The researcher found out that in the class of M.2/4 EP students of Boonwattana School with 27 students, 21 said that the hazardous effect of smoking is lung cancer, 5 said that it leads to preventable death and 1 said that it increases the chance of heart attack.
Therefore according to the M.2/4 EP students of Boonwattana School, lung cancer is the rampant hazardous effect of smoking.