Health & Safety Chlorine can be harsh for those with sensitive skin or eyes, or those who have breathing conditions such as asthma. Bromine is a great alternative because it's less abrasive, less chemical-smelling, and less likely to trigger asthma attacks.

In the context of pool and spa maintenance in 2026, neither chemical is inherently "more harmful" than the other when used correctly, but they interact with the body differently. Chlorine is a more aggressive oxidizer; it is very effective at killing bacteria but creates "chloramines" as it works, which cause the strong "pool smell" and can irritate the eyes, skin, and lungs (especially for those with asthma). Bromine is generally considered gentler on the skin and eyes because its byproduct, "bromamines," remains an effective sanitizer and doesn't have a harsh odor. However, a specific reaction known as "Bromine Itch" (a form of contact dermatitis) is more common with bromine than with chlorine, especially in hot tubs where the chemical is more concentrated. Environmentally, bromine is more stable at high temperatures, which is why it's preferred for spas, but it is highly sensitive to UV light; without a stabilizer, sunlight can destroy 50% of a pool's bromine in just two hours, making it less efficient for outdoor use. In terms of "harm," the biggest risk for both is improper handling of the raw chemicals (concentrated tablets or liquid), which can cause severe chemical burns and respiratory distress if inhaled.