Quantitative Detection of Eight Phthalate Metabolites in Human Urine Using HPLC−APCI-MS/MS

Blount, Benjamin C.; Milgram, K. Eric; Silva, M J; Malek, Nicole A.; Reidy, John A.; Needham, Larry L.; Brock, John W.

doi:10.1021/ac000422r

Cited by 330 publications

(228 citation statements)

References 24 publications

(35 reference statements)

Supporting

Mentioning

219

Contrasting

Unclassified

Order By: Relevance

“…All methods except the dialkylphosphate (DAP) metabolites of organophosphate insecticides employ a b-glucuronidase enzyme digestion to liberate the analytes of interest from their glucuronide or sulfate conjugates, though the spiked urine sample was enriched with the nonconjugated species. Specifically, phthalates were measured using the method of Blount et al (2000) as modified by Silva et al (2003), using solid phase extraction (SPE) and analysis using isotope dilution high-performance liquid chromatographyatmospheric pressure chemical ionization-tandem mass spectrometry (HPLC-APCI-MS/MS). BPA was measured using the method by Kuklenyik et al (2003); during the automated SPE, BPA was simultaneously extracted from the urine and converted to its pentafluorobenzyl ether on commercial styrene-divinylbenzene copolymer-based SPE cartridges.…”

Section: Methodsmentioning

confidence: 99%

Impact of urine preservation methods and duration of storage on measured levels of environmental contaminants

Hoppin

Ulmer

Calafat

et al. 2005

J Expo Sci Environ Epidemiol

View full text Add to dashboard Cite

Collection of urine samples in human studies involves choices regarding shipping, sample preservation, and storage that may ultimately influence future analysis. As more studies collect and archive urine samples to evaluate environmental exposures in the future, we were interested in assessing the impact of urine preservative, storage temperature, and time since collection on nonpersistent contaminants in urine samples. In spiked urine samples stored in three types of urine vacutainers (no preservative, boric acid, and chlorhexidine), we measured five groups of contaminants to assess the levels of these analytes at five time points (0, 24, 48, and 72 h, and 1 week) and at two temperatures (room temperature and 41C). The target chemicals were bisphenol A (BPA), metabolites of organophosphate (OP), carbamate, and pyrethroid insecticides, chlorinated phenols, and phthalate monoesters, and were measured using five different mass spectrometry-based methods. Three samples were analyzed at each time point, with the exception of BPA. Repeated measures analysis of variance was used to evaluate effects of storage time, temperature, and preservative. Stability was summarized with percent change in mean concentration from time 0. In general, most analytes were stable under all conditions with changes in mean concentration over time, temperature, and preservative being generally less than 20%, with the exception of the OP metabolites in the presence of boric acid. The effect of storage temperature was less important than time since collection. The precision of the laboratory measurements was high allowing us to observe small differences, which may not be important when categorizing individuals into broader exposure groups.

show abstract

Section: Methodsmentioning

confidence: 99%

Impact of urine preservation methods and duration of storage on measured levels of environmental contaminants

Hoppin

Ulmer

Calafat

et al. 2005

J Expo Sci Environ Epidemiol

View full text Add to dashboard Cite

show abstract

“…The method used has been described previously (23). All samples were spiked with 13 C 4 -labeled phthalate monoesters and 4-methylumbelliferone glucuronide.…”

Section: Methodsmentioning

confidence: 99%

“…We report the urinary phthalate monoester levels for a human reference population using a new, highly selective technique (23). This analytical approach allows us to directly measure the individual phthalate metabolites responsible for the reproductive and developmental toxicity of phthalates in animals while avoiding contamination from the ubiquitous parent compound.…”

mentioning

confidence: 99%

Levels of Seven Urinary Phthalate Metabolites in a Human Reference Population

Blount¹,

Silva²,

Caudill³

et al. 2000

Environmental Health Perspectives

Self Cite

117

147

View full text Add to dashboard Cite

Dialkyl or alkyl aryl esters of 1,2-benzenedicarboxylic acid, commonly called phthalates, are ubiquitous industrial chemicals with a wide range of chemical and toxicologic characteristics. Phthalates are used primarily as plasticizers in flexible polyvinyl chloride (PVC) products such as blood bags and children's toys. Nonpolymeric uses of phthalates as fixatives, detergents, lubricating oils, and solvents lead to their inclusion in numerous and diverse products such as cosmetics and wood finishes. The widespread use of phthalates results in multiple human exposure routes (oral, dermal, inhalation, and intravenous). Phthalates are lipophilic compounds that appear not to bioaccumulate (1). Phthalates are rapidly metabolized to their respective monoesters and further oxidative products, which are glucuronidated and excreted through the urine and feces (1-4).Animal toxicology of several phthalates has been studied. Di-(2-ethylhexyl) phthalate (DEHP) is a rodent liver carcinogen through a mechanism thought to involve peroxisome proliferation (5); however, carcinogenicity by this mechanism is unlikely to be relevant to humans (6,7). Several phthalates, DEHP, dibutyl phthalate (DBP), and benzyl butyl phthalate (BzBP), are teratogenic in animals (8-10). DBP is also toxic to the testes, possibly through its metabolite, monobutyl phthalate (MBP) (11,12); other phthalate metabolites, monobenzyl phthalate (MBzP) and mono-2-ethylhexyl phthalate (MEHP), are Sertoli cell toxicants and teratogens in animals (13,14). Furthermore, administration of DBP and DEHP to pregnant rats interferes with normal fetal development in male offspring (15). Regarding reproductive and developmental effects, phthalates vary in potency, with DEHP being the most potent and DBP and BzBP roughly an order of magnitude less potent (8)(9)(10)(11)(12)(13)(14)(15).Based on the varied toxicities of phthalates, internal dose measurements of specific phthalates and their monoester metabolites (16) are important for exposure assessment, and ultimately for accurate human risk assessment. Previous methods for assessing human exposure to phthalates have been subject to laboratory and sample-collection contamination problems from these environmentally ubiquitous compounds (17)(18)(19)(20). For this reason, previous measurements of internal phthalate dose have focused on highly exposed people (21,22). As the primary urinary metabolite, phthalate monoesters are useful biomarkers of specific phthalate exposure.We report the urinary phthalate monoester levels for a human reference population using a new, highly selective technique (23). This analytical approach allows us to directly measure the individual phthalate metabolites responsible for the reproductive and developmental toxicity of phthalates in animals while avoiding contamination from the ubiquitous parent compound. The metabolites measured are monoethyl phthalate (MEP), MBP, MBzP, mono-n-octyl phthalate, MEHP, and mono-3-methyl-5-dimethylhexyl phthalate (monoisononyl, MINP). Commercially used di-isononyl p...

show abstract

“…To samples requiring deglucuronidation, -glucuronidase (E. coli, 5 l, 200 U / ml, Roche Biochemical, Mannheim, Germany ) was added followed by incubation at 378C for 90 min. This treatment is sufficient to deconjugate the glucuronides of both 5-methylumbelliferone and phthalate monoesters ( Blount et al, 2000 ). After enzymatic treatment, 1 ml of formic acid (32%; EM Industries, Gibbsville, NJ ) was added to the sample and then buffered with ammonium acetate (250 l, 1 M, pH 6.5, Sigma, Milwaukee, WI ) .…”

Section: Methodsmentioning

confidence: 99%

Measurement of bisphenol A levels in human urine

Brock

Yoshimura

Barr

et al. 2001

J Expo Sci Environ Epidemiol

View full text Add to dashboard Cite

We report a new approach for assessing human exposure to bisphenol A ( BPA ) by measuring BPA in urine after enzymatic deglucuronidation. This method involves addition of 13 C 12 -labeled BPA, enzymatic deconjugation, solid -phase extraction, and derivatization with pentafluorobenzyl bromide. The product of the derivatization is separated by gas chromatography followed by mass spectrometric detection using negative chemical ionization and selected ion monitoring. Using this analysis method, urine samples fortified with both a constant level of labeled BPA and a range of unlabeled BPA levels ( 0.27 -10.6 ng / ml ) demonstrated constant percentage recovery. In addition, a range of urine sample volumes ( 0.25 -10.0 ml ) with constant amounts of added internal standard produced a linear response ( r 2 = 0.99 ) . The method limit of detection was 0.12 ng / ml. This method was validated by duplicate analyses using gas chromatography coupled to a high -resolution mass spectrometer.

show abstract

Quantitative Detection of Eight Phthalate Metabolites in Human Urine Using HPLC−APCI-MS/MS

Cited by 330 publications

References 24 publications

Impact of urine preservation methods and duration of storage on measured levels of environmental contaminants

Impact of urine preservation methods and duration of storage on measured levels of environmental contaminants

Levels of Seven Urinary Phthalate Metabolites in a Human Reference Population

Measurement of bisphenol A levels in human urine

Contact Info

Product

Resources

About