Abstract
The purpose of the present work is to examine the effects of smoking on the amount of ethane expired from the human lungs and on lipid peroxidation in the human body. The amount of ethane in 1000ml of expired air was measured both in smokers and non-smokers. Results are as follows.
1. The amount of expired ethane in smokers (14 subjects) at least 4 hours afther smoking was 74.60±50.43pmol and that in non-smokers (19 subjects) was 24.49±10.24pmol.
2. Decreasing patterns of expired ethane after a single cigarette and those after refraining from smoking could be described by a two-compartment model in the following equation,
C=Ae-at+Be-bt
In this equation C is the amount of expired ethane at time t, A and B are the exponential coefficients and represent the amount of expired ethane in each component at time t=0, a and b are the exponential constants.
3. The amount of expired ethane after a single cigarette was 2438pmol for smokers and 1575pmol for non-smokers. The recovery time to the pre-smoking levels was about 3 hours for smokers and 4 hours for non-smokers.
4. Ethane from cigarette smoke disappeared from the lungs of smokers after refraining from smoking for 24 hours. The amount of expired ethane in smokers was more than that in non-smokers even after 24 hours, suggesting that smoking stimulated lipid peroxidation in the human body. The amount of ethane expired from the lungs of smokers was estimated to decrease to the level of non-smokers after 6 months abstinence.
