CONTAMINATION OF BEER BY N-NITROSODIMETHYLAMINE

A small survey of 27 beers (24 domestic beers and 3 imported beers) was conducted in view to assess contamination with N-nitrosamines, particularly with N-nitrosodimethylamine (NDMA). Extractions of these contaminants were carried out using CHEM ELUT cartridges. Elution was made with dichloromethane. The extracts were analysed directly by gas chromatography coupled to a chemiluminescence detector: the Thermal Energy Analyzer detector (TEA). NDMA was found regularly in 24 samples at levels ranging from not detected to 1.5 mu-g/l. The mean contamination for overall beer samples checked was 0.23 mu-g/l. The average daily intake was estimated as 0.03 mu-g NDMA for French people. The use of technological modifications during the malt kilning is considered as responsible for the low levels of NDMA found, compared with those obtained in the past (in 1979).