Physiological Response Attending Exposure to Vapors of Methyl Bromide, Methyl Chloride, Ethyl Bromide and Ethyl Chloride Prepared from Data Contained in the Report of the Bureau of Mines to the National Research Council and the Dow Chemical Company.

Extension of mechanical refrigeration in the home, in public buildings, in industry and in hot mines has prompted this study of refrigerants in terms of fire, explosive, health and general safety hazards. Inhalation experiments with guinea-pigs as test animals were conducted. The work was planned to provide information as to the acute effects arising from high and low concentrations of these gases in air. The bromine compounds were included because of their high fire repelling qualities, which might lead to admixtures with refrigerants of known flammability. From these experiments, results have accrued that arrange these compounds in an order of increasing toxicity as follows: ethyl chloride, methyl chloride, ethyl bromide and methyl bromide. This order is somewhat altered for long exposures to slight concentrations. The symptoms produced by methyl chloride, methyl bromide and ethyl bromide were similar. For exposure to high concentrations of vapors the symptoms were chiefly of an