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.