Individuals who experience secondary exposure to health hazards and may face serious effects upon re-exposure are classified as?

Answer: B — Sensitizers

Individuals who experience secondary exposure to health hazards and may face serious effects upon re-exposure are classified as sensitizers. Sensitizers can provoke an allergic reaction after the initial exposure, meaning that subsequent exposures can lead to increasingly severe reactions. This characteristic is significant in managing and assessing risks associated with chemical exposure, particularly in workplace environments. For instance, a sensitizer may not cause an adverse reaction upon first contact but may lead to heightened sensitivity over time. This highlights the importance of identifying and controlling exposure to sensitizing agents, as individuals may not be aware of their developing allergic reactions until they occur. In contrast, asphyxiants primarily interfere with the body’s ability to take in oxygen, corrosives cause damage to living tissue through chemical reaction, and carcinogens are substances that promote the formation of cancer but do not necessarily result in immediate allergic reactions or sensitivity. Each of these categories pertains to different mechanisms of toxicity, emphasizing why sensitizers are the correct classification for individuals reacting to secondary exposures.