Disinfectants chemical groups

The following section presents in alphabetical order by chemical grouping the agents most often employed for disinfection, antisepsis and preservation. This information is summarized in Table 10.6. 

Formaldehyde and glutaraldehyde are used for disinfection or sterilization of instruments such as fiberoptic endoscopes, respiratory therapy equipment, hemodialyzers, and dental handpieces that cannot withstand exposure to the high temperatures of steam sterilization. They are not corrosive for metal, plastic, or rubber. These agents have a broad spectrum of activity against microorganisms and viruses. They act by alkylation of chemical groups in proteins and nucleic acids. Failures of disinfection or steri... 

A report released by the national environmental health group Women s Voices for the Earth (WVE) (htq> //www.womensvoices.org/wp-content/uploads/2010/05/ Disinfectant-OverkilLpdf) linked disinfectant chemicals with chronic illnesses and conditions such as asthma, hormone imbalance, and immune system problems in a report titled Disinfectant Overkill How Too Clean May Be Hazardous to Our Health, which cited more than 40 peer-reviewed reports and scientific studies. According to the report Triclosan and Triclocarban, two antibacterial disinfectants may have hormone-disrupting effects Triclosan adversely affects communication between cells in the brain and the heart while Triclocarban appears to amplify testosterone in the body (http //www.womensvoices.org/wp-content/uploads/2010/05/ Disinfectant-OverkilLpdf). The physical and chemical properties of disinfectants and their byproducts can influence their behavior in drinking water. 

The quaternary ammonium compounds (qv) are manufactured by the reaction of an alkyl halide with a tertiary amine. The alkyl halide may be short-chain, long-chain, or benzyl. Selection of a long-chain alkyl group yields structures with variable composition and greatly adds to the chemical complexity inherent in this group. Investigation of structure-activity relationships has led to claims for superior efficacy or compatibility, most notedly with anionic surfactants in disinfectant-detergent cleaner systems, of closely related compounds in the family. 

The Food Standards Code [10] is the main regulatory instrument which controls the quality of food, contaminant levels, approved additives, processing aids, sanitisers and disinfectants and these standards are performance based. If a chemical or a group of chemicals is covered by a food standard then they must only be used in food in accordance with the standard. However, if a chemical is not mentioned in a standard, then this does not preclude its use in food. For a new chemical not previously used in food production, it would be necessary for the supplier to undertake a detailed risk analysis of the product to demonstrate its safety and suitability. The assessment would need to consider both the toxicological profile of the chemical and the levels of human exposure that are likely to arise from residues in food. 

Phenol is an important industrial chemical. More than 3 billion pounds are produced each year. The major uses of phenol are as a disinfectant and in the production of polymers. Complex phenols, with multiple substituents and functional groups, are common in nature, although the simple phenols are seldom encountered. 

In 1974 it was discovered that the use of chlorine in the disinfection of water leads to the formation of a group of compounds referred to as the trihalo-methanes. This group of compounds includes chloroform, bromodichloromethane, dibromochlo-romethane, and bromoform. The relative concentrations of the members of this class depend on the concentration of bromide in the water being disinfected. In recent studies, it has become clear that the trihalomethanes are only one class of by-products and that there are small concentrations of a wide variety of chemicals produced with chlorination. However, it should be recognized that all chemical disinfectants are reactive compounds and, as a consequence, all will produce unintended by-products as a result of their use. 

The second category, hydroxy- and epoxy-containing acyl groups (and their esters), have numerous applications as chemical feedstocks in lubricants, paints and coatings, food and cosmetics emulsifiers, nylon synthesis, laxatives, disinfectants, etc. The utility of ricino-leic acid and its derivatives, for instance, the most commonly recognized member of this category, has existed for at least a century, demonstrated by US patents issued nearly 100 years ago, and 577 patents issued between the years 1990 and 2004. 

The new Directive describes biocides as chemical preparations containing one or more active substances that are intended to control harmful organisms by either chemical or biological, but by implication, not physical means. The classification of biocides is broken down into four main groups — disinfectants and general biocides, preservatives, pest control and other biocides and these are further broken down into 23 separate categories. 

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