Nicotine is considered " responsible" for the high rates of tobacco dependence and addiction, while the 4,000 other chemicals and compounds are " responsible" for the negative health effects associated with smoking.
在烟草的诸多成分中,尼古丁是让人们对烟草上瘾依赖的罪魁祸首;而其余的4000多种化学成分,会对身体健康有害。