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1.
Steroids ; 193: 109199, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36796473

RESUMEN

From 2012 to 2013, approximately 16 New York residents reported vague, nonspecific adverse health effects which included fatigue, loss of scalp hair, and muscle aches. One patient was hospitalized for liver damage. An epidemiological investigation identified a common factor among these patients; the consumption of B-50 vitamin and multimineral supplements from the same supplier. To investigate whether these nutritional supplements might have been responsible for the adverse health effects observed, comprehensive chemical analyses of marketed lots of the supplements were performed. To determine presence of organic components and contaminants, organic extracts of samples were prepared and analyzed using gas chromatography-mass spectrometry (GC-MS), liquid chromatography-tandem mass spectrometry (LC-MS/MS), liquid chromatography high-resolution mass spectrometry (LC-HRMS), and nuclear magnetic resonance (NMR). These analyses revealed the presence of significant levels of methasterone (17ß-hydroxy-2α,17α-dimethyl-5α-androstane-3-one), an androgenic steroid and schedule III-controlled substance; dimethazine, an azine-linked dimer of methasterone; and methylstenbolone (2,17α-dimethyl-17ß-hydroxy-5α-androst-1-en-3-one), a related androgenic steroid. Methasterone and extracts of certain supplement capsules were identified as highly androgenic in luciferase assays by using an androgen receptor promoter construct. This androgenicity persisted for several days after cell exposure to the compounds. The presence of these components in implicated lots were associated with adverse health effects and the hospitalization of one patient and the presentation of symptoms of severe virilization in a child. These findings underscore the need for more rigorous oversight of the nutritional supplement industry.


Asunto(s)
Anabolizantes , Doping en los Deportes , Niño , Humanos , Cromatografía de Gases y Espectrometría de Masas/métodos , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Andrógenos/efectos adversos , Suplementos Dietéticos/efectos adversos , Suplementos Dietéticos/análisis
2.
Artículo en Inglés | MEDLINE | ID: mdl-34741935

RESUMEN

Rodenticides are toxic chemicals used to control rodent populations and are among the most common household toxicants. Ingestion of foods contaminated with rodenticides may cause severe illness or death in humans and animals. A rapid analytical method was developed for the identification of nine common rodenticides in foods using solid-liquid extraction followed by dispersive-solid phase extraction prior to the analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and UV detection. The method validation on a variety of food matrices including cornmeal, peanut, whole wheat flour and pork liver produced average recoveries between 91.2 and 107% with relative standard deviations between 2.6 and 14% for all studied rodenticides. The method detection limits ranged from 2.7 to 8.2 µg/kg (ppb) for eight rodenticides analyzed by LC-MS/MS and between 0.10 and 0.21 mg/kg (ppm) for bromethalin which was analyzed by LC with UV detection. This method could be useful in preparedness for emergency response situations involving widespread food contamination, terrorist acts or for forensic studies.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Harina/análisis , Contaminación de Alimentos/análisis , Hígado/química , Rodenticidas/análisis , Rodenticidas/aislamiento & purificación , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Animales , Porcinos , Triticum/química
3.
Artículo en Inglés | MEDLINE | ID: mdl-29883891

RESUMEN

The objectives of this study were to develop and validate a method for the identification of toxic organic chemicals, including groups of controlled substances, alkaloids and pesticides that are highly toxic and considered threats to public health. This project aims to ensure our laboratory's readiness to respond to emergencies involving our food supply in cooperation with the Food Emergency Response Network (FERN) program. The food matrices were homogenized in a blender or food processor prior to extraction with an acetonitrile-water mixture using a QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure. The extracts were then analyzed by either gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-electrospray tandem mass spectrometry (LC-ESI/MS/MS). Method validation was performed on a variety of food matrices including lettuce, grapes, milk, chicken, pork and beef. MDLs for the toxic compounds ranged from 0.01 to 0.66 mg/kg (ppm). The findings in this study will provide a valuable resource for the determination of toxic chemicals in food matrices for emergency response situations.


Asunto(s)
Contaminación de Alimentos/análisis , Plaguicidas/análisis , Extracción en Fase Sólida/métodos , Alcaloides/análisis , Alcaloides/química , Alcaloides/aislamiento & purificación , Cromatografía Liquida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Plaguicidas/química , Plaguicidas/aislamiento & purificación , Espectrometría de Masas en Tándem/métodos
4.
J AOAC Int ; 97(1): 232-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24672883

RESUMEN

Contamination of drinking water by ethylene glycol (EG) is a public health concern. EG causes adverse health effects in humans and animals, including cardiopulmonary and acute renal failure. EG and other glycols, such as propylene glycol (PG) are major components in antifreeze liquids, which may be the main source of contamination of ground water. A sensitive LC/electrospray ionization (ESI)-MS/MS method was developed to measure trace amounts of EG, diethylene glycol, and 1,2- and 1,3-PG in several water sources, including municipal tap, lake, river, and salinated water. In this method, glycols in water samples were derivatized with benzoyl chloride by the Schotten-Baumann reaction, followed by liquid-liquid extraction using pentane as the organic solvent prior to the LC/ESI-MS/MS determination. QC included analysis of a method blank and samples fortified at low and high levels. Analytical data showed excellent linear calibration for all observed glycols, with good precision and accuracy. The method detection limits for the studied glycols ranged from 1.9 to 6.1 ng/mL across the water matrixes tested. This method is suitable to help assess water quality in areas that may be prone to glycol contamination.


Asunto(s)
Cromatografía Liquida/métodos , Glicol de Etileno/química , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/química , Agua/química , Aeropuertos , Agua Potable/química , Monitoreo del Ambiente/métodos , Agua Dulce/química
5.
J Agric Food Chem ; 58(1): 101-7, 2010 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-19904985

RESUMEN

The recent worldwide shortage of acetonitrile has prompted the development of a new method using methanol as an alternative organic solvent in the extraction and liquid chromatographic analysis of melamine and cyanuric acid that may be present as contaminants in dairy products and pet foods. A simple extraction of melamine and cyanuric acid residues in fortified samples was successfully achieved, using a methanol-water mixture and analysis by isotopic dilution high-performance liquid chromatography-triple-quadrupole mass spectrometry (HPLC-MS/MS). A two-step centrifugation procedure was employed to remove matrix components from extracts. The separation of melamine and cyanuric acid was carried out on a Dionex Acclaim Trinity P1 column, with a methanol and ammonium acetate buffer used as the mobile phase. Excellent linearity was achieved for both the melamine and cyanuric acid calibrations. A variety of dairy products and pet foods were fortified with melamine and cyanuric acid at three levels, 1, 2.5, and 10 microg/g, producing recovery yields of 101-119% for melamine and 84-123% for cyanuric acid. The lower limit of quantification (LLOQ) of melamine was 0.03 microg/g for liquid milk and 0.05 microg/g for dry infant milk formula. The quantitative results were comparable with those derived from previous methods that have been proposed by the U.S. Food and Drug Administration for the screening of melamine and its analogues in foods.


Asunto(s)
Alimentación Animal/análisis , Fraccionamiento Químico/métodos , Productos Lácteos/análisis , Contaminación de Alimentos/análisis , Metanol/química , Triazinas/análisis , Animales , Bovinos
6.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(24): 2499-505, 2009 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-19577523

RESUMEN

Mitragynine is the primary active alkaloid extracted from the leaves of Mitragyna speciosa Korth, a plant that originates in South-East Asia and is commonly known as kratom in Thailand. Kratom has been used for many centuries for their medicinal and psychoactive qualities, which are comparable to that of opiate-based drugs. Kratom abuse can lead to a detectable content of mitragynine residue in urine. Ultra trace amount of mitragynine in human urine was determined by a high performance liquid chromatography coupled to an electrospray tandem mass spectrometry (HPLC-ESI/MS/MS). Mitragynine was extracted by methyl t-butyl ether (MTBE) and separated on a HILIC column. The ESI/MS/MS was accomplished using a triple quadrupole mass spectrometer in positive ion detection and multiple reactions monitoring (MRM) mode. Ajmalicine, a mitragynine's structure analog was selected as internal standard (IS) for method development. Quality control (QC) performed at three levels 0.1, 1 and 5 ng/ml of mitragynine in urine gave mean recoveries of 90, 109, and 98% with average relative standard deviation of 22, 12 and 16%, respectively. The regression linearity of mitragynine calibration ranged from 0.01 to 5.0 ng/ml was achieved with correlation coefficient greater than 0.995. A detection limit of 0.02 ng/ml and high precision data within-day and between days analysis were obtained.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Drogas Ilícitas/orina , Alcaloides de Triptamina Secologanina/orina , Detección de Abuso de Sustancias/métodos , Espectrometría de Masas en Tándem/métodos , Humanos
7.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(11-12): 1109-16, 2009 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19328048

RESUMEN

Optimization of analytical instrumentation is essential when analyses of persistent organic pollutants in human serum are performed at ultra-trace levels. This research describes the analysis of polychlorinated biphenyls (PCBs) in serum using gas chromatography coupled with a mass selective detector (GC/MSD) in the selected ion monitoring (SIM) mode. We selected PCB-58 and PCB-186 as internal standards (ISs) for the method development, and newborn calf serum (NCS) was chosen as the matrix. The matrix was fortified with PCB congeners and extracted by an automated solid phase extraction system using C18 sorbent. The extracts were analyzed at two ion source temperatures, 230 and 300 degrees C. The use of high ion source temperature increased the abundances of high-mass ions, and the response factors in SIM mode for PCBs. An excellent linearity from 0.5 to 100 ng/ml at ion source temperature of 300 degrees C was demonstrated, with a calculated detection limit of 0.1 ng/g serum. Seven replicate fortifications of newborn calf serum, at three spiking levels of 1, 10, and 50 ng/g of serum, gave mean recoveries of 110%, 85%, and 98%, with average relative standard deviation (RSD) values of 5.4%, 7.3%, and 4.7%, respectively.


Asunto(s)
Bifenilos Policlorados/sangre , Calibración , Cromatografía de Gases y Espectrometría de Masas , Humanos , Indicadores y Reactivos , Control de Calidad , Estándares de Referencia , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Temperatura
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