Gas chromatography-mass spectrometry (GC-MS) with a 100 m capillary column at different oven temperatures is employed to separate isothermally p-nonylphenol into 21 isomers. Analysis of the resulting mass spectra of these isomers indicates that they could be classified into six groups with respect to different configurations of the alpha- and beta-C-atoms on the alkyl chains. Based on these basic structures nonylphenol isomers are synthesized and also characterized by GC-MS. The obtained data elucidate the complete structures of 10 nonylphenol isomers of the technical mixture. The most important features of the mass spectra and the 1H and 13C nuclear magnetic resonance (NMR) spectra of these isomers are presented.
In recent years, the number of waterpipe smokers has increased substantially worldwide. Here, we present a study on the identification and quantification of seven carbonylic compounds including formaldehyde, acetaldehyde and acrolein in the mainstream smoke of the waterpipe. Smoking was conducted with a smoking machine, and carbonyls were scavenged from the smoke with two impingers containing an acidic solution of 2,4-dinitrophenylhydrazine. The derivatives were then analyzed by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). For instance, during one waterpipe smoking session, up to 111 ± 12 μg formaldehyde could be detected. This value is about 5 times higher when compared to one 2R4F reference cigarette. We also found a distinct filter effect of the bowl water for all carbonyls investigated. Our data further demonstrate that increasing amounts of humectants in the unburned tobacco lowers the temperature in the waterpipe head during smoking, thereby resulting in decreasing levels of carbonyls in the smoke produced. Altogether, considerable amounts of toxic carbonyls are present in the waterpipe smoke, thus conferring a health risk to waterpipe smokers.
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