Many different chemical substances cause cancer. Dozens of chemicals in tobacco smoke, including nicotine, have been shown to cause cancer ( Figure below ). In fact, tobacco smoke is one of the main sources of chemical carcinogens. Smoking tobacco increases the risk of cancer of the lung, mouth, throat, and bladder. Using smokeless tobacco can also cause cancer. Other chemicals that cause cancer include asbestos, formaldehyde, benzene, cadmium, and nickel.
Context: Jamal is a chemist that washes his hands every day with benzene in order to remove excess chemicals. Because of this, he has a high level of contact with benzene on a regular basis. Jamal's son, Chester, is also a chemist. However, Chester washes his hands with water, and as a result he has no contact with benzene.
Question: Who is at a higher risk for developing cancer?