearance, raising additional concerns for effects on fetal development. Our results are consistent with studies showing thermal paper receipts to be an important source of exposure, point to the difficulty pregnant women have avoiding BPA exposure on an individual level, and therefore underscore the need for changes in BPA regulation and commerce.


Assuntos
Compostos Benzidrílicos/urina , Disruptores Endócrinos/urina , Poluentes Ambientais/urina , Glucuronídeos/urina , Fenóis/urina , Sulfatos/urina , Adolescente , Adulto , Estudos Transversais , Dieta , Monitoramento Ambiental , Feminino , Humanos , Exposição Materna , Pessoa de Meia-Idade , Pobreza , Gravidez , Inquéritos e Questionários , Adulto Jovem
4.
Am J Emerg Med ; 33(7): 985.e5-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25687617

RESUMO

UNLABELLED: Ibogaine, a psychotropic indole alkaloid, is gaining popularity among medical subcultures for its purported anti addictive properties. Its use has been associated with altered mental status, ataxia, gastrointestinal distress, ventricular arrhythmias, and sudden and unexplained deaths.Its pharmacokinetics in toxic states is not well understood. Case report:A 33-year-old man overdosed on ibogaine in an attempt to quit his use of heroin. He developed altered state of consciousness, tremor, ataxia,nausea, vomiting, and transient QT interval prolongation, which all remitted as he cleared the substance. Ibogaine was confirmed in his urine and serum with a peak serum concentration of 377 ng/mL. Nonlinear elimination kinetics and a formula match to its active metabolite noriobgaine were observed as well. CONCLUSION: This case presents the unique description of serial serum concentrations as well as urine and product-confirmed ibogaine toxicity with transient toxin-related QT interval prolongation.


Assuntos
Substâncias Controladas , Alucinógenos/intoxicação , Ibogaína/intoxicação , Adulto , Substâncias Controladas/sangue , Substâncias Controladas/urina , Tráfico de Drogas , Alucinógenos/sangue , Alucinógenos/farmacocinética , Alucinógenos/urina , Humanos , Ibogaína/sangue , Ibogaína/farmacocinética , Ibogaína/urina , Internet , Masculino
5.
J Occup Environ Med ; 56(8): 834-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25099409

RESUMO

OBJECTIVE: We sought to quantify absorption of triclosan, a potential endocrine disruptor, in health care workers with occupational exposure to soap containing this chemical. METHODS: A cross-sectional convenience sample of two groups of 38 health care workers at separate inpatient medical centers: hospital 1 uses 0.3% triclosan soap in all patient care areas; hospital 2 does not use triclosan-containing products. Additional exposure to triclosan-containing personal care products was assessed through a structured questionnaire. Urine triclosan was quantified and the occupational contribution estimated through regression modeling. RESULTS: Occupational exposure accounted for an incremental triclosan burden of 206 ng/mL (P = 0.02), while triclosan-containing toothpaste use was associated with 146 ng/mL higher levels (P < 0.001). CONCLUSIONS: Use of triclosan-containing antibacterial soaps in health care settings represents a substantial and potentially biologically relevant source of occupational triclosan exposure.


Assuntos
Anti-Infecciosos Locais/metabolismo , Exposição Ocupacional , Absorção Cutânea , Sabões/química , Triclosan/metabolismo , Adulto , Carga Corporal (Radioterapia) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cremes Dentais/química , Triclosan/urina
6.
Environ Sci Technol ; 47(21): 12477-85, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23941471

RESUMO

Bisphenol-A (BPA) is an endocrine disrupting chemical used in numerous consumer products, resulting in universal exposure in the United States. Prenatal exposure to BPA is associated with numerous reproductive and developmental effects in animals. However, little is known about human fetal exposure or metabolism of BPA during midgestation. In the present study, we present a new liquid chromatography-tandem mass spectrometry method to directly measure concentrations of BPA and two predominant metabolic conjugates-BPA glucuronide and BPA sulfate-in umbilical cord serum collected from elective second trimester pregnancy terminations. We detected at least one form of BPA in all umbilical cord serum samples: BPA (GM 0.16, range

Assuntos
Compostos Benzidrílicos/sangue , Glucuronídeos/sangue , Fenóis/sangue , Ésteres do Ácido Sulfúrico/sangue , Cordão Umbilical/metabolismo , Adolescente , Adulto , Animais , California , Cromatografia Líquida , Poluentes Ambientais/sangue , Feminino , Feto/metabolismo , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Gravidez , Padrões de Referência , Reprodutibilidade dos Testes , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA