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Evaluation of applicability of the Sartorius Airport MD8 sampler for detection of Bacillus endospores in indoor air.

Lewandowski R, Kozłowska K, Szpakowska M, Trafny EA - Environ Monit Assess (2012)

Bottom Line: Different concentrations of bioaerosol were generated inside the test chamber filled with either the high-efficiency particulate air (HEPA)-filtered air or with the ambient room air.The microorganisms present in the ambient room air interfere with precise quantification of Bacillus endospores when their concentration is relatively low.The results of this study may be helpful in critical assessment of the results obtained from monitoring the air for bacterial endospores.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland.

ABSTRACT
This study was designed to evaluate the measuring range and lowest limit of detection of Bacillus endospores in the ambient room air when the Sartorius MD8 sampler, and two different culture methods for bacterial enumeration were used. Different concentrations of bioaerosol were generated inside the test chamber filled with either the high-efficiency particulate air (HEPA)-filtered air or with the ambient room air. The detection of endospores in the HEPA-filtered air was achievable: (1) when they were aerosolized at a concentration above 7.56 × 10(3) CFU/m(3) and analyzed with spread plate method, and (2) when they were aerosolized at a concentration above 4.00 × 10(2) CFU/m(3) and analyzed with pour plate method. The detection of endospores in the ambient room air was possible: (1) when they were aerosolized at a concentration above 9.1 × 10(3) CFU/m(3) and analyzed with spread plate method, and (2) when they were aerosolized at a concentration above 5.6 × 10(2) CFU/m(3) and analyzed with pour plate method. The microorganisms present in the ambient room air interfere with precise quantification of Bacillus endospores when their concentration is relatively low. The results of this study may be helpful in critical assessment of the results obtained from monitoring the air for bacterial endospores.

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Relationship between the numbers of B. atrophaeus spores collected using BioSampler (a), Airport MD8 (b), and six-stage Andersen impactor (c) and the total number of spores aerosolized within the chamber filled with the HEPA-filtered air. Data are shown as the mean log values (±SD) per cubic meter of air. Linear regression coefficients (R2) are shown in the upper right corner of each graph
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Fig1: Relationship between the numbers of B. atrophaeus spores collected using BioSampler (a), Airport MD8 (b), and six-stage Andersen impactor (c) and the total number of spores aerosolized within the chamber filled with the HEPA-filtered air. Data are shown as the mean log values (±SD) per cubic meter of air. Linear regression coefficients (R2) are shown in the upper right corner of each graph

Mentions: In a first step of experiments, in order to compare the measuring range of the three devices widely used for air sampling, we collected the bioaerosols of various concentrations [in a range from 3.43 × 102 (±1.68 × 102) to 8.05 × 108 (±2.32 × 108) CFU/m3] generated in a test chamber filled with a HEPA-filtered air. The number of B. atrophaeus endospores in these bioaerosol samples collected using the Airport MD8 sampler, the SKC BioSampler, and the Andersen six-stage impactor were dependent on the concentration of the endospores aerosolized within the chamber. As shown in Fig. 1, the linear regression coefficient (R2) for the data obtained with the BioSampler was 0.94, when the number of the endospores aerosolized was in the range from 6.01 × 104 (±1.29 × 104) to 8.05 × 108 (±2.32 × 108) CFU/m3 of air. A similar relationship (R2 = 0.95) was observed when the number of total CFU aerosolized inside the chamber [from 7.56 × 103 (±1.58 × 103) to 4.47 × 108 (±1.03 × 108) CFU/m3 of air] was plotted versus the concentration of the endospores taken with the Airport MD8 sampler. A high regression coefficient (R2 = 0.94) was also observed when bioaerosol samples were taken using the Andersen six-stage impactor; however, only when the number of aerosolized endospores was in the range from 4.80 × 102 (±1.79 × 102) to 5.31 × 104 (±1.31 × 104) CFU/m3 of air. Thus, the measuring range of the Andersen impactor was observed in the lowest concentration range of the bacteria examined in this study.Fig. 1


Evaluation of applicability of the Sartorius Airport MD8 sampler for detection of Bacillus endospores in indoor air.

Lewandowski R, Kozłowska K, Szpakowska M, Trafny EA - Environ Monit Assess (2012)

Relationship between the numbers of B. atrophaeus spores collected using BioSampler (a), Airport MD8 (b), and six-stage Andersen impactor (c) and the total number of spores aerosolized within the chamber filled with the HEPA-filtered air. Data are shown as the mean log values (±SD) per cubic meter of air. Linear regression coefficients (R2) are shown in the upper right corner of each graph
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3585950&req=5

Fig1: Relationship between the numbers of B. atrophaeus spores collected using BioSampler (a), Airport MD8 (b), and six-stage Andersen impactor (c) and the total number of spores aerosolized within the chamber filled with the HEPA-filtered air. Data are shown as the mean log values (±SD) per cubic meter of air. Linear regression coefficients (R2) are shown in the upper right corner of each graph
Mentions: In a first step of experiments, in order to compare the measuring range of the three devices widely used for air sampling, we collected the bioaerosols of various concentrations [in a range from 3.43 × 102 (±1.68 × 102) to 8.05 × 108 (±2.32 × 108) CFU/m3] generated in a test chamber filled with a HEPA-filtered air. The number of B. atrophaeus endospores in these bioaerosol samples collected using the Airport MD8 sampler, the SKC BioSampler, and the Andersen six-stage impactor were dependent on the concentration of the endospores aerosolized within the chamber. As shown in Fig. 1, the linear regression coefficient (R2) for the data obtained with the BioSampler was 0.94, when the number of the endospores aerosolized was in the range from 6.01 × 104 (±1.29 × 104) to 8.05 × 108 (±2.32 × 108) CFU/m3 of air. A similar relationship (R2 = 0.95) was observed when the number of total CFU aerosolized inside the chamber [from 7.56 × 103 (±1.58 × 103) to 4.47 × 108 (±1.03 × 108) CFU/m3 of air] was plotted versus the concentration of the endospores taken with the Airport MD8 sampler. A high regression coefficient (R2 = 0.94) was also observed when bioaerosol samples were taken using the Andersen six-stage impactor; however, only when the number of aerosolized endospores was in the range from 4.80 × 102 (±1.79 × 102) to 5.31 × 104 (±1.31 × 104) CFU/m3 of air. Thus, the measuring range of the Andersen impactor was observed in the lowest concentration range of the bacteria examined in this study.Fig. 1

Bottom Line: Different concentrations of bioaerosol were generated inside the test chamber filled with either the high-efficiency particulate air (HEPA)-filtered air or with the ambient room air.The microorganisms present in the ambient room air interfere with precise quantification of Bacillus endospores when their concentration is relatively low.The results of this study may be helpful in critical assessment of the results obtained from monitoring the air for bacterial endospores.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland.

ABSTRACT
This study was designed to evaluate the measuring range and lowest limit of detection of Bacillus endospores in the ambient room air when the Sartorius MD8 sampler, and two different culture methods for bacterial enumeration were used. Different concentrations of bioaerosol were generated inside the test chamber filled with either the high-efficiency particulate air (HEPA)-filtered air or with the ambient room air. The detection of endospores in the HEPA-filtered air was achievable: (1) when they were aerosolized at a concentration above 7.56 × 10(3) CFU/m(3) and analyzed with spread plate method, and (2) when they were aerosolized at a concentration above 4.00 × 10(2) CFU/m(3) and analyzed with pour plate method. The detection of endospores in the ambient room air was possible: (1) when they were aerosolized at a concentration above 9.1 × 10(3) CFU/m(3) and analyzed with spread plate method, and (2) when they were aerosolized at a concentration above 5.6 × 10(2) CFU/m(3) and analyzed with pour plate method. The microorganisms present in the ambient room air interfere with precise quantification of Bacillus endospores when their concentration is relatively low. The results of this study may be helpful in critical assessment of the results obtained from monitoring the air for bacterial endospores.

Show MeSH
Related in: MedlinePlus