Analysis of nitrosamines in water by automated SPE and isotope dilution GC/HRMS Occurrence in the different steps of a drinking water treatment plant, and in chlorinated samples from a reservoir and a sewage treatment plant effluent.
A method based on automated solid-phase extraction (SPE) and isotope dilution gas chromatography/high resolution mass spectrometry (GC/HRMS) has been developed for the analysis of nine nitrosamines in water samples. The combination of automated SPE and GC/HRMS for the analysis of nitrosamines has not been reported previously. The method shows as advantages the selectivity and sensitivity of GC/HRMS analysis and the high efficiency of automated SPE with coconut charcoal EPA 521 cartridges. Low method detection limits (MDLs) were achieved, along with a greater facility of the procedure and less dependence on the operator with regard to the methods based on manual SPE. Quality requirements for isotope dilution-based methods were accomplished for most analysed nitrosamines, regarding to trueness (80-120%), method precision (<15%) and MDLs (0.08-1.7 ng/L). Nineteen water samples (16 samples from a drinking water treatment plant {DWTP}, 2 chlorinated samples from a sewage treatment plant {STP} effluent, and 1 chlorinated sample from a reservoir) were analysed. Concentrations of nitrosamines in the STP effluent were 309.4 and 730.2 ng/L, being higher when higher doses of chlorine were applied. N-Nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) were the main compounds identified in the STP effluent, and NDEA was detected above 200 ng/L, regulatory level for NDMA in effluents stated in Ontario (Canada). Lower concentrations of nitrosamines were found in the reservoir (20.3 ng/L) and in the DWTP samples (n.d. -28.6 ng/L). NDMA and NDEA were respectively found in the reservoir and in treated and highly chlorinated DWTP samples at concentrations above 10 ng/L (guide value established in different countries). The highest concentrations of nitrosamines were found after chlorination and ozonation processes (ozonated, treated and highly chlorinated water) in DWTP samples.
Planas
Carles
C
Mass Spectrometry Laboratory, Department of Ecotechnologies, IIQAB, CSIC, Jordi Girona Salgado 18, 08034 Barcelona, Spain.
Palacios
Oscar
O
Ventura
Francesc
F
Rivera
Josep
J
Caixach
Josep
J
D001331:Automation; D002713:Chlorine / Q000032:analysis; D002849:Chromatography, Gas / Q000295:instrumentation / Q000379:methods*; D004052:Diethylnitrosamine / Q000032:analysis; D004128:Dimethylnitrosamine / Q000032:analysis; D007700:Kinetics; D009602:Nitrosamines / Q000032:analysis*; D010126:Ozone / Q000032:analysis; D011786:Quality Control; D012722:Sewage / Q000032:analysis; D052616:Solid Phase Extraction / Q000379:methods; D013997:Time Factors; D014867:Water / Q000032:analysis; D018508:Water Purification / Q000379:methods*; D014881:Water Supply / Q000032:analysis*
D009602:Nitrosamines; D012722:Sewage; D014867:Water; D004052:Diethylnitrosamine; D002713:Chlorine; D010126:Ozone; D004128:Dimethylnitrosamine