Collection of airborne micro‐organisms on Nuclepore filters, estimation and analysis—CAMNEA method

Abstract

The total number of airborne micro-organisms collected on Nuclepore filters was determined by acridine orange staining and epifluorescence microscopy. The viable fraction of the total numbers varied significantly when actinomycete and fungal spores from different environments were stored on the filter surface for 1 week, although the microflora composition was not altered. A high correlation between viable and total counts was noted in environments where the airborne flora was dominated by fungal spores, while a low correlation was found for airborne bacteria. Peak values of the total counts registered in some work environments varied between 10(7) and 10(11) micro-organisms/m3. Size analysis showed a dominating fraction of respirable micro-organisms (aerodynamical diameter less than 5 micron). The investigation shows that it is of the utmost importance to combine viable counts with total count enumeration in the study of exposure to micro-organisms in work-related situations.

Farmers’ exposure to dusts and gases in modern Finnish cubicle cow houses

“…The concentrations of viable airborne fungi and actinomycetes measured were at the order of lO'-lO 3 cfu/m 3 which is lower than those in previous Finnish studies (Kotimaa et al 1984, Pasanen et al 1989, Hanhela et al 1995. The concentrations of different microbes were higher, but not in all cases significantly higher, during milking than before work or 2 hours after work.…”

“…These results may be due to modern farm practices in which there is little use of hay for feed, little use of straw for bedding, or no bedding at all. The worst sources of airborne spores are thus eliminated or their role is clearly lessened (Pasanen et al 1989, Kotimaa 1990, Kotimaa et ai. 1991, Dalphin et ai.…”

“…Three types of samples were taken, one background sample one hour before work, one during milking when hay, forage and fodder grain were also delivered to cows and heifers, and the third one two hours after the work was finished. The concentrations of total spores were determinedby the CAM-NEA method described by Palmgren et al (1986).…”

Association between Use of Synthetic Metalworking Fluid and Risk of Developing Rhinitis‐related Symptoms in an Automotive Ring Manufacturing Plant

“…The collected aerosol was resuspended in 10 mL sterile, nonpyrogenic water by orbital shaking (1,000 RPM for 15 min) at room temperature, and endotoxin concentrations were quantified using the Kinetic Turbidimetric Limulus Amoebocyte Lysate method (Pyrogent-5000, BioWhittaker, Walkersville, MD) of the American Society for Testing and Materials (E2144-01) 18) . Airborne microorganisms such as viable bacteria and fungi were collected and analyzed using the CAMNEA method, as recommended by Palmgren et al 19) We were not able to directly input exposure to MWFs and biological agents into the logistic regression models, but levels of exposure are compared with results reported from automobile plants using MWF and discussed with regard to their possible role in causing nasal symptoms.…”

Optimizing the Recovery of Surrogates for Bacterial Bioterrorism Agents from Ventilation Filters

“…Capillary pore membrane filters have been utilized for sampling and recovery of bacterial aerosols [15,16]. Gelatin filters have been used effectively for sampling airborne bacteria with subsequent digestion of the filters for quantitative analyses of the microorganisms [17].…”