Department of Social Medicine, Saga Medical School, 5-1-1 Nabeshima, Saga 849-8501, Japan.
Environ Health Prev Med. 2013 May;18(3):244-50. doi: 10.1007/s12199-012-0307-5. Epub 2012 Sep 26.
Measuring urinary cotinine is a popular and established method of biologically monitoring exposure to tobacco smoke. However, the lower detection limit of cotinine often impedes the evaluation of passive (second-hand) smoking and this, together with unconverted nicotine, does not reflect actual levels of exposure. Furthermore, a portion of the Japanese population might have decreased ability to metabolize nicotine. The present study was therefore carried out to validate the simultaneous analysis of total concentrations of free nicotine and cotinine and their glucuronides to determine actual levels of voluntary and involuntary exposure to cigarette smoke.
Urine samples from 118 Japanese smokers and 117 non-smokers were analyzed using gas chromatography-mass spectrometry. Voluntary and involuntary smoking status was self-reported and workplace smoking restrictions were objectively evaluated.
The integrated sum of all concentrations showed 2.2- and 2.4-fold higher total levels (free and glucuronide) of nicotine and cotinine relative to the free levels. Median (quartiles) of total nicotine and cotinine were 1635 (2222) and 3948 (3512) ng/mL in smokers, and 3.5 (5.3) and 2.8 (4.2) ng/mL in non-smokers. Concentrations of urinary nicotine were higher than those of cotinine in 21 % of smokers and in 54 % of non-smokers. Nicotine and cotinine levels were significantly associated with a smoking habit, as well as being significantly associated with the workplace and home environments of non-smokers.
The present method can monitor voluntary and involuntary exposure to tobacco smoke. Measuring total urinary nicotine levels might be useful for analyzing exposure to cigarette smoke among non-smokers.
检测尿中可替宁是一种监测烟草烟雾暴露的常用且成熟的方法。然而，可替宁的检测下限往往会阻碍对被动（二手）吸烟的评估，且这一浓度与未代谢的尼古丁都无法反映实际的暴露水平。此外，部分日本人群可能存在尼古丁代谢能力下降的情况。因此，本研究旨在验证同时分析游离尼古丁和可替宁及其葡萄糖醛酸苷的总浓度，以确定自愿和非自愿吸烟的实际暴露水平。
采用气相色谱-质谱法对 118 名日本吸烟者和 117 名不吸烟者的尿液样本进行分析。吸烟状况为自我报告，工作场所的吸烟限制则进行客观评估。
所有浓度的积分总和显示，游离和葡萄糖醛酸苷形式的尼古丁和可替宁总浓度（游离浓度的 2.2-2.4 倍）更高。吸烟者中尼古丁和可替宁的总浓度（游离加葡萄糖醛酸苷）中位数（四分位数间距）分别为 1635（2222）和 3948（3512）ng/mL，非吸烟者分别为 3.5（5.3）和 2.8（4.2）ng/mL。在 21%的吸烟者和 54%的不吸烟者中，尿液中尼古丁的浓度高于可替宁。尼古丁和可替宁水平与吸烟习惯显著相关，与非吸烟者的工作场所和家庭环境也显著相关。
本方法可监测烟草烟雾的自愿和非自愿暴露。测量总尿尼古丁水平可能有助于分析非吸烟者的香烟烟雾暴露情况。
