Selected primary aromatic amines (PAAs) in e-cigarette vapor by GC-MS
Primary aromatic amines (PAAs) are compounds of interest to a number of tobacco regulators and are routinely found in mainstream (MS) tobacco smoke. Six of the 93 compounds currently included on the United States Food and Drug Administration (FDA) established list of harmful and potentially harmful constituents (HPHCs) in tobacco products and tobacco smoke (HPHCs) are primary aromatic amines. Health Canada and ANVISA Brazil also require the reporting of PAAs. With the increasing interest in e-cigarette and other vapor products, there is need for sensitive methods of measurement for PAAs, which are expected to occur at much lower levels in these types of products. The method described here is a modification of a method used routinely in a high-sample throughput laboratory for PAA analysis in MS smoke and demonstrates the successful analysis of four PAAs in e-cigarette vapor: 1- and 2- aminonaphthalene and 3- and 4-aminobiphenyl.
E-cigarette vapor is collected using a 44-mm Cambridge filter pad (CFP). Once the vapor collection is complete the CFP is extracted with methylene chloride for 30 minutes using mechanical shaking. A portion of the extract is evaporated to approximately 2.5 mL, dried with sodium sulfate and derivatized with pentafluoropropionic acid anhydride (PFPA). The final sample is analyzed by GC-MS using negative chemical ionization.
The calibration range for the aminonapthalenes is 10 pg/mL to 500 pg/mL and the range for the aminobiphenyls is 5 pg/mL to 250 pg/mL. It should be noted that, even with a lower limit of quantitation (LLOQ) of 50 pg/pad, no quantifiable PAAs have been observed in the vapor from any e-cigarettes tested to date.