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A biocide is defined in the European legislation as a chemical substance or microorganism intended to destroy, deter, render harmless, or exert a controlling effect on any harmful organism by chemical or biological means. The US Environmental Protection Agency (EPA) uses a slightly different definition for biocides as "a diverse group of poisonous substances including preservatives, insecticides, disinfectants, and pesticides used for the control of organisms that are harmful to human or animal health or that cause damage to natural or manufactured products". When compared, the two definitions roughly imply the same, although the US EPA definition includes plant protection products and some veterinary medicines. The terms "biocides" and "pesticides" are regularly interchanged, and often confused with "plant protection products". To clarify this, pesticides include both biocides and plant protection products, where the former regards substances for non food and feed purposes and the latter regards substances for food and feed purposes. When discussing biocides a distinction should be made between the biocidal active substance and the biocidal product. The biocidal active substances are mostly chemical compounds, but can also be microorganisms (e.g. bacteria). Biocidal products contain one or more biocidal active substances and may contain other non-active co-formulants that ensure the effectiveness as well as the desired pH, viscosity, colour, odour, etc. of the final product. Biocidal products are available on the market for use by professional and/or non-professional consumers. Although most of the biocidal active substances have a relative high toxicity; there are also examples of active substances with low toxicity, such as CO2, which exhibit their biocidal activity only under certain specific conditions such as in closed systems. In such cases, the biocidal product is the combination of the active substance and the device that ensures the intended biocidal activity, i.e. suffocation of rodents by CO2 in a closed system trap. Another example of biocidal products available to consumers are products impregnated with biocides (also called treated articles), such as clothes and wristbands impregnated with insecticides, socks impregnated with antibacterial substances etc. Biocides are commonly used in medicine, agriculture, forestry, and industry. Biocidal substances and products are also employed as anti-fouling agents or disinfectants under other circumstances: chlorine, for example, is used as a short-life biocide in industrial water treatment but as a disinfectant in swimming pools. Many biocides are synthetic, but there are naturally occurring biocides classified as natural biocides, derived from, e.g., bacteria and plants. A biocide can be: * A pesticide: this includes fungicides, herbicides, insecticides, algicides, molluscicides, miticides and rodenticides. * An antimicrobial: this includes germicides, antibiotics, antibacterials, antivirals, antifungals, antiprotozoals and antiparasites. See also spermicide. Biocide can also refer to the destruction of life, a form of omnicide that affects every living thing, not just humans; one who wishes that everything in the entire world, or universe, face extinction, is labeled a 'Biocidist', or having 'biocidal' ideologies. == Uses == In Europe the biocidal products are divided into different product types (PT), based on their intended use. These product types, 22 in total under the BPR, are grouped into four main groups, namely disinfectants, preservatives, pest control, and other biocidal products. For example, the main group "disinfectants" contains products to be used for human hygiene (PT 1) and veterinary hygiene (PT 3), main group "preservatives" contains wood preservatives (PT 8), the main group "for pest control" contains rodenticides (PT 14) and repellents and attractants (PT 19), while the main group "other biocidal products" contains antifouling products (PT 21). It should noted that one active substance can be used in several product types, such as for example sulfuryl fluoride, which is approved for use as a wood preservative (PT 8) as well as an insecticide (PT 18). Biocides can be added to other materials (typically liquids) to protect them against biological infestation and growth. For example, certain types of quaternary ammonium compounds (quats) are added to pool water or industrial water systems to act as an algicide, protecting the water from infestation and growth of algae. It is often impractical to store and use poisonous chlorine gas for water treatment, so alternative methods of adding chlorine are used. These include hypochlorite solutions, which gradually release chlorine into the water, and compounds like sodium dichloro-s-triazinetrione (dihydrate or anhydrous), sometimes referred to as "dichlor", and trichloro-s-triazinetrione, sometimes referred to as "trichlor". These compounds are stable while solids and may be used in powdered, granular, or tablet form. When added in small amounts to pool water or industrial water systems, the chlorine atoms hydrolyze from the rest of the molecule forming hypochlorous acid (HOCl) which acts as a general biocide killing germs, micro-organisms, algae, and so on. Halogenated hydantoin compounds are also used as biocides. An innovation is the use of copper and its alloys (brasses, bronzes, cupronickel, copper-nickel-zinc, and others) as biocidal surfaces to destroy a wide range of microorganisms (''E. coli'' O157:H7, methicillin-resistant ''Staphylococcus aureus'' (MRSA), ''Staphylococcus'', ''Clostridium difficile'', influenza A virus, adenovirus, and fungi). The United States Environmental Protection Agency has approved the registration of 355 different antimicrobial copper alloys that kill ''E. coli'' O157:H7, methicillin-resistant ''Staphylococcus aureus'' (MRSA), ''Staphylococcus'', ''Enterobacter aerogenes,'' and ''Pseudomonas aeruginosa'' in less than 2 hours of contact. As a public hygienic measure in addition to regular cleaning, antimicrobial copper alloys are being installed in healthcare facilities and in a subway transit system.〔http://construpages.com.ve/nl/noticia_nl.php?id_noticia=3032&language=en〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「biocide」の詳細全文を読む スポンサード リンク
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