What are the health risks of public swimming pools? Personal protection is the most important thing!

Map: Zhang Wenting

Swimming can improve a person's cardiopulmonary endurance and body flexibility, and improve a person's body fat percentage. However, swimming pools are public places, and there are many complex health factors. If you do not pay attention to hygiene, you may be infected with diseases during swimming. So how can we achieve both physical exercise and reduce health risks during swimming?

Major health risks of swimming

Pool water is the main source of health risks during swimming.

Swimming pool water is in direct contact with the human body, and human metabolites (especially urine and sweat) and applied cosmetics will enter the pool water, creating a good environment for the reproduction of microorganisms in the pool water. At the same time, since there may be bacteria and viruses in the water that cause diarrhea, red eyes and respiratory diseases, these pathogens cannot be removed by the swimming pool water treatment system. This results in swimmers suffering from red eyes, sinusitis, otitis media, viral upper respiratory tract infections and other diseases after swimming in swimming venues with poor sanitary conditions. Therefore, swimming pool water must be disinfected to prevent the spread of diseases and protect the health of swimmers.

Common methods of disinfection of swimming pool water

Currently commonly used disinfection methods include chlorination, ozone, chlorine dioxide, ultraviolet rays and bromine products. Some swimming pools also use metal ion disinfection, such as silver ions, but the whole set of equipment is very expensive and rarely used in China.

Chlorination disinfection is the use of chlorine gas or chloride to kill bacteria and viruses by releasing hypochlorous acid after reaction with water. Chlorination disinfection has a long history and was first used for the disinfection of drinking water. Chlorination disinfectants include chlorine and its products, such as liquid chlorine, calcium hypochlorite, sodium hypochlorite, sodium dichloroisocyanurate and trichloroisocyanuric acid. Liquid chlorine is a liquid obtained by liquefying chlorine gas. The effective chlorine content is nearly 100%. It is usually used in large commercial swimming pools. Although it is relatively cheap, it is dangerous and has a high odor, so it is rarely used. Sodium hypochlorite (NaClO) is commonly known as high-efficiency bleaching powder. The commercially available agent contains 10% to 15% effective chlorine. It is relatively cheap and easy to obtain. It is a disinfectant with a high frequency of use. Trichloroisocyanuric acid (TCCA) is commonly known as strong chlorine essence. The effective chlorine content is 85% to 95%. It is an organochlorine bactericidal disinfectant that can effectively and quickly kill various bacteria, fungi, spores, molds, Vibrio cholerae and algae. It has stable properties and less irritation to human eyes and skin. Therefore, trichloroisocyanuric acid is now mostly used as a disinfectant in swimming pool water.

Health hazards in swimming pools

During the actual use of swimming pools, the disinfectant in the swimming pool water will change due to factors such as differences in the venue's hygiene management conditions, changes in the number of swimmers, pool water temperature and water change rate.

If the disinfectant content is too low, the pool water cannot be effectively disinfected and is prone to breeding microorganisms. If the content is too high, it will irritate the human skin and mucous membranes and corrode the human skin and mucous membranes. I believe everyone has experienced this situation. After staying in the water for a long time, the eyes will turn red, the skin on the hands will become wrinkled and white, and the hair will be very frizzy. This is the "chlorine" in the water! Disinfectants are generally added to swimming pools, and disinfectants are strong oxidants that have a strong damaging effect on the skin and hair. This is also commonly known as "chlorine damage." At the same time, during swimming, human metabolites and sunscreens will enter the pool water and react with disinfectants to form disinfection by-products, which will also affect the health of swimmers.

Take personal protection when swimming

Don't forget personal protection when swimming. The Chinese Center for Disease Control recommends the following aspects: Wear a swimming cap, waterproof glasses, nose plugs, and ear plugs. When swimming, do not rub your eyes directly with your hands after the goggles get wet. Rinse your eyes and goggles with clean water in time. If you choke on water while swimming, rinse your mouth with clean water in time.

Eliminate uncivilized behavior

It is worth noting that the following uncivilized behaviors should be avoided during swimming, including not showering before entering the pool, not wearing a swimming cap, not soaking feet, spitting in the pool, urinating in the pool, and scrubbing after entering the pool.

In addition, swimmers should not swim for too long or too frequently, otherwise some people with sensitive constitutions may suffer from skin allergies. (Comprehensive information from the WeChat public account of the China Centers for Disease Control and Prevention)