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1.
J Expo Sci Environ Epidemiol ; 31(3): 476-486, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33958708

RESUMO

BACKGROUND: Certain types of hair products are more commonly used by Black women. Studies show hair products contain several endocrine-disrupting chemicals that are associated with adverse health outcomes. As chemical mixtures of endocrine disruptors, hair products may be hormonally active, but this remains unclear. OBJECTIVE: To assess the hormonal activity of commonly used Black hair products. METHODS: We identified six commonly used hair products (used by >10% of the population) from the Greater New York Hair Products Study. We used reporter gene assays (RGAs) incorporating natural steroid receptors to evaluate estrogenic, androgenic, progestogenic, and glucocorticoid hormonal bioactivity employing an extraction method using bond elution prior to RGA assessment at dilutions from 50 to 500. RESULTS: All products displayed hormonal activity, varying in the amount and effect. Three samples showed estrogen agonist properties at levels from 12.5 to 20 ng/g estradiol equivalent concentrations All but one sample showed androgen antagonist properties at levels from 20 to 25 ng/g androgen equivalent concentrations. Four samples showed antagonistic and agonistic properties to progesterone and glucocorticoid. SIGNIFICANCE: Hair products commonly used by Black women showed hormonal activity. Given their frequent use, exposure to hormonally active products could have implications for health outcomes and contribute to reproductive and metabolic health disparities.


Assuntos
Disruptores Endócrinos , Preparações para Cabelo , Negro ou Afro-Americano , Estrogênios , Feminino , Humanos , New York
2.
J AOAC Int ; 99(4): 878-889, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27455929

RESUMO

The main known groups of mycotoxins are aflatoxins, fumonisins, ochratoxins, type A trichothecenes (T-2 toxin and HT-2 toxin), type B trichothecenes (deoxynivalenol), and zearalenones. They are harmful to humans, domestic animals, and livestock. In Europe, maximum permitted limits for aflatoxin B1 are set, and guidance levels are recommended for the other mycotoxins. This study applied biochip array technology to semiquantitative multimycotoxin screening at different levels to facilitate the verification of the compliance of feed material with acceptable safety standards. This application was developed and validated based on European Commission Decision No. 2002/657/EC. After a single generic sample-preparation method, simultaneous competitive chemiluminescent immunoassays were used and applied to the Evidence Investigator analyzer. The r and within-laboratory R values showed low overall CVs (10.6 and 11.6%, respectively). Low matrix effect and, consequently, low decision limits and detection capabilities proved the high sensitivity of the technology. The overall average recovery was 104%. Samples (n = 16) investigated within the Food Analysis Performance Assessment Scheme (FAPAS) program showed excellent correlation to assigned values. FAPAS proficiency-testing feed samples (n = 10) were within the schemes' z-score ±2 range. The authentic feed samples survey showed excellent correlation with LC-MS/MS. This application is, therefore, reliable and represents an innovative, cost-effective, and multianalytical tool for mycotoxin screening.


Assuntos
Análise em Microsséries/métodos , Micotoxinas/análise , Ração Animal/análise , Contaminação de Alimentos/análise , Imunoensaio/métodos , Reprodutibilidade dos Testes
3.
Food Chem ; 159: 157-65, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24767039

RESUMO

Sports supplements are becoming a regular dietary addition for consumers who view such products as a means of improving their health and performance. Previously estrogenic endocrine disruptors (EDs) were detected in 80% of 116 sports supplements investigated by biological in vitro reporter gene assays (RGAs). The aim of this study was to quantify the hormonal activity in 50 of these sports supplement samples using a validated estrogen RGA and perform an exposure and risk assessment for human health. Results showed that 17ß-estradiol equivalent levels were higher than those reported as being present in the typical human omnivore diet in 33 of the sports supplements and higher than the acceptable daily intake (ADI) in 13 of these products. The highest activity samples presented a potential to influence the human daily exposure to 17ß-estradiol like activity in various risk groups with a predicted hormonal impact of greatest concern in young boys and postmenopausal women. In conclusion, consumers of sports supplements may be exposed to high levels of estrogenic EDs.


Assuntos
Suplementos Nutricionais/análise , Disruptores Endócrinos/análise , Estradiol/análise , Medição de Risco , Esportes , Adolescente , Adulto , Bioensaio/métodos , Criança , Suplementos Nutricionais/efeitos adversos , Feminino , Genes Reporter , Humanos , Masculino
4.
Food Chem ; 136(3-4): 1590-6, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23194567

RESUMO

A panel of reporter gene assays (RGAs) coupled with a single solid phase extraction (SPE) step was developed and used to screen bottled mineral water for the presence of four classes of endocrine disruptors (EDs), oestrogens, androgens, progestagens and glucocorticoids. Fourteen brands of bottled mineral water in triplicate (42 samples) were analysed. Overall, hormonal activity was found in 78% of the samples. Oestrogenic, androgenic, progestagenic and glucocorticoid activity was found in 38%, 38%, 36% and 55% of the samples, respectively at an average concentration of 10 ng/l 17ß-estradiol equivalent (EEQ), 26 ng/l testosterone equivalent (TEQ), 123 ng/l progesterone equivalent (PEQ) and 13.5 ng/l hydrocortisone equivalent (HEQ). The level of oestrogenic, androgenic and progestagenic activity observed is not considered a matter of concern for the consumers' health. It is unknown whether the glucocorticoid levels observed are safe. The ED source, long term exposure and mixture effects remain to be investigated.


Assuntos
Água Potável/análise , Disruptores Endócrinos/análise , Poluentes Químicos da Água/análise , Androgênios/análise , Estradiol/análise , Estrogênios/análise , Progesterona/análise , Testosterona/análise
5.
Anal Bioanal Chem ; 403(10): 3057-67, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22411538

RESUMO

Previously developed estrogen and androgen mammalian reporter gene assays (RGAs) were assessed for their potential use as a quantitative screening method in the detection of estrogenic and androgenic endocrine disruptors (EDs) in sport supplements. The validation of both RGAs coupled with dispersive solid phase extraction (dSPE) was performed in accordance with European Commission Decision EC/2002/6579 for biological screening methods. Decision limits (CCα) and detection capabilities (CCß) were established for both the estrogen and androgen RGAs. All samples were compliant with CCα and CCß in both bioassays. Recovery rates were 96 % for 17ß-estradiol and 115 % for dihydrotestosterone as obtained in their corresponding RGA. Both estrogens and androgens were stable in samples for more than 3 weeks, when stored at -20 °C. Specificity, good repeatability (coefficients of variation (CV), 12-25 %), reproducibility and robustness of both bioassays were also observed. Four different ED modes of action were determined for estrogens and androgens in 53 sport supplements, using the validated RGAs. This study revealed that 89 % of the investigated sport supplements contained estrogenic EDs and 51 % contained androgenic compounds. In conclusion, both bioassays are suitable for sport supplement screening of estrogenic and androgenic EDs.


Assuntos
Androgênios/análise , Androgênios/farmacologia , Suplementos Nutricionais/análise , Disruptores Endócrinos/análise , Disruptores Endócrinos/farmacologia , Genes Reporter , Esportes , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Extração em Fase Sólida , Relação Estrutura-Atividade
6.
Anal Chim Acta ; 700(1-2): 34-40, 2011 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-21742114

RESUMO

The increasing availability and use of sports supplements is of concern as highlighted by a number of studies reporting endocrine disruptor contamination in such products. The health food supplement market, including sport supplements, is growing across the Developed World. Therefore, the need to ensure the quality and safety of sport supplements for the consumer is essential. The development and validation of two reporter gene assays coupled with solid phase sample preparation enabling the detection of estrogenic and androgenic constituents in sport supplements is reported. Both assays were shown to be of high sensitivity with the estrogen and androgen reporter gene assays having an EC(50) of 0.01 ng mL(-1) and 0.16 ng mL(-1) respectively. The developed assays were applied in a survey of 63 sport supplements samples obtained across the Island of Ireland with an additional seven reference samples previously investigated using LC-MS/MS. Androgen and estrogen bio-activity was found in 71% of the investigated samples. Bio-activity profiling was further broken down into agonists, partial agonists and antagonists. Supplements (13) with the strongest estrogenic bio-activity were chosen for further investigation. LC-MS/MS analysis of these samples determined the presence of phytoestrogens in seven of them. Supplements (38) with androgen bio-activity were also selected for further investigation. Androgen agonist bio-activity was detected in 12 supplements, antagonistic bio-activity was detected in 16 and partial antagonistic bio-activity was detected in 10. A further group of supplements (7) did not present androgenic bio-activity when tested alone but enhanced the androgenic agonist bio-activity of dihydrotestosterone when combined. The developed assays offer advantages in detection of known, unknown and low-level mixtures of endocrine disruptors over existing analytical screening techniques. For the detection and identification of constituent hormonally active compounds the combination of biological and physio-chemical techniques is optimal.


Assuntos
Bioensaio/métodos , Suplementos Nutricionais/análise , Disruptores Endócrinos/análise , Genes Reporter , Antagonistas de Androgênios/análise , Antagonistas de Androgênios/isolamento & purificação , Androgênios/agonistas , Androgênios/análise , Androgênios/isolamento & purificação , Linhagem Celular , Disruptores Endócrinos/isolamento & purificação , Antagonistas de Estrogênios/análise , Antagonistas de Estrogênios/isolamento & purificação , Moduladores de Receptor Estrogênico/análise , Moduladores de Receptor Estrogênico/isolamento & purificação , Humanos , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Extração em Fase Sólida/métodos
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