Dispersive micro-solid phase extraction combined with gas chromatography-chemical ionization mass spectrometry for the determination of N-nitrosamines in swimming pool water samples.
A simple sample pretreatment technique, dispersive micro-solid phase extraction, was applied for the extraction of N-nitrosodimethylamine (NDMA) and other four N-nitrosamines (NAs) from samples of swimming pool water. The parameters affecting the extraction efficiency were systematically investigated. The best extraction conditions involved immersing 75 mg of carbon molecular sieve, Carboxen™ 1003 (as an adsorbent), in a 50-mL water sample (pH 7.0) containing 5% sodium chloride in a sample tube. After 20 min of extraction by vigorous shaking, the adsorbent was collected on a filter and the NAs desorbed by treatment with 150 μL of dichloromethane. A 10-μL aliquot was then directly determined by large-volume injection gas chromatography with chemical ionization mass spectrometry using the selected ion storage mode. The limits of quantitation were <0.9 ng/L. The precision for these analytes, as indicated by relative standard deviations, were <8% for both intra- and inter-day analyses. Accuracy, expressed as the mean extraction recovery, was between 62% and 109%. A preliminary analysis of swimming pool water samples revealed that NDMA was present in the highest concentration, in the range from n.d. to 100 ng/L.
Department of Chemistry, National Central University, Chung-Li, Taiwan.
Ssu-Chieh
SC
Fu
Shin-Hwa
SH
Tzing
Hsin-Chang
HC
Chen
Yu-Chen
YC
Wang
Wang-Hsien
WH
Ding
D004128:Dimethylnitrosamine / Q000032:analysis / Q000302:isolation & purification; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D057230:Limit of Detection; D009602:Nitrosamines / Q000032:analysis / Q000302:isolation & purification*; D052616:Solid Phase Extraction / Q000379:methods*; D013551:Swimming Pools; D014867:Water / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000302:isolation & purification*
D009602:Nitrosamines; D014874:Water Pollutants, Chemical; D014867:Water; D004128:Dimethylnitrosamine