Determination of Migration Levels of N-Nitrosamines and N-Nitrosatable Substances from Balloons by Gas Chromatography-Positive Chemical Ionization Mass Spectrometry

For analysis of a bunch of samples,a rapid,selective,sensitive and precision method in EN 12868:1999 was developed to determine the release of N-nitrosamines and N-nitrosatable substances from elastomer or rubber teats and soothers in both of sample preparation and instrumental analysis.To imitate the migration of N-nitrosamines and N-nitrosatable substances from rubber balloons and teats to human body,rubber products studied in this research were soaked in artificial saliva.The target analytes released to artificial saliva were extracted by Sep-Pak AC2 connected to Sep-Pak Dry cartridges,and isolated by DB 624 GC column,and determined by positive chemical ionization mass spectrometry in both full scan and SIM mode.Linear concentration-response relationships were obtained in a calibration range from 10 to 1000 μg/L with high correlation(R0.99) for all target analytes.The method detection limits of each N-nitrosamines and N-nitrosatable substances released from rubber products were 1.25 and 5.00 μg/kg,respectively,which are much lower than the requirement of Directive 93/11/EEC(N-nitrosamines: 10 μg/kg;N-nitrosatable substances: 100 μg/kg).The average spike recoveries ranged from 80.6% to 95.5%(RSD 4.2%-7.7%,n =6),from 86.8% to 98.3%(RSD 4.1%-5.8%,n=6),and from 92.2% to 110.4%(RSD 2.6%-4.3%,n=6) for the spiked levels of 1.25,12.5 and 125 μg/kg,respectively.The total concentrations of seven N-nitrosamines and N-nitrosatable substances in analyzed balloon samples ranged from 0.421 mg/kg to 0.820 mg/kg and from 3.616 mg/kg to 8.437 mg/kg,respectively,which did not comply with the requirement of Directive 93/11/EEC.However,all N-nitrosamines and N-nitrosa-table substances were not detected in analyzed teats and soothers samples.