Be careful about chlorine in pools: Chlorine Can Trigger Allergies, Asthma

January 26, 2023

For many kids, the smell of a chlorine pool triggers immediate sensations of joy because it means that soon they’ll be one with water, swimming and splashing and having a blast. But, those telltale fumes could also potentially trigger a whole lot more, like asthma.

A 2006 Belgian study showed that use of indoor chlorine pools especially by children younger than 7 promotes the development of childhood asthma. More disturbing still, the researchers found that the kids who swam most frequently had proteins associated with increased risk of asthma at levels similar to those found in regular smokers.

While initial assumptions were that indoor pools posed a greater threat than outdoor, a study released by the European Respiratory Society demonstrated that even regular use of outdoor chlorinated pools significantly increased the risk of developing asthma.

In response to this study, a review of all available evidence was conducted and the researchers concluded that while there are standards for the microbiological quality of the pool water, science-based standards for the quality of the air above the water are still needed. They discovered a vast knowledge gap about what chemicals might be volatilizing into the air, at what levels, and what that might mean for human health. The studies simply hadn’t been done.

More studies are needed indeed, but we do know that when chlorinated water comes into contact with hair, body products, sweat, saliva, or urine (regular ingredients at the public pool) it creates certain volatile disinfection by-products like chloroform (which is potentially carcinogenic and over time causes liver and kidney damage) and bromodichloromethane (which, again, has been linked to cancer and liver and kidney damage in animal studies).

What can you do to protect your kid’s health from chlorine fumes?

- Head to the beach.
- Limit (but don’t feel compelled to eliminate) swimming in indoor chlorine pools, especially if it’s your only option.
- Select pools with strict rules about bathing before swimming (and do your part to help keep them clean).
- Select less used pools or swim at times when there are fewer people there.
- Talk to management about the ventilation system, how often the pool is emptied (decreasing the organic materials that create the disinfection by-products), and options for safer maintenance.
- If you have your own pool, keep it chlorine-free.