Determination of Bisphenol A and Degraded Compounds of Alkylphenol Ethoxylates in Water by Gas Chromatograph-Mass Spectrometry

Objectives A method for the determination of Bisphenol A and degraded compounds of alkylphenol ethoxylates (NP, OP, NP1EO, NP2EO, OP1EO and OP2EO) in water was developed by using GC-MS.

Methods After acidification with concentrated hydrochloric acid and addition of 4-nonlphenol and 4-nonylphenol monoethoxylate as internal standards, the water sample was subsequently extracted with dichloromethane. After concentrated, the target analytes were converted to their derivatives by using BSTFA and then were performed chromatographic separation and detection with GC-MS.

Results Good dynamic linearities were obtained in the range of investigated concentration (10~200 μg/L) with R²≥0.9992. The method detection limits (MDLs) were in the range of 1.39~5.34 ng/L. The interday (n=5) and intraday (n=5) recoveries at two spiking concentrations (20 and 100 ng/L) were in the range of 85%~105%, and the RSDs were less than 6.5% for all target analytes. The monitoring of drinking water samples collected from Shanghai Municipality showed a detected rate of 100% and an exposure concentration in the range of 0.5~90 ng/L for various analytes.

Conclusions The method has been proved to be rapid, robust and feasible for the requirement of analysing trace amount of these compounds in water with low cost and less labor and time consumption.