Letter: safer cigarettes.
D002248:Carbon Monoxide / Q000032:analysis; D002273:Carcinogens; D006266:Health Education; D006801:Humans; D010947:Plants, Toxic; D012906:Smoke / Q000032:analysis; D000074606:Smoking Prevention; D014026:Nicotiana
D002273:Carcinogens; D012906:Smoke; D002248:Carbon Monoxide