Determination of Dechloranes in waste water by GC-NCI/MS

A method for the determination of Dechlorane 602(Dec 602), Dechlorane 603(Dec 603), Dechlorane 604(Dec 604) and Dechlorane Plus(DP) in wastewater by gas chromatography-negative ion chemical ionization mass spectrometry(GC-NCI/MS) has been developed. The water sample was extracted by classical liquid-liquid extraction method to collect the Dechloranes from both particle phase and water phase, cleaned up using silica gel and then analyzed by GC-NCI/MS under the optimized conditions of 150°C source temperature, 150°C quadrupole temperature, 280°C initial temperature and 1kV electron multiplier(EM) offset voltage. The quantitation limits of Dec 602, Dec 603, Dec 604 and DP were 0.01-0.1 ng · L^-1. The correlation coefficients were above 0.99 for the calibration curves. The validity of this method was demonstrated by determination of Dechloranes in wastewater of a municipal wastewater treatment plant in Harbin, China. The results indicate that the recovery rates of all Dechloranes in wastewater are 74%-122%, the relative standard deviations(D_RS) are less than 13.2%. The concentrations of Dechloranes in influent and effluent are 3.2 ng · L^-1 and 0.19 ng · L^-1, respectively. Dechloranes are dominanted by DP in wastewater.