Objective: A method for the determination of 5 kinds of phthalate monoesters in urine by solid-phase extraction and gas chromatography-mass spectrometry was developed.
Methods: After urine enzymatic hydrolysis by β-glucuronidase, the sample was pretreated by SPE. Phthalate monoesters were eluted by boron trifluoridemethanol complex, and determined by gas chromatograph-mass spectrometer with DB-5 ms Phenomenex( 30 m × 0. 25 mm, 0. 25 μm).
Results: Within the concentration range of25. 0-1000 μg/L, the relationship between peak area and concentration of 5 kinds of phthalate monoesters presented linear relation. The correlation coefficient was 0. 9989-0. 9996, and the determination limit was 10. 0-15. 0 μg/L. The recoveries of phthalate monoesters were in the range of 80. 2%-97. 8% when set at 15. 0, 200 and 500 μg/L concentration levels, and the relative standard deviation was in the range of 4. 2%-10. 2%( n = 6). A total of 81 pregnant women were detected by this method and thedetection rate was 98. 7%.
Conclusion: This method could be used in the simultaneous determination of 5 kinds of phthalate monoesters.
Keywords: gas chromatography-mass spectrometry; phthalate ester metabolites; urine.