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ectrum Laboratories : Chemical Fact Sheet-C #75694 htt- •//www.speclab.com/compound/c75694.htm u `/ Boiling Point 23.7 DEG C @ 760 MM HG Melting Point -111 DEG C Molecular [137.38 Weight Density 1.494 @ 17.2 DEG C/4 DEG C LIQUID Odor Threshold Low:28.0 mg/cu m;High: 1170.4 mg/cu m Concentration Sensitivi Ilmmediately irritating to the eye. Trichlorofluoromethane(Freon 11)was primarily released to the environment during its use as a propellant in aerosol sprays. However,this use was banned in the US on Dec. 15, 1978. Other sources of emissions include its use as a refrigerant,foaming agent for polyurethane foams, solvent and degreaser,and fire extinguishing agent. If released in water or on land, trichlorofluoromethane will be lost by volatilization(half-life 6.1 hr in a typical river). Concentration profiles in oceans show that trichlorofluoromethane is primarily in surface layers, suggesting that the oceans are not a sink for this chemical.Bioconcentration in fish is unlikely.If released on land, Environmental trichlorofluoromethane may also pass through the soil,where it is likely to persist for long periods Impact of time.The troposphere is apparently also not a sink for trichlorofluoromethane since estimates of its half-life range from 52 to 207 years. In fact the only major sink for trichlorofluoromethane is its slow diffusion into the stratosphere where photolysis occurs and subsequent reactions which destroy ozone.As a result of its stability, trichlorofluoromethane is transported long distances and its concentration is fairly uniform around the globe away from known sources. Since there are no major tropospheric sinks,the concentration of trichlorofluoromethane had been increasing by about 10%a year in the late 1970's,a trend that seems to be leveling off as a result of its ban in aerosols. Human exposure is occupational from ambient air although drinking TERRESTRIAL FATE: If released on soil,trichlorofluoromethane will rapidly evaporate into the atmosphere because of its high vapor pressure as well as readily pass through soil because of its negligible adsorption to soil.AQUATIC FATE: If released into water,trichlorofluoromethane will be lost almost exclusively by evaporation(half-life 6.1 hr in a typical river).Abiotic degradation, biodegradation,and adsorption to sediment will be insignificant.ATMOSPHERIC FATE: Environmental Trichlorofluoromethane is very stable in the troposphere having a half-life of 52-207 years. It is Fate transported long distances,being found even at the South Pole. Some trichlorofluoromethane will be lost due to rainout but will return to the atmosphere as a result of evaporation.The only degradation loss process is through diffusion to the stratosphere where photolysis occurs.As a result of this latter process,ozone is destroyed.The sharp decrease in trichlorofluoromethane concentration above the tropopause supports this conclusion.ATMOSPHERIC FATE:THEIR USE FOR AEROSOL SPRAYS WAS PROHIBITED BECAUSE OF THEIR DEPLETING EFFECT ON STRATOSPHERIC OZONE. /CHLOROFLUOROCARBONS v 2 of 3 1/5/99 3:28 PM