The determination of N-nitrosodimethyl-amine (NDMA) in beer by matrix dispersion solid phase extraction and GC-TEA detection
De bepaling van N-nitrosodimethylamine (NDMA) in bier via extractie met vaste stof matrix dispersie en GC-TEA meting
Koole A , Vaessen HAMG
RIVM Report 389103001
The determination of N-nitrosodimethylamine (NDMA) is beer by matrix dispersion solid phase extraction on Celite and GC-TEA detection was studied. The procedure that came out is described in the Annex and was labeled with performance characteristics resulting from the analysis of 11 beer samples differing in matrix composition as widely as possible. All samples were assayed, at least, in duplicate. NDMA levels found ranged, on average from 0.09 to 0.26 mug/kg. Sample 93M0198 contained on average (N=6) 0.13 mug/kg of NDMA and the coefficient of variation was 9.5%. For the remaining samples the repeatability, calculated as the difference in procent of the individual result versus the average result of the sample, is 15% or better. In all, 15 recovery experiments were carried out at NDMA spiking levels of 0.2 - 0.5 and 1.0 mug/kg. On average the recovery was 100 +/- 6%. The limit of detection and of quantitation were calculated from the results of 4 blank determinations, resulting in a tentative value of about 0.05 mug/kg and of about 0.1 mug/kg respectively. The determination of NDMA in beer by matrix dispersion solid phase extraction and GC-TEA detection is easy to handle and much faster, but less sensitive, then the combination of vacuum distillation and GC-TEA detection used so far.