Kim, M; Song, NR; Choi, JH; Lee, J; Pyo, H
Phthalates are used in industry products, household items, and medical tools as plasticizers. Human exposure to phthalates has raised concern about its toxicity. In the present study, optimization was conducted for the simultaneous analysis of eight kinds of phthalate metabolites using gas chromatography-mass spectrometry (GC-MS): MEP, MiBP, MnBP, MBzP, MiNP, MEHP, MEOHP, and MEHHP. In order to minimize the matrix effect and to do quantitative analysis, isotope dilution and LLE-GC-MS methods were performed. Urine samples were enzymatically hydrolyzed, extracted with a mixture of n-hexane and ethyl ether (8:2; v:v), and subsequently derivatized with trimethylsilylation. All eight kinds of analytes showed clear resolution and high reproducibility in GC-MS results. The method detection limit ranged from 0.05ng/mL to 0.2ng/mL. Calibration curves were found to be linear from 0.2 to 100ng/mL with -(2)>0.992. The relative standard deviation of the intraday precision using water and urine ranged from 2.1% to 16.3%. The analysis was performed with urine samples that were collected from adults residing in the Republic of Korea. The analyzed concentration results were compared according to gender and region. As a result, DEHP metabolites showed the highest detected concentration (75.92μg/g creatinine, 100%), and MiNP, a metabolite of DiNP, showed the lowest detected concentration (0.42μg/g creatinine, 22.5%). On average, female urine (200.76μg/g creatinine) had a higher detected concentration of ∑8 phthalate metabolites than male urine. Samples from rural regions (211.96μg/g creatinine) had higher levels than samples from urban regions.
Biomonitoring; Gas chromatography-mass spectrometry; Isotope dilution; Trimethylsilylation; Urinary phthalate metabolites; Biomolecules; Body fluids; Chemical analysis; Functional polymers; Gas chromatography; Isotopes; Metabolites; Potassium compounds; Solvents; Isotope dilutions; Phthalate metabolites; Trimethyl silylation; mono n butylphthalate; mono(2 ethyl 5 hydroxyhexyl)phthalate; mono(2 ethyl 5 oxohexyl)phthalate; monobenzylphthalate; monoethylhexylphthalate; monoethylphthalate; monoisobutylphthalate; monoisononylphthalate; phthalic acid derivative; unclassified drug; concentration (composition); mass spectrometry; metabolite; phthalate; article; controlled study; hydrolysis; isotope dilution assay; limit of detection; mass fragmentography; priority journal; process optimization; quantitative analysis; reproducibility; sex difference; silylation; South Korea; urban rural difference; urinalysis; Environmental Exposure; Environmental Pollutants; Phthalic Acids; Plasticizers; Republic of Korea