Turner Claire, Spanel Patrik, Smith David
Cranfield University, Silsoe, Bedford, MK45 4DT, UK.
Physiol Meas. 2006 Jul;27(7):637-48. doi: 10.1088/0967-3334/27/7/007. Epub 2006 May 3.
Selected ion flow tube mass spectrometry, SIFT-MS, has been used to monitor the volatile compounds in the exhaled breath of 30 volunteers (19 male, 11 female) over a six-month period. Volunteers provided breath samples each week between 8:45 am and 1 pm (before lunch), and the concentrations of several trace compounds were obtained. In this paper the focus is on methanol in breath. The median methanol level determined using the H(3)O(+) precursor ions for all samples was 461 parts-per-billion (ppb), the concentrations for all the samples ranging from 32 to 1684 ppb. The distribution of breath methanol concentration is seen to be log-normal for this healthy population; the geometric mean was 450 ppb, close to the median value, and the multiplicative (geometric) standard deviation was 1.62. Breath methanol is not correlated with age, breath ethanol or ethanol consumed in the previous 24 h, but there was an inverse correlation with body mass index (BMI) for the cohort of volunteers recruited for this study. Observed breath methanol levels are well compatible with the previously published blood methanol levels. Some tentative suggestions are made concerning the origin of endogenous methanol.
选择离子流管质谱法（SIFT-MS）已被用于在六个月的时间内监测30名志愿者（19名男性，11名女性）呼出气体中的挥发性化合物。志愿者在每周上午8:45至下午1点（午餐前）提供呼气样本，并获得了几种痕量化合物的浓度。本文重点关注呼出气体中的甲醇。使用H(3)O(+)前体离子测定的所有样本中甲醇的中位数水平为461十亿分之一（ppb），所有样本的浓度范围为32至1684 ppb。对于这个健康人群，呼出气体中甲醇浓度的分布呈对数正态分布；几何平均值为450 ppb，接近中位数，乘法（几何）标准差为1.62。呼出气体中的甲醇与年龄、呼出气体中的乙醇或前24小时摄入的乙醇无关，但在本研究招募的志愿者队列中，与体重指数（BMI）呈负相关。观察到的呼出气体中甲醇水平与先前发表的血液甲醇水平非常吻合。关于内源性甲醇的来源提出了一些初步建议。
