DETERMINATION OF ACRYLAMIDE MONOMER IN HYDROPONICALLY GROWN TOMATO FRUITS BY CAPILLARY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

Tomato (Lycopersicon esculentum L) fruits from plants grown hydroponically on polyacrylamide gel were obtained in order to assess any possible uptake of acrylamide monomer from the nutrient solution to the fruit during cultivation. Analysis of acrylamide in the gel itself involved aqueous extraction, bromination and then capillary GC determination with nitrogen-specific detection. By standard addition a level of 0.18 +/- 0.01 g kg-1 residual monomer was found to be present in a sample of gel used by an experimental horticultural station. Tomato fruits were analysed by extraction of the aqueous phase, bromination, silica-gel cartridge clean-up and capillary GC-MS determination by selected ion monitoring. The recovery of the method was 26-62% but losses throughout were compensated for by use of 2,3-dibromo-2-dimethylpropionamide internal standard. No acrylamide monomer could be detected in tomato fruits from plants grown hydroponically on polyacrylamide gel at a limit of detection of 1 x 10(-6) g kg-1, demonstrating that the monomer is not transferred from the growing medium into tomato fruits.