RESUMEN
BACKGROUND: Tobacco consumption is a net increase in our areas. In Senegal, as in other African countries, sponsorship of cultural and sporting events in schools promote tobacco use among schoolchildren. Our objective was to assess the prevalence of tobacco in the French School of Jean Mermoz of Dakar by a survey completed by a measurement of carbon monoxide (CO) in expired air. METHODS: seven hundred forty-one students (n = 402 girls and n = 339 boys), aged 11 to 18 years of French and African cultures, participated in the study. A questionnaire with several items of smoking has been distributed to them . Two weeks after the collection of questionnaires, the CO measuring for all students was conducted. RESULTS: The prevalence of smoking in High School was 23.1% and smoking was found more in boys according to the questionnaire and piCO+TM with 13.7% and 7.1% respectively. It affected over the upper age class or equal to fifteen years. The most mentioned reason for the initiation of smoking (45.4% of smokers) was curiosity with a need to be free, followed by the influence of the environment famial (44.4%) and friendly (20.5%). The measurement of carbon monoxide showed that 12.4% of our subjects had a smoking profile with 8% light smoking, 1% moderate smoking, and severe smoking was 3% of our students. A significant difference (p = 0.0021) between the two prevalences was found. CONCLUSION: The carbon monoxide intoxication by tobacco use is responsible for microcirculatory accidents such as tissue hypoxia, whereas smoking affects young students, in which the phenomenon is more precocious. Thus it is urgent to establish a policy of tobacco control in schools.