|Document ID (ISN)||53197|
|ISSN - Serial title
||0355-3140 - Scandinavian Journal of Work, Environment and Health
|Convention or series no.
||Karlsson K., Malmberg P.
||Characterization of exposure to molds and actinomycetes in agricultural dust by scanning electron microscopy, fluorescence microscopy and the culture method
||Oct. 1989, Vol.15, No.5, p.353-359. Illus. 21 ref.
||Air samples from 79 farms with 105 to 1011 microorganisms/m3 were analysed by scanning electron microscopy (SEM), fluorescence microscopy (FM) and the culture method. The total concentration of microorganisms (particularly actinomycetes) was underestimated when assessed as colony-forming units (cfu). The average cfu count was one-sixth of the total count according to SEM or FM, and there was considerable individual variability. This finding can be partly explained by the aggregation of spores. Single spores accounted for 2-65% of all spores in 35 samples. There was an average of three spores/particle, and 93 (range 67-100) % of the spores were single or in aggregates of respirable size. Aggregation was more pronounced for actinomycetes and at high spore counts. Actinomycetes and bacteria could not be distinguished by FM. Bacteria (other than actinomycetes) were not detected by SEM, yet the total count of microorganisms was similar for FM and SEM. Most particles were spores from actinomycetes and fungi of the genera Aspergillus or Pencillium.
||moulds; microorganisms; atmospheric pollution; agricultural operations; organic dust
||spores; bacteria; sample processing; electron microscopy; exposure evaluation
||D - Periodical articles
||Dust, aerosols and related diseases
|Broad subject area(s)