Abstract
Two trips were made from Montreal, Que., to London, England, in June and August, 1951, and samples of bacteria and fungi were obtained throughout the flight using quantitative and qualitative methods. Three sampling methods were used, employing the McGill G.E. and slit samplers and a filter. Plates were used, supplemented by silicone slides in the slit sampler. Bacteria varied from 0.0 to 0.05 per cu. ft. in polar air and 0.03-0.9 per cu. ft. for tropical air over the ocean in June. Fungi in polar air ranged from 0.1 to 0.9 per cu. ft. and from 0.2 to 9.0 per cu. ft. in tropical air in June. There was very little difference in the June, and August flights as far as viable organisms were concerned. Fungus spores showed striking differences in air masses. Polar air over the ocean had a maximum of 3.9 per cu. ft. in August whereas tropical air had a maximum of 15.1 per cu. ft. in June. Over land in August a maximum of 361.4 fungus spores per cu. ft. was obtained in tropical air over eastern Canada. Cladosporium was the commonest fungus, with Alternaria, Pullularia, yeasts, Penicillium, Botrytis, and Stemphylium most numerous among 27 types. Of the 4991 colonies the above occurred as 82.3, 2.6, 2.3, 2.1, 1.6, 1.5, and 1.1% of the total. Micrococci, Sarcina, Gram negative rods, Gram positive pleomorphic rods, and aerobic sporeformers occurred as 41.4, 4.3, 20.4, and 33.2% in June and 13.2, 20.7, 37.0, and 29.0% of the total in August.
Publisher
Canadian Science Publishing