光电离质谱法测定卷烟烟气中有害成分的口腔残留

Determination of buccal residues of harmful components from cigarette smoke by photoionization mass spectrometry

为了在线研究卷烟烟气中有害化学成分在人体口腔中的残留,建立了一种基于真空紫外光电离飞行时间质谱的测量装置,获得了新鲜卷烟主流烟气气相物及其在人体口腔中停留不同时间后的光电离质谱图,并根据定性分析结果,对质荷比（m/z）30、44、54、58、68、78、94和106所对应的主要烟气有害化学成分（一氧化氮、乙醛、1,3-丁二烯、丙酮、异戊二烯、苯、苯酚和乙苯）在口腔中的残留效率进行了对比分析。结果表明：（1）当卷烟烟气在口腔中停留2 s时,醛酮类化合物具有较高的口腔残留效率,其次为苯酚,而一氧化氮及1,3-丁二烯等不饱和烃类物质则具有相对低的口腔残留效率。（2）在26 s内,随着烟气在口腔中停留时间的延长,醛酮类化合物的口腔残留效率一直快速上升,其余化合物的残留效率则在最初的10～14 s内快速上升,随后变化不明显。真空紫外光电离飞行时间质谱实现了从吸烟机和人体口腔中直接取样分析,可作为研究卷烟烟气中有害化学成分口腔残留的有效工具。

In order to determine the human buccal residues of harmful components from cigarette smoke, an on-line measurement system based on ultraviolet photoionization time-of-flight mass spectrometry（VUV-PI-TOFMS） technique was established. The photoionization mass spectra of fresh vapour phase mainstream cigarette smoke generated from a smoking machine directly or retained in the mouth of volunteers for different times were obtained. The retention efficiencies of the main toxic components from cigarette smoke in buccal cavity, such as nitric oxide（mass-charge ratio, m/z=30）, acetaldehyde（m/z=44）, 1,3-butadiene（m/z=54）, acetone（m/z=58）, isoprene（m/z=68）, benzene（m/z=78）, phenol（m/z=94） and ethylbenzene（m/z=106） were analyzed comparatively according to the results of qualitative analysis. The results showed that： 1） When cigarette smoke was retained in mouth for 2 s, the retention efficiencies of buccal cavity for aldehyde and ketone compounds were the highest, followed by phenol; while those for nitric oxide and unsaturated hydrocarbons were relatively lower. 2） Within 26 s, the longer the retention time, the higher the retention efficiencies for aldehyde and ketone compounds; and those for the other compound were also raised rapidly within the first 10-14 s, then nearly kept constant. VUV-PI-TOFMS achieved direct smoke sampling and analysis from both smoking machine and human buccal cavity, and hence is a powerful tool to study the buccal residues of harmful components from cigarette smoke.