What kind of gas can cause lung and skin irritation?

• A. Ammonia
• B. Chlorine
• C. Radon
• D. Oxygen

Answer: (B)

Gases that irritate the lungs and skin do so by reacting with moisture on mucous membranes to form substances that burn tissue. Chlorine gas is a prime example: when it dissolves in water in the eyes, nose, or lungs, it forms hydrochloric acid and hypochlorous acid, which inflame and damage airway linings and skin. This leads to coughing, chest tightness, eye irritation, and skin burns. Ammonia can also cause irritation, but chlorine is the classic gas associated with both respiratory and dermal irritation at exposure levels seen in water treatment contexts. Radon mainly causes long-term cancer risk rather than acute irritation, and oxygen at normal concentrations does not irritate the skin or lungs.