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Assessment of human exposure to airborne fungi in agricultural confinements: personal inhalable sampling versus stationary sampling

100%

Adhikari A., Reponen T., Lee S. A., Grinshpun S. A.

Annals of Agricultural and Environmental Medicine

2004

tom 11

nr 2

Accurate exposure assessment to airborne fungi in agricultural environments is essential for estimating the associated occupational health hazards of workers. The objective of this pilot study was to compare personal and stationary sampling for assessing farmers' exposure to airborne fungi in 3 different agricultural confinements located in Ohio, USA (hog farm, dairy farm, and grain farm), using Button Personal Inhalable Samplers. Personal exposures were measured with samplers worn by 3 subjects (each carrying 2 samplers) during 3 types of activities, including animal feeding in the hog farm, cleaning and animal handling in the dairy farm, and soybean unloading and handling in the grain farm. Simultaneously, the stationary measurements were performed using 5 static Button Samplers and 1 revolving Button Sampler. The study showed that the total concentration of airborne fungi ranged from 1.4 × 104-1.2 × 105 spores m-3 in 3 confinements. Grain unloading and handling activity generated highest concentrations of airborne fungi compared to the other 2 activities. Prevalent airborne fungi belonged to Cladosporium, Aspergillus/Penicillium, Ascospores, smut spores, Epicoccum, Alternaria, and Basidiospores. Lower coefficients of variations were observed for the fungal concentrations measured by personal samplers (7-12%) compared to the concentrations measured by stationary samplers (27-37%). No statistically significant difference was observed between the stationary and personal measurement data for the total concentrations of airborne fungi (p>0.05). Revolving stationary and static stationary Button Samplers demonstrated similar performance characteristics for the collection of airborne fungi. This reflects the low sensitivity of the sampler's efficiency to the wind speed and direction. The results indicate that personal exposure of agricultural workers in confinements may be adequately assessed by placing several Button Samplers simultaneously operating in a static stationary mode throughout the work site.

Rapid counting of liquid-borne microorganisms by light scattering spectrometry

100%

Mainelis G., Gorny R. L., Willeke K., Reponen T.

Annals of Agricultural and Environmental Medicine

2005

tom 12

nr 1

Fast and sensitive techniques are needed to determine microorganism presence in liquid samples. In this research, the feasibility of using light scattering spectrometry for enumerating the biological particles in liquid samples was investigated. A particle size spectrometer was used to count six commonly found microbial species suspended in liquid with and without microbiological stains applied: Pseudomonas fluorescens, Micrococcus spp. vegetative cells and Bacillus subtilis var. niger endospores were stained with Acridine Orange and Crystal Violet, while Cladosporium cladosporioides, Penicillium melinii and Aspergillus versicolor fungi were stained with Acridine Orange and Lactophenol Cotton Blue. The counts obtained with the spectrometer were compared with those obtained with a phase-contrast microscope. It was found that the spectrometer counted about 32% of non-stained B. subtilis endospores and this percentage increased to almost 90% for stained endospores. Among the investigated species of fungi, the counting efficiency of P. melinii was the only one significantly affected by the application of the stain Lactophenol Cotton Blue: the fraction of counted fungal spores increased from 64% (non-stained spores) to about 100% (stained spores). The observed difference in counting efficiency may serve as a basis for differentiating biological from non-biological particles in liquid samples.

Ograniczanie wyników

2 Annals of Agricultural and Environmental Medicine

2 Reponen T.

1 Adhikari A.

1 Gorny R. L.

1 Grinshpun S. A.

1 Lee S. A.

1 Mainelis G.

1 Willeke K.

1 2005

1 2004

Wyniki wyszukiwania

Assessment of human exposure to airborne fungi in agricultural confinements: personal inhalable sampling versus stationary sampling

Rapid counting of liquid-borne microorganisms by light scattering spectrometry