Final answer:
The sticky black substance in tobacco smoke is called tar, which contains carcinogens that damage the lungs and increase the risk of cancer. Tobacco smoke has over 7,000 harmful substances, and second-hand smoke exposure carries serious health risks for nonsmokers and children.
Step-by-step explanation:
The sticky black substance in tobacco smoke that coats the inside of the airways and contains many carcinogens is known as tar. Tar is particularly dangerous because it not only damages the lungs' natural cleaning system by destroying or paralyzing the cilia but also causes the lungs to produce more mucus that can't be removed due to the damage. This leads to a persistent cough and an increased susceptibility to respiratory ailments.
Tobacco smoke is filled with over 7,000 substances, many of which are toxic, and it includes significant carcinogens such as benzopyrene, acrolein, and nitrosamines, along with radioactive isotopes like lead-210 and polonium-210. These compounds can cause mutations in the DNA of cells, leading to cancer. Exposure to second-hand smoke is similarly harmful, as it contains a blend of sidestream smoke from the burning cigarette and the smoke exhaled by smokers, which includes at least 250 toxic and carcinogenic compounds.
Children and nonsmokers living with smokers are at higher risk of developing health problems, such as lung cancer, respiratory infections, and complications with asthma due to second-hand smoke. Thus, it is crucial to understand the risks associated with tobacco smoke to take preventive measures.