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Pesticides are substances meant for attracting, seducing, and then destroying, or mitigating any pest.〔US Environmental (July 24, 2007), (What is a pesticide? ) epa.gov. Retrieved on September 15, 2007.〕 They are a class of biocide. The most common use of pesticides is as plant protection products (also known as crop protection products), which in general protect plants from damaging influences such as weeds, fungi, or insects. This use of pesticides is so common that the term ''pesticide'' is often treated as synonymous with ''plant protection product'', although it is in fact a broader term, as pesticides are also used for non-agricultural purposes. The term pesticide includes all of the following: herbicide, insecticide, insect growth regulator, nematicide, termiticide, molluscicide, piscicide, avicide, rodenticide, predacide, bactericide, insect repellent, animal repellent, antimicrobial, fungicide, disinfectant (antimicrobial), and sanitizer.〔Carolyn Randall (ed.), et al., (''National Pesticide Applicator Certification Core Manual'' ) (2013) (National Association of State Departments of Agriculture ) Research Foundation, Washington, DC, Ch.1〕 In general, a pesticide is a chemical or biological agent (such as a virus, bacterium, antimicrobial, or disinfectant) that deters, incapacitates, kills, or otherwise discourages pests. Target pests can include insects, plant pathogens, weeds, mollusks, birds, mammals, fish, nematodes (roundworms), and microbes that destroy property, cause nuisance, or spread disease, or are disease vectors. Although pesticides have benefits, some also have drawbacks, such as potential toxicity to humans and other species. According to the Stockholm Convention on Persistent Organic Pollutants, 9 of the 12 most dangerous and persistent organic chemicals are organochlorine pesticides.〔(Beginner's guide )〕 ==Definition== The Food and Agriculture Organization (FAO) has defined ''pesticide'' as: :any substance or mixture of substances intended for preventing, destroying, or controlling any pest, including vectors of human or animal disease, unwanted species of plants or animals, causing harm during or otherwise interfering with the production, processing, storage, transport, or marketing of food, agricultural commodities, wood and wood products or animal feedstuffs, or substances that may be administered to animals for the control of insects, arachnids, or other pests in or on their bodies. The term includes substances intended for use as a plant growth regulator, defoliant, desiccant, or agent for thinning fruit or preventing the premature fall of fruit. Also used as substances applied to crops either before or after harvest to protect the commodity from deterioration during storage and transport.〔 Pesticides can be classified by target organism (e.g., herbicides, insecticides, fungicides, rodenticides, and pediculicides〔〔(【引用サイトリンク】title=www.chromatography-online.org )〕 - see table), chemical structure (e.g., organic, inorganic, synthetic, or biological (biopesticide),〔Council on Scientific Affairs, American Medical Association. (1997). (Educational and Informational Strategies to Reduce Pesticide Risks ). Preventive Medicine, Volume 26, Number 2〕 although the distinction can sometimes blur), and physical state (e.g. gaseous (fumigant)).〔 Biopesticides include microbial pesticides and biochemical pesticides.〔EPA. (Types of Pesticides ). Last updated on Thursday, January 29th, 2009.〕 Plant-derived pesticides, or "botanicals", have been developing quickly. These include the pyrethroids, rotenoids, nicotinoids, and a fourth group that includes strychnine and scilliroside.〔Kamrin MA. (1997). ''Pesticide Profiles: toxicity, environmental impact, and fate.'' CRC Press.〕 Many pesticides can be grouped into chemical families. Prominent insecticide families include organochlorines, organophosphates, and carbamates. Organochlorine hydrocarbons (e.g., DDT) could be separated into dichlorodiphenylethanes, cyclodiene compounds, and other related compounds. They operate by disrupting the sodium/potassium balance of the nerve fiber, forcing the nerve to transmit continuously. Their toxicities vary greatly, but they have been phased out because of their persistence and potential to bioaccumulate.〔 Organophosphate and carbamates largely replaced organochlorines. Both operate through inhibiting the enzyme acetylcholinesterase, allowing acetylcholine to transfer nerve impulses indefinitely and causing a variety of symptoms such as weakness or paralysis. Organophosphates are quite toxic to vertebrates, and have in some cases been replaced by less toxic carbamates.〔 Thiocarbamate and dithiocarbamates are subclasses of carbamates. Prominent families of herbicides include phenoxy and benzoic acid herbicides (e.g. 2,4-D), triazines (e.g., atrazine), ureas (e.g., diuron), and Chloroacetanilides (e.g., alachlor). Phenoxy compounds tend to selectively kill broad-leaf weeds rather than grasses. The phenoxy and benzoic acid herbicides function similar to plant growth hormones, and grow cells without normal cell division, crushing the plant's nutrient transport system.〔 Triazines interfere with photosynthesis.〔 Many commonly used pesticides are not included in these families, including glyphosate. Pesticides can be classified based upon their biological mechanism function or application method. Most pesticides work by poisoning pests.〔Cornell University. (Toxicity of pesticides ). Pesticide fact sheets and tutorial, module 4. Pesticide Safety Education Program. Retrieved on 2007-10-10.〕 A systemic pesticide moves inside a plant following absorption by the plant. With insecticides and most fungicides, this movement is usually upward (through the xylem) and outward. Increased efficiency may be a result. Systemic insecticides, which poison pollen and nectar in the flowers, may kill bees and other needed pollinators. In 2009, the development of a new class of fungicides called paldoxins was announced. These work by taking advantage of natural defense chemicals released by plants called phytoalexins, which fungi then detoxify using enzymes. The paldoxins inhibit the fungi's detoxification enzymes. They are believed to be safer and greener.〔EurekAlert. (2009). (New 'green' pesticides are first to exploit plant defenses in battle of the fungi ).〕 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「Pesticide」の詳細全文を読む スポンサード リンク
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