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Published on: January 19, 2016
Methyl chloroform: impact on stratospheric ozone.
Science (New York, N.Y.)
|January 13, 1978
Summary
Regulations spurred methyl chloroform use, a substitute for trichloroethylene. Atmospheric release of methyl chloroform leads to significant ozone depletion, approximately 20% of that caused by chlorofluoromethanes.
Area of Science:
- Atmospheric Chemistry
- Environmental Science
- Ozone Layer Research
Background:
- Trichloroethylene regulations increased methyl chloroform usage.
- Methyl chloroform is a more photochemically inert solvent.
- Concerns exist regarding the atmospheric impact of solvent substitutes.
Purpose of the Study:
- To assess the potential for methyl chloroform to deplete stratospheric ozone.
- To quantify the ozone depletion potential of methyl chloroform relative to chlorofluoromethanes.
Main Methods:
- Utilized model calculations to simulate methyl chloroform's atmospheric transport.
- Analyzed past production and projected future release rates.
- Estimated steady-state ozone depletion based on atmospheric models.
Main Results:
- Approximately 15% of atmospheric methyl chloroform reaches the stratosphere.
- Methyl chloroform causes steady-state ozone depletion about 20% as large as 1973 chlorofluoromethane rates.
Conclusions:
- Methyl chloroform poses a significant threat to the stratospheric ozone layer.
- The use of methyl chloroform as a substitute warrants careful environmental consideration.
- Further research into ozone-depleting substances is crucial.
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