Breath carbon monoxide concentration in cigarette and bidi smokers in India.

OBJECTIVE To measure and compare the breath carbon monoxide (CO) levels in cigarette and bidi smokers in India. METHODS Breath CO was measured in 389 smokers (241 cigarette smokers,148 bidi smokers) using portable breath CO analyser (Bedfont-England, Smokelyzer). Tobacco contents and length of single stick of different brands of cigarette and bidi were also measured. RESULTS Their mean age was 38.7 +/- 13.4 years. The average duration of smoking was 18.2 +/- 13.0 years. Average breath CO levels were 15.6 +/- 7.0 ppm in smokers and 4.07 +/- 1.16 ppm in non-smokers. Average breath CO level was significantly higher in bidi smokers (18.9 +/- 7.7 ppm) compared to cigarette smokers (13.6 +/- 5.8 ppm) when total consumption of cigarette/bidi was more than five pack-years (p = 0.002). Average tobacco weight of bidi (216.8 mg) was significantly less than cigarette (696 mg). CONCLUSIONS Bidi is equally or more harmful than cigarette smoking. One bidi may be considered to one cigarette for calculating "pack-years" of smoking.