Chlorophenols: Phenols substituted with one or more chlorine atoms in any position.Pentachlorophenol: An insecticide and herbicide that has also been used as a wood preservative. Pentachlorphenol is a widespread environmental pollutant. Both chronic and acute pentachlorophenol poisoning are medical concerns. The range of its biological actions is still being actively explored, but it is clearly a potent enzyme inhibitor and has been used as such as an experimental tool.2,4,5-Trichlorophenoxyacetic Acid: An herbicide with strong irritant properties. Use of this compound on rice fields, orchards, sugarcane, rangeland, and other noncrop sites was terminated by the EPA in 1985. (From Merck Index, 11th ed)2-Methyl-4-chlorophenoxyacetic Acid: A powerful herbicide used as a selective weed killer.Glycolates: Derivatives of ACETIC ACID which contain an hydroxy group attached to the methyl carbon.Herbicides: Pesticides used to destroy unwanted vegetation, especially various types of weeds, grasses (POACEAE), and woody plants. Some plants develop HERBICIDE RESISTANCE.Desulfitobacterium: A genus of anaerobic, gram-positive bacteria in the family Peptococcaceae, that reductively dechlorinates CHLOROPHENOLS.Dioxins: Chlorinated hydrocarbons containing heteroatoms that are present as contaminants of herbicides. Dioxins are carcinogenic, teratogenic, and mutagenic. They have been banned from use by the FDA.Chlorobenzoates: Benzoic acid or benzoic acid esters substituted with one or more chlorine atoms.Biodegradation, Environmental: Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.Fungicides, Industrial: Chemicals that kill or inhibit the growth of fungi in agricultural applications, on wood, plastics, or other materials, in swimming pools, etc.Cyclodextrins: A homologous group of cyclic GLUCANS consisting of alpha-1,4 bound glucose units obtained by the action of cyclodextrin glucanotransferase on starch or similar substrates. The enzyme is produced by certain species of Bacillus. Cyclodextrins form inclusion complexes with a wide variety of substances.Water Purification: Any of several processes in which undesirable impurities in water are removed or neutralized; for example, chlorination, filtration, primary treatment, ion exchange, and distillation. It includes treatment of WASTE WATER to provide potable and hygienic water in a controlled or closed environment as well as provision of public drinking water supplies.Water Pollutants, Chemical: Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.beta-Cyclodextrins: Cyclic GLUCANS consisting of seven (7) glucopyranose units linked by 1,4-glycosidic bonds.