Ammonium disinfectants

Selective media for pseudomonads. These media depend on the relative resistance of pseudomonads to the quaternary ammonium disinfectant cetrimide. In some recipes the antibiotic nalidixic acid (Chapter 5) is added, to which pseudomonads are also resistant. 

The chemical modification of CS biopolymers via reductive amination, to yield alkylated CS derivatives, and further quaternisation result in very efficient antibacterial materials the degree of activity is correlated to the length of the alkyl chain and bacterial strain. The most active CS derivatives are more selective at killing bacteria than the quaternary ammonium disinfectants, cetylpyridinium chloride and benzalkonium chloride, and AMP. Vanillin can be used as a crosslinker of CS nsing this approach, functionalised antimicrobial polymers based on CS, vanillin. Tween 60 and so on may be easily prepared. Imino-CS biopolymer films, prepared by the acid condensation of the amino groups of CS with various aldehydes, can be used as functional biodynamic materials. 

Serrano LJ (1972) Dermatitis and death in mice accidentally exposed to quaternary ammonium disinfectant. J Am Vet Med Assoc 161 652-655... 

The threat of accidental misuse of quaternary ammonium compounds coupled with potential harmful effects to sensitive species of fish and invertebrates has prompted some concern. Industry has responded with an effort to replace the questionable compounds with those of a more environmentally friendly nature. Newer classes of quaternaries, eg, esters (206) and betaine esters (207), have been developed. These materials are more readily biodegraded. The mechanisms of antimicrobial activity and hydrolysis of these compounds have been studied (207). AppHcations as surface disinfectants, antimicrobials, and in vitro microbiocidals have also been reported. Examples of ester-type quaternaries are shown in Figure 1. 

Alkylbenzyldimethyl quaternaries (ABDM) are used as disinfectants (49) and preservatives. The most effective alkyl chain length for these compounds is between 10 and 18 carbon atoms. Alkyltrimethyl types, alkyl dimethylbenzyl types, and didodecyl dimethyl ammonium chloride [3401-74-9] exhibit excellent germicidal activity (151—159). Dialkyldimethyl types are effective against anaerobic bacteria such as those found in oil wells (94—97). One of the most effective and widely used biocides is didecyl dimethyl ammonium chloride [7173-57-5]. 

Disinfection destroys pathogenic organisms. This procedure can render an object safe for use. Disinfectants include solutions of hypochlorites, tinctures of iodine or iodophores, phenoHc derivatives, quaternary ammonium salts, ethyl alcohol, formaldehyde, glutaraldehyde, and hydrogen peroxide (see Disinfectants AND antiseptics). Effective use of disinfected materials must be judged by properly trained personnel. 

Agrochemical Products. Hydrazones of vanillin have been shown to have a herbicidal action similar to that of 2,4-D, and the zinc salts of dithiovanillic acid. Made by the reaction of vanillin and ammonium polysulfide in alcohoHc hydrochloric acid, dithiovanillic acid is a vulcanization inhibitor. 5-Hydroxymerciirivanillin, 5- a cetoxym erci iri va n ill in, and 5-ch1oromercurivani11in have been prepared and found to have disinfectant properties. 

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). 

Whereas these preparations do not possess the high bacteriostatic activity of quaternary ammonium germicides, they have the alternate advantage of being rapidly functional in acid solution. In comparative experiments of several different disinfectants, the acid—anionic killed bacteria at lower concentration than five other disinfectants. Only sodium hypochlorite and an iodine product were effective at higher dilution than the acid—anionic. By the AO AC use dilution test, the acid—anionic killed Pseudomonas aeruginosa at 225 ppm. Salmonella choleraesuis at 175 ppm, and Staphylococcus aureus at 325 ppm (172). 

Alkyl ammonium chloride (quaternium-15). Acts as a surfactant, disinfectant, and deodorant. 

Viruses that contain hpid are inactivated by organic solvents such as chloroform and ether. Those without hpid are resistant to these agents. This distinction has been used to classify virases. Many of the chemical disinfectants used against bacteria, e.g. phenols, alcohols and quaternary ammonium compounds (Chapter 10), have minimal virucidal activity. The most generally active agents are chlorine, the hypochlorites, iodine, aldehydes and ethylene oxide. 

In disinfection of instruments, the chemicals used must not adversely affect the instruments, e.g. cause corrosion of metals, affect clarity or integrity of lenses, or change texture of synthetic polymers. Many materials such as fabrics, rubber, plastics are capable of adsorbing certain disinfectants, e.g. quaternary ammonium compounds (QACs), are adsorbed by fabrics, while phenolics are adsorbed by rubber, the consequence ofthis being a reduction in concentration of active compound. A disinfectant can only exert its effect ifit is in contact with the item being treated. Therefore access to all parts of an instrument or piece of equipment is essential. For small items, total immersion in the disinfectant must also be ensured. 

Chemical disinfectants are limited in their use as air sterilants because of their irritant properties when sprayed. However, some success has been achieved with atomized propylene glycol at a concentration of 0.05-0.5 mgH and quaternary ammonium compounds (QACs) at 0.075% m be used. For areas which can be effectively sealed off for fumigation purposes, formaldehyde gas at a concentration of 1-2 mg H of air at a relative humidity of 80-90% is effective. 

Jimenez, L. and Chiang, M. (2006). Virucidal activity of a quaternary ammonium compound disinfectant against feline calicivirus A surrogate for norovirus. Am. J. Infect. Control 34, 269-273. 

Solomon, E. B., Fino, V., Wei, J., and Kniel, K. E. (2009). Comparative susceptibilities of hepatitis A virus, feline calicivirus, bacteriophage MS2 and bacteriophage PhiX-174 to inactivation by quaternary ammonium and oxidative disinfectants. Int. J. Antimicrob. Agents 33, 288-289. 

For disinfection the water should be clear and free of suspended material because they will react with some disinfectants. This will be discussed under quaternary ammonium salts. 

Surface disinfectants Compounds containing phenolics, chlorhexidine (not effective against bacteria spores), quaternary ammonium salts (additional activity if bis-n-tributyltin oxide present), hypochlorites such as household bleach, alcohols such as 70-95% ethanol and isopropyl (not effective against bacteria spores), potassium peroxymonosulfate, hydrogen peroxide, iodine/iodophores, and triclosan. 

Uses Manufacture of viscose rayon, cellophane, flotation agents, ammonium salts, carbon tetrachloride, carbanilide, paints, enamels, paint removers, varnishes, tallow, textiles, rocket fuel, soil disinfectants, electronic vacuum tubes, herbicides grain fumigants solvent for fats, resins, phosphorus, sulfur, bromine, iodine, and rubber petroleum and coal tar refining solvent and eluant for organics adsorbed on charcoal for air analysis. 

The most common disinfectants in use nowadays are sodium hypochlorite, peracetic acid, ammonium quaternary salts, aldehydes, alcohols and phenol compounds. However, according to [25], all disinfectants require special attention. Indeed, glutaraldehyde, used widely in the past but now generally discarded in favour of compounds with a smaller impact on WWTP biological processes, has been found in concentrations ranging from 0.5 to 3.72 mg [15]. Moreover, triclosan, a common detergent and antimicrobial agent found in many personal care... 

Other disinfectants include quartemary ammonium compounds (QACs) such as benzalkonium chloride (BACl) and didecyldimethylammonium chloride (DDMAC). Disinfectants have been shown to denitrifying bacteria at concentrations as low as 1-2 ng L (Kiimmerer, 2004b). QACs are specifically not used for disinfecting clothing, but their use is central in other purposes. Triclocarban and triclosan have an aromatic structure that is rich in chlorides, which contribute to their persistence in the environment. QACs are also quite persistent in the environment (Al-Ahmad et al., 2000). Other disinfectants include chloramines and 1,3-dichlorosucyanuric acid as well as PVP-iodide-based disinfectants. 

The use of disinfectants such as triclosan and quaternary ammonium compounds and triclosan in homes and hospitals also leads to an enhanced selection for antibiotic-resistant bacteria (Russell, 2000 Kiicken et al., 2000 McMurray et al., 1998). Besides introducing resistance to bacteria, some antibiotics can also impose other effects. For example, a recent study by Vehcer et al. (2004) reported an intriguing association between cumulative exposure to all classes of antibiotics and breast cancer. Floroquinolones have also been imphcated in inducing tensions in the cartilage of immature animals (Hunt et al., 2002) and are generally deemed unsuitable for pediatric use. However, their presence in the environment can inadvertently introduce them to such susceptible individuals. 

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