Swimming pools and

Lithium Hypochlorite. Lithium hypochlorite [13840-33-0], LiOCl, is obtained from reaction of chlorine and an aqueous solution of lithium hydroxide. The soHd is usually obtained as a dry stable product containing other alkaH haHdes and sulfates (64). A product containing 35% available chlorine is used for sanitizing appHcations in swimming pools and in food preparation areas where its rapid and complete dissolution is important. The salt can also be obtained in higher purity by reaction of lithium hydroxide and hypochlorous acid (65). 

Toxicity of Chlorine Sanitizers. Chlorine-based swimming-pool and spa and hot-tub sanitizers irritate eyes, skin, and mucous membranes and must be handled with extreme care. The toxicities are as follows for chlorine gas, TLV = 1 ppm acute inhalation LC q = 137 ppm for 1 h (mouse) (75). The acute oral LD q (rats) for the Hquid and soHd chlorine sanitizers are NaOCl (100% basis) 8.9 g/kg (76), 65% Ca(OCl)2 850 mg/kg, sodium dichloroisocyanurate dihydrate 735 mg/kg, and trichloroisocyanuric acid 490 mg/kg. Cyanuric acid is essentially nontoxic based on an oral LD q > 20 g/kg in rabbits. Although, it is mildly irritating to the eye, it is not a skin irritant. A review of the toxicological studies on cyanuric acid and its chlorinated derivatives is given in ref. 77. 

Swimming Pool and Spa Industry Survey, The National Spa and Pool Institute, Alexandria, Va., 1993. 

Although pH determines the ratio of hypohalous acid to hypohaUte ion, the fraction of the total available halogen present as HOX is dependent on of the halamine as well as the concentration of excess amine. In the case of chloroisocyanurates, which are the most widely used /V-ch1oramine disinfectants in swimming pools and spas, the extent of hydrolysis at 1 ppm av CI2 (as monochloroisocyanurate) is - 34% but only - 1% when 25 ppm cyanuric acid is added (4). Nevertheless, effective disinfection can stiU occur with chloroisocyanurates if a sufficient FAC is maintained, eg, 1—3 ppm. The observed reduction in disinfection rate because of cyanuric acid (6) has been shown to be direcdy related to the concentration of HOCl formed by hydrolysis of chloroisocyanurates (10). 

High yields of NaOCl are obtained electrolyticaHy by oxidation of CT at dimensionally stable anodes (219). Sodium hypochlorite is prepared using small diaphragmless or membrane cells, with a capacity of 1—150 kg/d of equivalent CI2, which produce a dilute hypochlorite solution of 1—3 and 5—6 g/L from seawater and brine, respectively (see Chemicals from brine). They are employed in sewage and wastewater treatment and in commercial laundries, large swimming pools, and aboard ships. 

Applications. Lithium hypochlorite, first introduced in 1964, has limited use in swimming pool and spa sanitation and dry laundry bleaches. 

Acute toxicides (LD q rats) for CA and chloroisocyanurates are CA > 5.0, SDCC 1.67, PDCC 1.22, and TCCA 0.75 (126). A review of toxicological studies on CA and its chlorinated derivatives is given in Reference 127. These studies show that the compounds are safe for use in swimming pool and spa/hot tub disinfection, sanitizing, and bleaching appHcations when handled and used as directed. 

Most of the CA produced commercially is chlorinated to produce SDCC, SDCC-H, PDCC, TCCA, and the double salt TCCA4PDCC. These have become standard ingredients in formulations for scouring powders, household bleaches, institutional and industrial cleansers, automatic dishwasher compounds, and general sanitizers, and most importantly, in swimming pool and spa/hot tub disinfection. The choice of chloroisocyanurate for any particular... 

Sodium dichloroisocyanurate is used as a disinfectant in swimming pools and as a bleaching agent in household cleansers. 

Chlorine compounds are found all around the home. On the table is sodium chloride, ordinary table salt. In the kitchen and bath are chlorine scouring powders, and chlorine bleach is used in the laundry. Chlorine is used as a disinfectant in swimming pools, and in industry it is used to make paper. 

In addition to the use of chlorine as an antiseptic for swimming pools and drinking water, large amounts are used during industrial processes that produce paper, plastics, textiles, dyes, medicines, insecticides, solvents, and some paints. Following are some of the more important compounds of chlorine used in industries hydrochloric acid (HCl + H O), table salt (NaCl), chloroform (CHCL ), carbon tetrachloride (CCy, magnesium chloride (MgCl ), chlorine dioxide (CIO ), potassium chloride (KCl), and lithium chloride (LiCl). 

Sodium hypochlorite NaOCl is a strong oxidizer used in swimming pools, and when diluted to 5.25%, it is known as the laundry bleach Clorox. 

Nakajima M, Kawakami T, Niino T, Takahashi Y, Onodera S (2009) Aquatic fate of sunscreen agents octyl-4-methoxycinnamate and octyl-4-dimethylaminobenzoate in model swimming pools and the mutagenic assays of their chlorination byproducts. J Health Sci 55(3) 363-372... 

Verrucas are caused by the human papilloma virus. Verrucas are warts having a characteristic cauliflower-like appearance. Verrucas are contracted from swimming pools and public baths. They are painful when pressure is applied. Treatment involves removal of the hyperkeratolytic skin layers by the use of keratolytic agents such as salicylic acid. 

About one-third of the 40 million tons of chlorine produced annually goes to the manufacture of polyvinyl chloride, PVC, which is one of the most versatile of all plastics. PVC is ubiquitous, being used for pipes, flooring, electrical insulation, wallpaper, school supplies, swimming pools, and many other daily-use products. 

Ozone is used in the treatment of drinking water and in industries where high purity water is required (e.g., breweries, pharmaceuticals, and electronics). Ozone is also used in industrial wastewater pollution control, wastewater disinfection, and odor control in the treatment of process water, such as cooling tower water in the treatment of swimming pools and spas in pulp bleaching and in organic synthesis, as a selective oxidant. 

Ozone is more popular than chlorine for municipal drinking water in some western European countries, where it has been used for more than 80 years. It is widely used in indoor swimming pools and spas, and also in industry, such as fish farming, fruit and vegetable wash water, waste treatment, and chemical processes. 

Water in the swimming pool and snow on the ski slopes reflect sun s rays. At the same time, the swimmers and skiers absorb the sun s rays that strike them. Therefore, they get a double dose of energy from the sun. 

Apartments with special facilities (swimming pools and health clubs) are often available. 

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