Which term describes a substance that irritates tissue on contact but has minimal systemic effects?

• A. Irritants
• B. Secondary irritants
• C. Sensitizers
• D. Asphyxiants

Answer: (A)

When a substance primarily causes local irritation without spreading toxicity throughout the body, it is described as an irritant. Irritants affect tissues it touches—skin, eyes, or mucous membranes—producing redness, burning, or inflammation, but they don’t typically produce significant systemic effects unless exposure is extreme. This is different from sensitizers, which require an immune response and can trigger allergic reactions after repeated exposure, and from asphyxiants, which disrupt oxygen delivery or use in the body. A term like secondary irritants isn’t the standard way to describe this local, non-systemic effect, so the best fit is irritants.