Carcinogenic chlorinated hydrocarbons

Many landfills contain VOCs (volatile organic chemicals). This group of chemicals includes benzene and toluene (both carcinogens), chlorinated hydrocarbons, such as carbon tetrachloride, and trichloroethylene, which previously was used as a dry-cleaning solvent. Even though these compounds are not very soluble in water, they do accumulate at the parts-per-million level. Their long-term effect on human health is unknown at this time. 

Liver cancer can also be a consequence of exposure to hepatotoxic chemicals. Natural hepatocarcinogens include fungal aflatoxins. Synthetic hepato-carcinogens include nitrosoamines, certain chlorinated hydrocarbons, polychlorinated biphenyls (PCBs), chloroform, carbon tetrachloride, dimethyl-benzanthracene, and vinyl chloride.Table 5.15 lists the chemical compounds that induce liver cancer or cirrhosis in experimental animals or... 

Evidence that many of these compounds can have adverse effects on the immune, endocrine and nervous systems and that some are carcinogenic has grown during the last decade. The role of chlorofluorocarbons (CFCs) and of methyl bromide in the ozone layer depletion is well established (ref. 3).It is therefore not surprising that many halogenated derivatives are cast as environmental and health villains by various concerned groups who call for total phase out of chlorine and chlorinated hydrocarbons. 

Goldsworthy TL, Popp JA. 1987. Chlorinated hydrocarbon-induced peroxisomal enzyme activity in relation to species and organ carcinogenicity. Toxicol Appl Pharmacol 88 225-233. 

This includes bioremediation cases of contaminated sites with several toxic and carcinogenic pollutants, such as petroleum hydrocarbons, PAHs, dichlorobenzene, chlorinated hydrocarbons, carbon tetrachloride, Dicamba, methyl bromide, trinitrotoluene, silicon-based organic compounds, dioxins, alkyl-phenol polyethoxylates, nonylphenol ethoxylates, and polychlorinated biphenyls. The following is a brief summary of each case. 

Ethylene dichloride is a colorless liquid with a bp of 84°C. As with many chlorinated hydrocarbons, it is quite toxic and has a TLV value of 10 ppm (TWA). It is on the list of Reasonably Anticipated to Be Human Carcinogens. ... 

Methylene chloride is used in refrigeration, aerosol propellants, paint stripping, urethane foam-blowing agents, adhesive, and food extractants. It has low toxicity compared with other chlorinated hydrocarbons and has been show n lo be neither mutagenic nor carcinogenic toward humans. 

Under hypoxic conditions, 1,1-dichloroethane gives rise to free radicals. However, its ability to develop free radicals is much less when compared to other chlorinated hydrocarbons like trichloroethane and carbon tetrachloride. It has been suggested that these free radicals possess the potential to induce toxic and carcinogenic effects. There is no correlation between the ease of free radical activation, covalent binding formation, or carcinogenic potency (Tomasi et al. 1984)... 

DFG MAK Confirmed Human Carcinogen DOT CLASSIFICATION 6.1 Label Poison SAFETY PROFILE Confirmed carcinogen with experimental carcinogenic and neoplastigenic data. Poison by inhalation. Moderately toxic by ingestion. A strong irritant and lachrymator. Causes central nervous system depression. Mutation data reported. When heated to decomposition it emits toxic fumes of Cl". See also CHLORINATED HYDROCARBONS, AROMATIC. 

SAFETY PROFILE Narcotic in high concentrations. Questionable carcinogen with experimental neoplastigenic data. See also BROMIDES and CHLORINATED HYDROCARBONS, ALIPHATIC. Flammable liquid. Dangerous fire hazard when exposed to heat or flame. When heated to decomposition it emits toxic fumes of Br" can react with oxidizing materials. To fight fire, use water, spray or mist, foam, CO2, dry chemical. 

SAFETY PROFILE Poison by intravenous route. Questionable carcinogen with experimental neoplastigenic data. Mutation data reported. When heated to decomposition it emits toxic Cl". See also CHLORINATED HYDROCARBONS, AROMATIC. 

DFG MAK Confirmed Animal Carcinogen, Suspected Human Carcinogen SAFETY PROFILE Confirmed carcinogen. Poison by ingestion. Moderately toxic by inhalation and skin contact. Experimental reproductive effects. A skin and severe eye irritant. Mutation data reported. Moderately flammable by heat, flames (sparks), or powerful oxidizers. See also v LLYL COMPOUNDS and CHLORINATED HYDROCARBONS, ALIPHATIC. When heated to decomposition it yields highly toxic Cr. To fight fire, use water (as a blanket), spray, mist, dry chemical. 

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