Chlorine at the concentrations found in swimming pools does not reliably kill ticks. A standard pool maintains 1 to 3 parts per million of free chlorine, which is far too dilute to penetrate a tick’s natural defenses. Ticks can survive prolonged submersion in water, and the small amount of chlorine in a pool or hot tub adds very little threat to them.
Why Ticks Survive in Water
Ticks have a specialized breathing system that lets them extract oxygen while submerged. Their spiracular plates, the openings they breathe through, are lined with water-repellent structures that trap a thin film of air against the body. This film acts as a physical gill, pulling dissolved oxygen from the surrounding water and channeling it into the tick’s respiratory system. Researchers confirmed this mechanism, called plastron respiration, in the American dog tick and consider it likely present across hard tick species.
Because the air film resists wetting, simply dunking a tick underwater doesn’t suffocate it. The tick essentially carries its own air supply that continuously replenishes from the water. This is why flushing a tick down the toilet or dropping it in a glass of water often fails to kill it quickly. A tick submerged in plain water can survive for days.
Pool Chlorine vs. What It Takes to Kill a Tick
The chlorine levels in a residential swimming pool (1 to 3 ppm) are designed to kill bacteria and viruses, not arthropods with protective exoskeletons. Research on tick surface decontamination has used 5% sodium hypochlorite, which is roughly 50,000 ppm of available chlorine, thousands of times stronger than pool water. Even at that concentration, the solution was applied for a full five minutes primarily to strip bacteria from the tick’s surface, not necessarily to kill the tick itself.
In practical terms, swimming in a chlorinated pool after spending time outdoors will not kill any ticks that may have crawled onto your skin. A tick that’s already attached and feeding is even less vulnerable, since its mouthparts are embedded in your skin and its body is designed to resist environmental stressors. Hot tubs, despite being warmer, still use chlorine or bromine at concentrations far below what would affect a tick.
What Actually Kills Ticks
Heat is far more effective than chlorine. Putting clothes in a dryer on high heat for 10 minutes kills ticks on dry clothing. If clothes need washing first, use hot water. Cold and medium temperature water will not kill ticks. This is one of the most practical steps you can take after spending time in areas where ticks are common.
Alcohol is another option for individual ticks. Research has shown that wetting a tick’s spiracular plate with alcohol disrupts the plastron’s water-repellent properties, collapsing the air film and lowering survival rates. Dropping a removed tick into a small container of rubbing alcohol is a reliable way to kill it. You can also seal it between layers of tape or flush it, though flushing is slower and less certain.
What to Do After Swimming Outdoors
If you’ve been swimming in a natural body of water surrounded by grass, brush, or woods, the water itself offered you no protection against ticks. Ticks live in vegetation at the water’s edge, and they can attach while you’re walking to and from the water, sitting on the bank, or drying off on the grass.
Shower within two hours of coming indoors. Showering has been shown to reduce the risk of Lyme disease, likely because it washes off ticks that haven’t yet bitten and gives you a chance to spot ones that have. During or after your shower, do a full body check. Pay close attention to hidden spots: under your arms, behind your knees, around your ears, inside your belly button, along your hairline, between your legs, and around your waist. These are the warm, concealed areas ticks prefer.
Check children carefully, especially in and around the hair. Also examine any gear, towels, or clothing that touched the ground. Ticks can hitch a ride on these items and attach to someone hours later at home.
Removing an Attached Tick
If you find a tick that’s already biting, grab it as close to your skin as possible with fine-tipped tweezers and pull straight up with steady, even pressure. Don’t twist, crush, or try to burn it off. Don’t coat it in nail polish, petroleum jelly, or chlorine hoping it will back out on its own. These methods waste time and can cause the tick to regurgitate into the wound, increasing infection risk. Once removed, clean the bite area with rubbing alcohol or soap and water, then kill the tick by submerging it in alcohol or sealing it in tape.