Chlorination is the most common disinfection process in swimming pools. Which of the chemicals causes respiratory and eye irritation around swimming pools immediately after the disinfection process?

Correct option is C

Chloramines are by-products formed when chlorine reacts with nitrogenous compounds, such as ammonia, introduced into swimming pools via sweat, urine, or other contaminants. These compounds are responsible for causing respiratory and eye irritation among swimmers. Chloramines are volatile and can accumulate above the water surface, creating a noticeable and pungent “chlorine smell,” often mistaken for chlorine gas. Their irritating properties make them a health concern, especially in poorly ventilated indoor pools.
Key Explanation:
· Hypochlorous acid (a): A primary disinfectant in pools but does not cause significant irritation directly.
· Chlorine gas (b): Rarely present at significant levels in pools post-disinfection.
· Chloramines (c): These cause irritation and are the primary culprits of discomfort for swimmers.
· Chlorine dioxide gas (d): Unrelated to common pool disinfection methods and unlikely to cause irritation in swimming pools.
Information Booster:
1. Chloramines form due to inadequate pool maintenance or excessive organic contaminants.
2. Proper ventilation reduces the accumulation of chloramines above pool surfaces.
3. Effective pool management includes “superchlorination” to break down chloramines.
4. Indoor pools are more prone to chloramine buildup than outdoor pools.
5. Persistent exposure to chloramines may lead to conditions such as swimmer's asthma.
6. Regular testing and balancing of pool chemistry prevent chloramine formation.
Additional Knowledge:
· Hypochlorous acid (a): Hypochlorous acid is the active disinfectant formed when chlorine dissolves in water. It is effective against bacteria and viruses but is less volatile and does not directly irritate swimmers unless pH levels are not properly balanced.
· Chlorine gas (b): While toxic in high concentrations, chlorine gas is not typically released in pools unless there is an accident during chlorine storage or handling. Its presence in swimming pools is negligible under normal circumstances.
· Chloramines (c): These are classified into monochloramine, dichloramine, and trichloramine. Trichloramine is particularly volatile and is responsible for the strong chlorine-like smell and irritation. Managing swimmer hygiene and maintaining free chlorine levels reduce chloramine formation.
· Chlorine dioxide gas (d): Chlorine dioxide is a powerful disinfectant used in industrial water treatment but not in swimming pools due to its instability and specific handling requirements.
Key Points:
· Chloramines form from chlorine and ammonia, not from poor disinfection methods.
· The strong smell near pools often signals chloramine buildup, not excessive chlorine.
· Maintaining proper ventilation is as crucial as chemical balance in indoor pools.