1981 Volume 16 Issue 1 Pages 1-11
Atmospheric halocarbons were collected by means of the dryfreeze trapping method in the altitude range from 8700m to 11100m over Northern Pacific Ocean and Northern American Area using a jet air liner, Boeing 747 cargoplane, flying from Tokyo to New York via Anchorage in March 1980. “Bleed air” from the compressors of jet engines was passed through the trap tubing, packed with the porous polymer PORAPAK Q, which was cooled at a temperature of dry ice, -78°C. Collected air samples were analysed by Electron Capture Gas Chromatography and Gas Chromatograph-Mass Spectrometry.
The materials determined at our laboratory were F-11 (CCI3F), F-12 (CCI2F2), CCI4, CHCI3, C2H3CI3, C2CI4 and also C2HCI3.
The sample collection system used here was very compact in volume and made operations safe, so that it was quite suitable for the work on a aircraft in which there are many limitations.
Comparing the results with other reports, concentrations of F-11, F-12 and CCI4 are lower than those of European reports.
And the concentrations of other chlorocarbons, except trichloroethane, might be athigh level although there are few report to be compared.
