Which term describes a chemical that can trigger an adverse immune response, causing hypersensitivity?

• A. Eye Hazards
• B. Sensitizer
• C. Reproductive Toxicants
• D. Aspiration Hazards

Answer: (B)

Some chemicals have the ability to provoke an immune response that leads to hypersensitivity. These substances are called sensitizers. After an initial exposure, the immune system becomes primed to recognize the chemical, and later exposures can trigger an exaggerated immune reaction, producing symptoms such as allergic contact dermatitis or occupational asthma. That’s why this term is the best fit: it specifically describes a chemical that can initiate that immune-mediated adverse effect. The other options describe hazards not tied to immune sensitization—eye hazards involve potential damage to the eyes, reproductive toxicants affect fertility or development, and aspiration hazards relate to the risk of lung injury if the substance is inhaled or swallowed. Common sensitizers include isocyanates, nickel, and certain epoxy resins, which illustrate how relatively small exposures can lead to hypersensitivity over time.