1.1.2- Trichloroethane toxicity

The kidney does not appear to be a target organ for 1,1,1-trichloroethane toxicity. The highest NOAEL values and all reliable LOAEL values for renal effects in each species and duration category are recorded in Table 2-1 and plotted in Figure 2-1. 

AH volatile organic solvents are toxic to some degree. Excessive vapor inhalation of the volatile chloriaated solveats, and the central nervous system depression that results, is the greatest hazard for iadustrial use of these solvents. Proper protective equipment and operating procedures permit safe use of solvents such as methylene chloride, 1,1,1-trichloroethane, trichloroethylene, and tetrachloroethylene ia both cold and hot metal-cleaning operations. The toxicity of a solvent cannot be predicted from its chlorine content or chemical stmcture. For example, 1,1,1-trichloroethane is one of the least toxic metal-cleaning solvents and has a recommended threshold limit value (TLV) of 350 ppm. However, the 1,1,2-trichloroethane isomer is one of the more toxic chloriaated hydrocarboas, with a TLV of only 10 ppm. 

Inhibited grades of 1,1,1-trichloroethane are used in hundreds of different industrial cleaning appHcations. 1,1,1-Trichloroethane is preferred over trichloroethylene or tetrachloroethylene because of its lower toxicity. Additional advantages of 1,1,1-trichloroethane include optimum solvency, good evaporation rate, and no fire or flash point as determined by standard test methods. Common uses include cleaning of electrical equipment, motors, electronic components and instmments, missile hardware, paint masks, photographic film, printed ckcuit boards, and various metal and certain plastic components during manufacture (see Metal surface treatments). 

Trichloroethane is much more toxic than 1,1,2-trichloroethane in acute exposure studies (108). The 1991 ACGIH recommended TWA value for... 

An acute lethal dose (LC q) for vapor exposure to 1,1,2-trichloroethane in the rat is 2000 ppm for a 4-h exposure. The same lethal effect occurs at 18,000 ppm vapor during 3 h exposure to 1,1,1-trichloroethane. The oral LD q for 1,1,2-trichloroethane in rats is 0.1—0.2 g/kg, classifying it as moderately toxic (109). Liver and kidney damage occurs at even lower dosages. Skin adsorption is a possible route of overexposure. 

NOTE - Petrochemical plants also generate significant amounts of solid wastes and sludges, some of which may be considered hazardous because of the presence of toxic organics and heavy metals. Spent caustic and other hazardous wastes may be generated in significant quantities examples are distillation residues associated with units handling acetaldehyde, acetonitrile, benzyl chloride, carbon tetrachloride, cumene, phthallic anhydride, nitrobenzene, methyl ethyl pyridine, toluene diisocyanate, trichloroethane, trichloroethylene, perchloro-ethylene, aniline, chlorobenzenes, dimethyl hydrazine, ethylene dibromide, toluenediamine, epichlorohydrin, ethyl chloride, ethylene dichloride, and vinyl chloride. 

The oxidation of a number of chloroalkanes and chloroalkenes including dichlorometh-ane, chloroform, 1,1,2-trichloroethane, and 1,2,2-trichloroethene (Vannelli et al. 1990). Although the rate of cometabolism of trihalomethanes increased with levels of bromine substitution so also did toxicity. Both factors must therefore be evaluated in the possible application of this strain (Wahman et al. 2005). 

The purpose of this work was to determine the toxicity to mosquito larvae of insecticide spray residues. That certain insecticides are translocated in plants (4, 5) adds impetus to this study. Fresh orchard fruit sprayed or dusted with preparations containing parathion (0,0-diethyl O-p-nitrophenyl thiophosphate), tetraethyl pyrophosphate (TEPP, HEPP), DDD [2,2-bis(p-chlorophenyl)-l,l-dichloroethane], DDT [2,2-bis(p-chlorophenyl)-l,l,l-trichloroethane], chlorinated camphene, and basic lead arsenate were shipped from California to Yonkers, N. Y., by air express for bioassay. 

Ozone depleters (e.g. CFCs, 1,1,1-trichloroethane) Least acceptable Toxic and carcinogenic solvents (CCI4, benzene)... 

Alexander, H.C., McCarty, W.M., and Bartlett, E.A. Toxicity of perchloroethylene, trichloroethylene, 1,1,1-trichloroethane, and methylene chloride to fathead minnows, Bull. Environ. Contam. Toxicol, 20(3) 344-352, 1978. 

In addition to the conventional pollutant constituents, USEPA made a survey of the presence of the 126 toxic pollutants listed as priority pollutants in refinery operations in 1977 [5]. The survey responses indicated that 71 toxic pollutants were purchased as raw or intermediate materials 19 of these were purchased by single refineries. At least 10% of aU refineries purchase the following toxic pollutants benzene, carbon tetrachloride, 1,1,1-trichloroethane, phenol, toluene, zinc and its compounds, chromium and its compounds, copper and its compounds, and lead and its compounds. Zinc and chromium are purchased by 28% of all refineries, and lead is purchased by nearly 48% of all plants. 

Wahlberg JE Percutaneous toxicity of solvents. A comparative investigation in the guinea pig with benzene, toluene, and 1,1,2-trichloroethane. Ann Occup Hyg 19 226-229, 1976... 

The toxicity of 1,1,1-trichloroethane has been reviewed (WHO, 1992 Agency for Toxic Substances and Disease Registry, 1995). 

When female Long-Evans rats were exposed to 1,1,1-trichloroethane by inhalation (11 470 1100 mg/m3 for 6 h per day) for two weeks before mating and through day 20 of gestation (York et al., 1982), no maternal toxicity was observed, and the only sign of... 

Trichloroethane is neurotoxic and hepatotoxic, following exceptionally high exposure concentrations of people and also in rodents. No structural damage has been reported in reproductive toxicity studies in rats and mice, but delayed development, particularly of neurological attributes, has been reported in one study with mice. 

Quasi, J.E, Calhoun, L.L. Frauson, L.E. (1988) 1,1,1-Trichloroethane formulation a chronic inhalation toxicity and oncogenicity study in Fischer 344 rats and B6C3F1 mice. Fundam. appl. Toxicol.. 11.611-625... 

Takahara, K. (1986) Experimental study on toxicity of trichloroethane. I. Organ distribution of... 

---