Total and conjugated urinary paranitrophenol after an acute parathion ingestion

Oneto, M. L.; Basack, Silvana; Kesten, Eva

doi:10.1016/s1355-0306(95)72663-6

Cited by 9 publications

(5 citation statements)

References 9 publications

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“…In the case of TCPY, no traces of the free form could be detected without hydrolysis, whereas traces of unbound PNP could be found in a large portion of the samples. From 45% to 99% of the total PNP was conjugated in this study, and that is in accordance with results reported by Oneto et al [22] where 81% of the total PNP was sulfate conjugated. The difference in the amounts of free metabolite between TCPY and PNP could result from the lower LOD for PNP, which might make it possible to detect low levels of free PNP, or by different metabolic rates of the two compounds.…”

Section: Discussionsupporting

confidence: 93%

“…4), the hydrolysis step is critical for accurate quantification of PNP and TCPY. Earlier studies also have shown the importance of including a hydrolysis step in the analysis of phenolic metabolites [4,22]. In the case of TCPY, no traces of the free form could be detected without hydrolysis, whereas traces of unbound PNP could be found in a large portion of the samples.…”

Section: Discussionmentioning

confidence: 97%

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A liquid chromatography/electrospray ionization?tandem mass spectrometry method for quantification of specific organophosphorus pesticide biomarkers in human urine

Olsson

Nguyen

Sadowski

et al. 2003

Analytical and Bioanalytical Chemistry

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Organophosphorus pesticides are commonly used in both agricultural and residential settings. The widespread use of these chemicals makes it almost impossible for humans to avoid exposure. In order to determine background human exposure, there is a need for fast, reliable, and sensitive analytical methods. We have developed a sensitive method to quantify specific biomarkers of the organophosphorus pesticides acephate, azinphos, chlorpyrifos, coumaphos, diazinon, isazofos, malathion, methamidophos, parathion and pirimiphos or their O,O-dimethyl analogues in human urine, as their selective metabolites or as the intact pesticide. Isotopically labeled internal standards were used for eight of the analytes. The use of labeled internal standards in combination with high-performance liquid chromatography electrospray ionization-tandem mass spectrometry provided a high degree of specificity. Repeated analysis of urine samples fortified with high and low concentrations of the analytes gave relative standard deviations (RSD) of less than 10% for the analytes with an isotopically labeled standard. Analytes without isotopically labeled standards had higher RSD. For all compounds except methamidophos and acephate, the recoveries were greater than 70%. The limits of quantification for most of the analytes were in the range of 0.1 to 1 ng/mL. We detected concentrations of most of these pesticides and/or their metabolites in urine samples from non-occupationally exposed persons using our method. Our frequencies of detection for the analytes measured ranged from 1% to 98%.

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Section: Discussionsupporting

confidence: 93%

Section: Discussionmentioning

confidence: 97%

A liquid chromatography/electrospray ionization?tandem mass spectrometry method for quantification of specific organophosphorus pesticide biomarkers in human urine

Olsson

Nguyen

Sadowski

et al. 2003

Analytical and Bioanalytical Chemistry

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show abstract

“…The markers are specific hydrolysis products of chlorpyriphos, coumaphos, diazinon, isazophos, malathion, parathion, and pirimiphos or their methyl counterparts. Most of these markers have been detected in human or animal urine, ,− but to our knowledge, the specific hydrolysis product of isazophos has never been confirmed in urine. We measured five metabolites to evaluate exposure to the synthetic pyrethroids.…”

mentioning

confidence: 90%

A Liquid Chromatography−Tandem Mass Spectrometry Multiresidue Method for Quantification of Specific Metabolites of Organophosphorus Pesticides, Synthetic Pyrethroids, Selected Herbicides, and DEET in Human Urine

et al. 2004

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The ability to estimate low-dose human exposure to commonly used pesticides often is requested in epidemiologic studies. Therefore, fast and robust methods are necessary that can measure many analytes in the same sample. We have developed a method for high-throughput analysis of 19 markers of commonly used pesticides in human urine. The analytes were seven specific metabolites of organophosphorus pesticides, five metabolites of synthetic pyrethroids, six herbicides or their metabolites, and one insect repellant. Human urine (2 mL) was spiked with stable isotopically labeled analogues of the analytes, enzymatically hydrolyzed, extracted using solid-phase extraction, concentrated, and analyzed using high-performance liquid chromatography-tandem mass spectrometry. The sample was divided into two portions and analyzed on two different mass spectrometers, one using atmospheric pressure chemical ionization (APCI) and the other using turbo ion spray atmospheric pressure ionization (TIS). All analytes except the pyrethroid metabolites were analyzed using APCI. The detection limits for all analytes ranged from 0.1 to 1.5 ng/mL of urine, with the majority (17) below 0.5 ng/mL. The analytical precision for the different analytes, estimated as both the within-day and between-day variation, was 3-14 and 4-19%, respectively. The extraction recoveries of the analytes ranged from 68 to 114%. The throughput, including calibration standards and quality control samples, is approximately 50 samples a day. However, the analysis time with the TIS application is much shorter, and if only pyrethroid metabolite data are of interest, the throughput can be increased to 100-150 samples/day.

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“…The tubes were sealed and placed in a boiling water bath for 1 hr. This procedure is analogous to the one recommended by Renner and Hopfer (1990), and it was optimized in our laboratory for p-nitrophenol (Oneto et al , 1995). Once they were cool, the hydrolyzed solutions were treated with K2C03 until pH 10 was reached, and then acetylated by the procedure described previously.…”

Section: Methodsmentioning

confidence: 99%

Accumulation and Elimination of Pentachlorophenol in the Freshwater Bivalve Corbicula fluminea

Basack

Oneto

Guerrero

et al. 1997

Bulletin of Environmental Contamination and Toxicology

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Total and conjugated urinary paranitrophenol after an acute parathion ingestion

Cited by 9 publications

References 9 publications

A liquid chromatography/electrospray ionization?tandem mass spectrometry method for quantification of specific organophosphorus pesticide biomarkers in human urine

A liquid chromatography/electrospray ionization?tandem mass spectrometry method for quantification of specific organophosphorus pesticide biomarkers in human urine

A Liquid Chromatography−Tandem Mass Spectrometry Multiresidue Method for Quantification of Specific Metabolites of Organophosphorus Pesticides, Synthetic Pyrethroids, Selected Herbicides, and DEET in Human Urine

Accumulation and Elimination of Pentachlorophenol in the Freshwater Bivalve Corbicula fluminea

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