Smoking is an addiction that is required by the laws of the country. Which do include many manufacturers and governments. But smoking is considered a major cause of many serious diseases, respiratory, heart and circulatory system. Toxic effects of smoking a mixture of toxins. The smoke that cigarette smoke inhaled through the mouth and nose to stick a cigarette mouth, pharynx, lung cancer risk of heart disease than people who do not smoke. And may harm the fetus.