[Health effects of chronic exposure to tobacco smoke on a non-smoker population].

A study devised to evaluate the effects of chronic exposure to tobacco smoke on the health of a population of non-smokers was conducted in a prison. Fourteen volunteers among male, non-smoking prisoners in good health and without history of lung disease were put for thirty days in a cell that was already occupied by three smokers. These subjects were examined on arrival and on the 30th day of their imprisonment. The examination included filling a questionnaire concerning daily habits and food, respiratory function tests, measurement of CO in the expired air, measurement of nicotine, cotinine, thiocyanates and cadmium concentrations in blood and in urine, and measurement of mutagenic substances excreted. The purpose of the study was to detect possible changes in the variables tested between the first and last days of confinement. No significant difference could be demonstrated within this lapse of time. These results are in agreement with the data available in the literature. In the present state of our knowledge, it is difficult to find evidence of a biological impact, notably on the concentrations of the specific indicators nicotine and cotinine, in subjects passively exposed to tobacco smoke.