Study on determination of PAEs in water samples by using solid phase extraction combined with gas chromatography-mass spectrometry

Abstract

       Phthalic acid diesters (PAEs) are industrial chemicals used as plasticizers in a variety of commercial products. Due to wide usage, PAEs have been found in various environments and their human exposure risks have also attracted a lot of concerns. However, little information about the distributions of PAEs in the water samples collected from Vietnam was reported. In this study, the method for the determination of nine typical PAEs in water samples by using the solid phase extraction (SPE) combined with gas chromatography-mass spectrometry (GC-MS) technique was optimized. The method detection limits (MDLs) and method quantitation limits (MQLs) of PAEs in water samples were in ranges of 0.2–0.4 ng/L and (0.6-1.2) ng/L, respectively. The recoveries of surrogate compounds in blank and real samples ranged from (74.8 to 93.9) %, with RSD < 9.2 %. The calibration curve for all standards was linear over a concentration range of (1.0-1,000) ng/mL (with R² ≥ 0.998). The total concentrations of PAEs measured in bottled water of six brands were ranged from 10.0 ng/L to 6,690 ng/L. Among the studied PAEs, di-(2-ethylhexyl) phthalate (DEHP) was found at the highest frequencies and concentrations. Overall, the distribution of PAEs in plastic bottled water is significantly lower than the permitted regulations (only with DEHP) in drinking water by the Ministry of Health of Vietnam in 2011.