[Alive microorganism in the workplace ambient air in plants disposing communal waste]

This paper presents the results of the identification and determination of alive microorganisms in the air samples collected from the breath zone of workers employed in the waste collection and disposal. Samples were taken during waste collection and in the waste reloading, sorting and composting plants. In addition, samples were taken at stationary sites: in the city and inside flats. Different kinds of species of Gram-positive bacteria (Micrococcus, Staphylococcus, Enterococcus, Bacillus, Listeria, Corynebacterium, Rhodococcus) and Gram-negative rods (Enterobacteriaceae, Pseudomonas and other aerobic bacteria) were found. On every work site, there were fecal bacteria (Escherichia coli, Enterococcus faecalis and Enterococcus faecium). The city areas and flats were free from this kind of bacteria. The number of mesophilic bacteria and thread-like fungi exceeding 10(4) cfu/m3 of air was counted on every work site. The largest number of mesophilic bacteria and Actinomycetes were found in the waste composting plant (10(4)-10(6) and 10(3)-10(5) cfu/m3, respectively), whereas the majority of fungal spores were counted during waste collection and sorting. (10(4)-10(5) cfu/m3). On the city streets there were no Actinomycetes and the number of fungal spores (10(4)/m3 of air) was similar to that observed in the waste reloading and composting plants. The amount of mesophilic bacteria in the city and flat samples was below 10(2)-10(3) cfu/m3. As to the number of fungal spores and Actinomycetes there was a limit of determination (10(1)-10(2) cfu/m3). The majority of mesopholic bacteria identified in the air were classified as the second group of occupational risk in the Council Directive 54/2000/EU. Bearing in mind that Gram-negative rods (especially intestinal) were identified in all samples, it is suggested to use endotoxin concentration as one of possible criteria for assessing the hygiene conditions at workplaces.