Simultaneous Determination of Di(2‐ethylhexyl)phthalate, Mono(2‐ethylhexyl)phthalate, and Phthalic Acid Migrating from Gamma‐Ray Irradiated Polyvinyl Chloride Sheet by Liquid Chromatography‐Tandem Mass Spectrometry

Abstract

The aim of the present study was to establish a liquid chromatography‐tandem mass spectrometric (LC‐MS/MS) method for the simultaneous determination of di(2‐ethylhexyl) phthalate (DEHP), mono(2‐ethylhexyl)phthalate (MEHP), and phthalic acid (PA). In the proposed method, the limits of detection of DEHP, MEHP, and PA were 5, 0.5, and 1 ng/mL, respectively, and the limits of quantification with standard solutions were 20, 2, and 5 ng/mL, respectively. Intra‐ and interday assays showed good accuracy and repeatability. The recoveries of DEHP, MEHP, and PA from respective extraction solvents ranged from 98.9 to 104.2% (relative standard deviation was below 10.3%). DEHP and its breakdown products migrating from gamma‐ray irradiated polyvinyl chloride (PVC) sheets were determined simultaneously since DEHP is easily eluted from PVC medical devices. DEHP migration was noted from both gamma‐ray irradiated and control PVC sheets. Compared with the migration from the control PVC sheet, MEHP showed significant migration from the gamma‐ray irradiated PVC sheet. In contrast, PA migration was noted only from the gamma‐ray irradiated PVC sheet.