A new way of measuring the amount of pee in a swimming pool was developed at the University of Alberta by measuring the concentration of artificial sweeteners in the pool water. Artificial sweeteners are calorie free because the body cannot metabolize the molecules, meaning they pass through the body and get excreted in the same form. Artificial sweeteners like acesulfame potassium (Ace-K) are also universally used in most foods and drinks. The study found that an average commercial size pool contains about 20 gallons of urine and this goes up almost triple in pools commonly used by competitive swimmers. As the pool water goes unchanged for a long period of time and more people use it, the urine content increases (Blackstock,2017). YUCK!
Along with artificial sweeteners, urine and sweat contain uric acid. Although uric acid at this concentration is not dangerous to the body, the combination of the nitrogen in uric acid and chlorine makes volatile disinfection byproducts (DBP’s) such as cyanogen chloride (CNCL). Cyanogen chloride is considered an agent of chemical warfare and causes irritation in the eyes, nose, and lungs. The classic pool smell is the smell of cyanogen chloride, not just chlorine.
When CNCL is used as a chemical weapon, it causes disorientation and death in victims by affecting the respiratory and nervous systems. The initial irritation of chemoreceptors in the trachea and lungs causes violent coughing followed by shallow gasping. Eventually, the sensory surfaces are damaged and coughing stops, but the alveolar surface also gets damaged leading to a decrease in oxygen and carbon dioxide transfer. The lack of CO2 expiration leads to a buildup of acid in the circulatory system which leads to vomiting to compensate for the acidity of the blood. In the blood, CNCL is quickly metabolized by the liver but becomes Hydrogen Cyanide, an even more toxic molecule. HCN can cause damage to the central nervous system such as blindness, paralysis, and loss of reflexes (Aldridge,1946). Ultimately, victims usually die horribly, which is why chemicals like these are banned from use in wars.
Various news articles published after Michael Phelps claimed that every swimmer pees in pools had headlines like “Peeing in pools is chemical warfare.” Thankfully, cyanogen chlorine in pools is nowhere near the concentration needed to cause these effects. Although it will not instantly kill you, higher rates of asthma and bladder cancer have been seen among frequent swimmers. The DBP’s will also cause slight irritation of the eyes, skin, and nose. Ultimately, you are more likely to die from drowning, being killed by your friend for peeing in the pool, or fecal bacteria in the pool (a whole different story) than being killed from the pee in the pool.
Works Cited:
Aldridge, W. N., & Evans, C. L. (1946). The Physiological Effects And Fate Of Cyanogen Chloride. Quarterly Journal of Experimental Physiology and Cognate Medical Sciences,33(4), 241-266. doi:10.1113/expphysiol.1946.sp000908
Blackstock, L. K., Wang, W., Vemula, S., Jaeger, B. T., & Li, X. (2017). Sweetened Swimming Pools and Hot Tubs. Environmental Science & Technology Letters, 4(4), 149-153. doi:10.1021/acs.estlett.7b00043
E, Y., Bai, H., Lian, L., Li, J., & Blatchley, E. R.
(2016). Effect of chloride on the formation of volatile disinfection byproducts
in chlorinated swimming pools. Water Research, 105, 413-420.
doi:10.1016/j.watres.2016.09.018
This is honestly quite frightening... and definitely prompted me to research cyanogen chloride some more. It turns out that studies have linked heated pools (and their cyanogen chloride contents) to adolescent idiopathic scoliosis (AIS). More specifically one study's neuropathic hypothesis investigates the effects of cyanogen chloride exposure on infants and possible association of AIS incidence. What I found most interesting was the proposed mechanism by which cyanogen chloride makes contact with a baby's central nervous system. The chemical is especially dangerous to infants because blood-brain barriers of an infant are not completely developed leaving the child more susceptible to these kinds of exposures... scary! Moral of that story - don't take your infant into the kiddy pool!
ReplyDeleteReference:
McMaster, M. E. (2011, October 05). Heated indoor swimming pools, infants, and the pathogenesis of adolescent
idiopathic scoliosis: a neurogenic hypothesis. Retrieved December 03, 2017, from https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-10-86
Regarding your first paragraph, how can researchers measure the amount of pee in the pool simply from the amount of artificial sweeteners? This would be a hard way to measure it since people have varying diets that may not include artificial sweeteners.
ReplyDeleteDigressing, this was a really interesting read. My initial question was "how can swimmers protect themselves from cyanogen chloride?" but later read that the concentrations would have be significantly higher for there to be a significant health threat. While I was unable to find swimmers dying from DBP's, I did find that minnows also suffered from DBP's and DBP's were the principal toxic agent in sewage. The residual chlorine concentrations that produced a 100 percent kill was .16 and .21 mg/l. While uric acid and chlorine may not be an issue for swimmers, it could be a major issue for an ecosystem but we'll save that for another blog post.
Reference:
Zillich, J. A. (1972). Toxicity of combined chlorine residuals to freshwater fish. Journal (Water Pollution Control Federation), 212-220.