Disinfection Agents

The agents that can be used to disinfect water include (1) chlorine, (2) chloramines, (3) ozone, (4) chlorine dioxide, (5) ultraviolet radiation, (6) membrane filtration to remove pathogens, and (7) miscellaneous agents including the evolving use of ferrate (iron(VI)). Of these, chlorine and chloramines have been the most popular, but are becoming less so because of the by-products 

The physical process of filtration is rather effective in removing pathogens from water. During the 1800s, before chlorine came into widespread use, filtration with simple sand filters employed in just a few cities cut down significantly on the incidence of waterborne cholera in those cities. With modern membrane technology (see Section 5.10), ultrafiltration can remove even viruses from water. Small amounts of chlorine or chloramines (see Section 5.11.3) can be added to maintain sterile water in distribution systems, but much less of these agents are required for membrane-filtered water than are required for total disinfection. 

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Table 6. Therapeutants and Disinfecting Agents Approved for Use in United States Aquaculture ...

Disinfectants. Several disinfecting agents can be used in hatcheries and two are of particular interest. Because they are not considered dmg or food additive uses by FDA, povidone—iodine compounds can be used to disinfect the surface of eggs (9). Benzalkonium chloride [68424-85-1] and benzethonium chloride (quaternary ammonium compounds), are allowed at 2 mg/L by FDA to disinfect water containing fish. These compounds are also known to have therapeutic properties, especially against external bacteria (9). 

Water Treatment Compounds. Like the disinfecting agents, several water treatment compounds are used in aquaculture. Of particular interest is potassium permanganate which is exempted from registration by EPA when used as an oxidizer or detoxifier and can control certain parasites, external bacteria, and possibly fungi (9). 

The use of UV light has been selected as disinfection agent in this case study. The advantages of this technique have been explained previously [27], Total inactivation of the E. coll present in the WWTP effluent was achieved, as can be seen in Table 4 and pressure drop in the water line was increased in 0.1 bar. 

Chlorine and iodine have been used extensively since their introduction as disinfecting agents in the early 19th century. Preparations containing these halogens such as Dakin s solution and tincture of iodine were early inclusions in many pharmacopoeiae and national formularies. More recent formulations of these elemens have improved activity, stability and ease of use. 

Used industrially as a cleaning agent, disinfecting agent, insecticide, to etch glass, and as a welding flux. 

Benzenoids, aroma chemicals, 3 241 Benzethonium chloride cosmetic surfactant, 7 835t disinfecting agent for aquaculture in U.S., 3 213t Benzidine, 9 270, 448... 

Dicyclopentadiene resins, 20 114 formulation of, 20 103-104 Dicyclopentadienylmagnesium, 25 120 Didecyl dimethylammonium chloride (Sanaqua), disinfecting agent for aquaculture in U.S., 3 205t, 212t 2,6 -D ideoxy- 3- C-methyl- 3- O -methy 1-L-ribohexose, 4 713 Di(diacyl peroxides), 18 476 Die attach process, 17 830 Die casting... 

Preservative/antimicrobial preservative, antimycotic agent, bacteriophage control agent, chemosterilant/wine maturing agent, disinfection agent... 

CN131 Bamabe, W., T. de Mendonca Neto, F. C. Pimenta, L. F. Pegoraro, and ]. M. Scolaro. Efficacy of sodium hypochlorite and coconut soap used as disinfecting agents in the reduction of denture stomatitis. Streptococcus mutans and Candida albicans. J Oral Rehabil 2004 31(5) 453-459. 

Disinfectants are strong chemical agents that inhibit or kill microorganisms (Table 50-1). Antiseptics are disinfecting agents with sufficiently low toxicity for host cells that they can be used directly on skin, mucous membranes, or wounds. Sterilants kill both vegetative cells and spores when applied to materials for appropriate times and temperatures. Some of the terms used in this context are defined in Table 50-2. 

Materials used must cleaned and disinfected with the usual cleaning and disinfecting agents. Friction in the transport system must not cause particles. Electric motors without ventilators must be used and the sensors installed must be resistant to the cleaning and disinfecting agents. In general, every process must be reproducible, documented and validated. 

A warm solution of baking soda and water is suitable for many cleaning needs and can be combined with white natural vinegar, for a good disinfecting agent. 

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