Final answer:
Carcinogens are substances that can cause cancer, while noncarcinogens do not increase the risk of cancer. Carcinogens may result in cancer by causing DNA mutations or metabolic disruptions resulting in uncontrolled cell growth.
Step-by-step explanation:
The difference between carcinogens and noncarcinogens is that carcinogens are agents that can cause cancer, while noncarcinogens are agents that do not cause cancer. To be more specific, a carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis, the formation of cancer. This usually happens because carcinogens can damage the genome or to the cellular metabolic processes. Various substances are classified as carcinogens, such as tobacco smoke which contains nicotine and formaldehyde, and exposure to it is the leading cause of lung cancer. Other examples include certain chemicals in processed foods and high-temperature cooking processes that form carcinogenic compounds. Noncarcinogens, on the other hand, do not increase the risk of cancer even if they may have other harmful health effects.
Answering the student's question, the correct statement would be: 1) Carcinogens are pollutants that can cause cancer, while noncarcinogens are pollutants that do not cause cancer.