Accidentally swallowing pool water is common, especially for children, and is usually harmless. However, pool water contains a mix of chemical disinfectants and potential biological contaminants that can pose risks to the digestive tract. The body’s reaction depends on the amount ingested and the pool’s cleanliness. While a small gulp likely causes no lasting harm, it is important to understand the potential for both immediate chemical irritation and delayed biological infection.
Acute Irritation from Pool Chemicals
The immediate, unpleasant taste and sensation come from the chemicals used to keep the water sanitary. Chlorine, the primary disinfectant, reacts with organic matter introduced by swimmers, such as sweat, oils, and urine. This reaction creates byproducts known as chloramines, which are responsible for the strong, “chemical” smell often associated with pools.
Ingesting water with a high concentration of these chloramines can lead to acute, short-term irritation of the upper digestive system. Symptoms may include mild nausea, a burning sensation in the throat, and stomach upset. If a larger volume of poorly maintained pool water is swallowed, the chemical imbalance can sometimes induce vomiting as the body attempts to expel the irritant. These chemical effects are transient, resolving quickly once the body has processed the irritant.
The Risk of Recreational Water Illnesses (RWIs)
The greater concern following the ingestion of pool water comes from biological contaminants, which can cause illnesses referred to as Recreational Water Illnesses (RWIs). These infections are spread when water contaminated with human or animal feces is swallowed. RWIs are often gastrointestinal, causing symptoms like prolonged diarrhea, stomach cramps, and fever.
The most notorious RWI pathogen found in pools is the parasite Cryptosporidium, often called “Crypto.” This parasite is highly resistant to chlorine, protected by a tough outer shell that allows it to survive for days even in properly treated water. This resistance means that a fecal accident from an infected person can contaminate a pool for a significant period.
Other common pathogens include the parasite Giardia, bacteria like E. coli, and viruses like norovirus, all transmitted through contaminated water. A key characteristic of RWIs is the delayed onset of symptoms, which distinguishes them from immediate chemical irritation. For instance, symptoms of cryptosporidiosis can appear 5 to 7 days after exposure, while giardiasis may take 7 to 14 days to manifest.
When chlorine reacts with organic matter like sweat or urine, its effectiveness is compromised, using up the disinfectant needed to kill germs. This allows chlorine-resistant organisms to persist and increases the risk of infection from swallowing contaminated water.
When To Contact a Healthcare Provider
For mild, acute symptoms such as transient nausea or a single episode of vomiting, home care focused on rest and hydration is usually sufficient. However, several warning signs should prompt a call to a healthcare provider. Persistent vomiting or an inability to keep fluids down is serious, particularly in children, due to the risk of dehydration.
Medical attention is necessary for symptoms that are severe or prolonged, suggesting a biological infection. These include high fever, severe abdominal pain, or diarrhea lasting more than a couple of days. Bloody diarrhea requires immediate medical evaluation. When speaking with a doctor, mention the recent pool water ingestion and the location of the exposure, as this information can aid in diagnosis and treatment.