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.
Bibliographical noteFunding Information:
This research was supported by a grant ( 10162KFDA994 ) from the Korea Food & Drug Administration in 2010, and a grant from the Eco Innovation Technology Development Program of the Ministry of Environment, and the Intramural Research Program at the Korea Institute of Science and Technology.
- Gas chromatography-mass spectrometry
- Isotope dilution
- Urinary phthalate metabolites
ASJC Scopus subject areas
- Environmental Engineering
- Environmental Chemistry
- Waste Management and Disposal