The purpose of examinations was defined role of environment of school in interindyvidual transmisions. The yeast and yeast - like fungi isolated from the oral cavity, troat and nose from 270 healthy children, at the age of 6 to 15 years, from country and municipal schools. The frequency of occurrence of fungi in country was higher than in minicipal schools by the resambling biodifferentiation. Totally 13 species belonging to 5 genera were detected in the examined material: Candida, Rhodotorula, Saccharomyces, Saccharomycopsis i Trichosporon. Increasing part of S. capsularis was noted in ontocenoses of healthy children. The qualitative and quantitative changes testify about changes of environment. Simultaneously, they inform about timely condition of mycoflora of the examined ontocenosis and surroundings.
The content of nitrates and nitrites in the Polish foodstuffs varies to a great extent. The highest levels have been noted in vegetables. Spinach, radish, lettuce, parsley, carrot, celery, beets, cabbage and potatoes belong to these vegetables which assimilate a high content of nitrates. It has been stated that the admissible daily level of nitrates and nitrites has been exceeded in the daily food rations in various groups of population. That is why the elaboration of the suitable instructions for the vegetable producers and a systematic control of the content of toxic compounds are urgently needed.