Dichloroacetic acid toxicity

Dichloroacetic acid is used in the synthesis of chloramphenicol [56-75-7] and aHantoin [97-59-6]. Dichloroacetic acid has vimcidal and fungicidal activity. It was found to be active against several staphylococci (36). The oral toxicity is low the LD q in rats is 4.48 g/kg. It can, however, cause caustic bums of the skin and eyes and the vapors are very irritating and injurious (28). 

Davis ME. 1992. Dichloroacetic acid and trichloroacetic acid increase ehloroform toxicity. J Toxicol Environ Health 37(1) 139-148. 

Following oral administration to animals, dichlorvos is rapidly absorbed from the digestive tract and extensively metabolized in the liver. The metabolism of dichlorvos has not been clearly elucidated because almost none of its potential metabolites has been yet unequivocally identified due mainly to its very rapid biotransformation rate (6). It appears, however, that the initial hydrolysis of dichlorvos, which occurs in all species, leads presumably to dichloroacetaldehyde (40), which is further metabolized by reduction to dichloroethanol or oxidation to dichloroacetic acid. In addition, dealkylation to desmethyldichlorvos appears to be another minor route of biotransformation, except in the mouse where desmethyldichlorvos constitutes at least 18% of the administered radioactivity. The metabolites of dichlorvos do not persist in tissues, whereas only trace levels occur in the milk of lactating mammals (41). There is no evidence tliat the metabolites of dichlorvos are toxic. 

Sodium chloroacetate is a reactive and toxic material, so it is hydrolyzed to glycolic acid nearly quantitatively at the end of the production cycle. Chloroacetic acid always contains traces of dichloroacetic acid, a toxic and unreactive material that appears on the California Prop. 65 list. The laws of the U.S. State of California require that the Governor of the State publish, annually, a list of chemicals known to cause cancer and reproductive abnormalities. This list is known by the ballot initiative that brought it into law as the Prop. 65 List . The vendors of surfactant betaines use grades of chloroacetic acid containing minimal amounts of dichloroacetic acid. 

Many chlorinated hydrocarbons are toxic to some degree. Thus the mixed solvent of dichloroacetic acid and ethylene dichloride should be handled with care. This solvent is also very corrosive. If it is necessary to prepare the PEG solutions, gloves should be worn. Use a pipette bulb do not pipette by mouth. Dispose of waste chemicals as instructed. 

DOT CLASSIFICATION 6.1 Label KEEP AWAY FROM FOOD SAFETY PROFILE Poisonous irritant to the skin, eyes, and mucous membranes. Hydrolyzes upon contact with moisture to form a product corrosive to tissue. See also DICHLOROACETIC ACID and ESTERS. Dangerous when heated to decomposition it emits highly toxic fumes of phosgene and... 

A great advantage of electrochemical reactions compared with chemical conversions is the effective contribution to pollution control. The direct electron transfer from the electrode to the substrate avoids the problem of separation and waste treatment of the frequently toxic end products of the chemical oxidants or reductants. Furthermore, by electrodialysis, organic acids or bases can be regenerated from their salts without the use of sulfuric acid or sodium hydroxide, for example, which lead to the coproduction of sodium salts or sulfates as waste [79]. At the same time, inorganic acids and bases, necessary for chemical production, are provided by this process. An application of electrodialysis has been demonstrated in the preparation of methoxyacetic acid by oxidation of methoxyethanol at the nickel hydroxide electrode [80]. Finally, unwanted side products can be converted into the wanted product, which increases the economy of the process and reduces the problem of waste separation and treatment. This is accomplished in the manufacture of chloroacetic acid by chlorination of acetic acid. There the side product dichloroacetic acid, formed by overchlorination, is cathodically converted to chloroacetic acid [81]. 

In search of less expensive, less toxic, and lower viscosity eluants, a few authors have proposed diluting the active ingredient with a common SEC eluant such as toluene, dichloromethane, or chloroform. To lower the operating temperature and minimize polymer degradation, mixtures of m-cresol with chlorobenzene (50 50, v/v, 43°C), dichloromethane (50 50, room temperature), and chloroform have been used, with 0.25 wt% benzoic acid added to prevent adsorption. In the same vein, o-chlorophenol has been diluted with chloroform (25 75) and used at 20°C. The main disadvantage in this latter solvent was a small dnidc for the polymer, which rendered refractive index measurements difficult. In addition, careful purification of the phenol is required to obtain a detection signal. Dichloroacetic acid diluted to 20 vol% with dichloromethane has been proposed as the mobile phase. However, even at this concentration, PA tends to degrade at room temperature. 

As discussed earlier, chloroform and dichloroacetic acid are formed as byproducts when drinking water is chlorinated (Section 8.9). In a study on laboratory rats, the co-administration of dichloroacetic acid and chloroform was found to greatly increase the liver toxicity of chloroform J23 ... 

Chloroform, dichloroacetic acid, and trichloroacetic acid are disinfection byproducts of water chlorination. In a study of laboratory rats it was shown that both dichloroacetic acid and trichloroacetic acid increase the renal toxicity of chloroform in test animals J10l... 

METHYL DICHLOROETHANOATE (116-54-1) C3H4CI2O2 Combustible, water-reactive liquid (flash point 176°F/80°C). Contact with water causes heat and decomposition to corrosive dichloroacetic acid. Aqueous solution is an acid. Incompatible with sulfuric acid, alkalis, ammonia, aliphatic amines, alkanolamines, alkylene oxides, amides, epichlorohydrin, organic anhydrides, isocyanates, vinyl acetate. Strong oxidizers may cause fire and explosions. Attacks metals in the presence of moisture. Thermal decomposition releases toxic phosgene and HCl gases. 

Applicators and residents of dichlorvos (DDVP) treated structures were monitored for evidence of insecticide exposure using exposure pads, air samplers, serum and red blood cell acetylcholinesterase (AChE) tests, and urine analysis. There was no evidence of DDVP or dichloroacetic acid (DCAA) in the urine of applicators or cooperators. There were slight but significant differences (Pi0.05) in serum AChE activity of residents of treated units, but erythrocyte AChE was unchanged. Applicator AChE test results were inconclusive. It was concluded that there was not a significant risk. In terms of acute toxicity, to either the pesticide applicators or the residents of treated structures. 

The toxieity of triehloroethylene is dependent upon metabolism and induction of cytochrome P450. Triehloroethylene is metabolized through chloral hydrate to compounds including trichloroacetic acid and dichloroacetic acid which alter intercellular communication, induce peroxisome proliferation and may promote tumor production. Significant variability in trichloroethylene metabolism in 23 human haptic microsomal samples was reported by Lipscomb et al. It was also demonstrated that the trichloroethylene metabolism is dependent on enzymatic activities of the cytochrome system, and they conclude that their data indicates that humans are not uniform in their capacity for CPY dependent metabolism of trichloroethylene and increased activity may increase susceptibility to trichloroethylene induced toxicity in humans. These observations are compatible with the variability reaction which is depending on nutritional factors, enzyme induction factors, hormonal factors and interaction with other environmental chemicals, prescription medications and general health conditions, and explains the variable reports as far as trichloroethylene and level of liver toxicity in the various individuals studied. 

Chloroacetic acid and the dichloroacetic acid present in the reagent used in small amounts are both unwanted by-products in betaines (as well as in other zwitterionic or amphoteric surfactants such as amphoglycinates) because of their toxicity. Chloroacetic acid is almost completely depleted during the carboxymethylation reaction, but it is almost inert under the typical reaction conditions. By submitting betaines to additional posttreatment steps, the residual chloroacetic acids can be reduced. This can be achieved either by reacting at alkaline pH or by additional treatment with ammonia or amino acids that reduces the amount of monochloroacetic acid [27]. 

Typical solvents include inorganic salt solutions, and dissolution is achieved with the aid of mechanical energy [138]. Halogenated solvent systems, including solvents such as trichloroacetic acid (TCA) and dichloroacetic acid (DCA), have been extensively studied by many researchers, but their use is problematic because TCA, DCA and similar solvents are either corrosive, environmentally harmful or toxic [138]. Other solvent systems proposed include amide-LiCl systems, such as DMAc/LiCl, and amine oxide/water system, such as NMMO/H2O. A detailed discussion of solvent systems for chitin and wet-spinning of chitin was given by Kumar [138,139]. 

Mather GG, Exon JH, Roller LD Subchronic 90 day toxicity of dichloroacetic and trichloroacetic acid in rats. Toxicology 64 71-80, 1990... 

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