Warmer spring days are here, and hopefully summer vacations are on the near horizon. Hot tub season is officially here. (Then of course there’s The Bachelorette starting up soon, which means a summer with lots of steamy moments in the hot tub, if not in real life then at least on reality television.
However, although it might sound relaxing to soak in a hot tub, how hygienic is it really? Can throwing a few chemicals into the tub really do the job? In order to find out, we asked a few experts to help us- Dr. Charles Gerba, professor of environmental studies and microbiology and HLA sequencing at the University of Arizona, and epidemiologist Michele Hlavsa, MPH, RN, who is also the healthy swimming chief at the Centers for Disease Control of Prevention.
You can actually pick up some pretty unappealing and potentially dangerous bugs from taking a dip in a hot tub, from the steamy environment surrounding it in addition to the water itself.
According to Hlavsa, the temperature of the water in a hot tub is warmer than a pool, which makes it harder to maintain the right disinfectant levels for killing some germs. Pseudomonas aeruginosa is one of the common germs. It can result in Pseudomonas folliculitis, which is a type of infection. This is what is known as hot tub rash, which you have probably heard of.
Pseudomonas aeruginosa is frequently found in soil and water. When the disinfectant levels in water goes down, it multiplies. However, it doesn’t always disappear again when the disinfectant levels increase again. Hlavsa says that at that point it remains in the water, waiting for the level to decrease once again so that it can multiply. Since people have a tendency to sit inside a hot tub for a fair amount of time, resulting in their skin getting exposed for quite some time to contaminated water.
According to the CDC, frequently the rash will be in the shape of the individual’s bathing suit. Itchy spots can develop into bumpy rashes and also blisters filled with pus around the hair follicles. This symptoms usually appear within a couple of days of being exposed.
Although hot tub rash does usually clear up all on its own without needing to be treated, there is a serious condition that could be potentially fatal that you need to be aware of. It is Legionnaires’ disease, which is a form of pneumonia. The germ Legionella causes this disease. This germ is in water, particularly warm water. It can also be inhaled from the mist or steam that surrounds a hot tub that is contaminated with this germ. Individuals with weakened immune systems, smokers and those over the the age of 50 are especially susceptible. According to Hlavsa, Legionella protects itself in a similar way in the water like Pseudomonas aeruginosa does. It can also cause Pontiac fever, which is a mild, flu-like illness.
According to the most recent report from earlier this year that was released by the CDC, there were 16 outbreaks that related to spas and hot tubs reported in 2009-2010 to the CDC. Out of these total reports, it was confirmed that 25 percent of them were caused by Legionella and 43.8 percent caused by Pseudomonas, or suspected to be.
In addition to pathogens found in water naturally, humans can introduce their own germs as well when dipping into hot tubs. According to Gerba, the average hot tub bather has around one tenth of one gram of feces inside his gluteal fold, or butt crack. So when there are five people in a hot tub, there one tablespoon of poop in there. He says that beyond it being gross, there is also a risk of diseases being transmitted if the levels of disinfectant are not safe.
Another thing to be concerned about is individuals urinating inside hot tubs (although it is hard to pinpoint exact numbers specifically for hot tubs, there was a poll where one out of five Americans admitted to peeing in swimming pools). Whenever urine, sweat and other waste mixes with chlorine, an irritant known as chloramine is created. This is what causes stinging, red eyes when you are swimming, says Hlavasa. Your respiratory tract can also be irritated. It’s very important that a hot tub not be used as a restroom. Chlroamines cause “chlorine smell.” This is a big red flag that the hot tub is contaminated.
Although many people do take a shower after going swimming, it is also important to bathe after being in a hot tub as well. Personal care products like sunscreen, makeup and lotion use up the water’s disinfectant, which makes it less effective when it comes to kill other bugs off. Gerba says, the disinfectant level drops right away when three people get into a hot tub. That’s why he says it’s better to have fewer people in a hot tub since this decreases how much disinfectant is needed.
So if you love hot tubs, what should you do?
Hlavsa recommends that you shouldn’t take any chances, and that you should purchase test strips at a pool supply store in your local area (she says 50 strips usually cost under $10). That way you’ll know before jumping in whether the water is safe or not. She says before you get in, just dip them in the water. The color of the pads change, and you can know what the disinfectant level is by the various colors. The water chemistry that the CDC recommends is: a pH of 7.2 to 7.8, bromine at 4-6 ppm (parts per million) and chlorine at 2-4 ppm. The hot tub’s temperature shouldn’t exceed 104 degrees F, there should be not odor and have smooth tiles. Don’t let water get into your mouth. The CDC has additional hot tub safety tips that you can review.