AIMS: To evaluate concentrations of airborne bacteria in university laboratories, hospital diagnostic laboratories, and a biowaste site in Seoul, Korea. To measure total airborne bacteria (TAB), the authors assessed sampling site, type of ventilation system, weather and detection of Gram-negative bacteria (GNB), indoors and outdoors. METHOD: An Andersen one-stage sampler (Quick Take 30; SKC Inc) was used to sample air at a flow rate of 28.3 l/min for 5 min on nutrient medium in Petri dishes located on the impactor. A total of 236 samples (TAB, 109 indoor and nine outdoor; GNB, 109 indoor and nine outdoor) were collected three times in each spot from the 11 facilities to compare airborne bacteria concentrations. RESULTS: TAB concentrations ranged from undetectable to 3451 CFU/m³ (mean 384 CFU/m³), and GNB concentrations from undetectable to 394 CFU/m³ (mean 17 CFU/m³). TAB concentrations were high in window-ventilated facilities and facilities in which GNB were detected; concentrations were also high when it was rainy (all p values <0.05). TAB concentrations correlated significantly with GNB (r=0.548, p<0.01), number of bacteria species (r=0.351, p<0.01) and temperature (r=0.297, p<0.01). The presence of heating, ventilating, and air conditioning (HVAC), the number of TAB species and the detection of GNB affect TAB concentrations in laboratories. CONCLUSIONS: It is recommended that special attention be given to regular control of indoor environments to improve the air quality of university and hospital laboratories.
AIMS: To evaluate concentrations of airborne bacteria in university laboratories, hospital diagnostic laboratories, and a biowaste site in Seoul, Korea. To measure total airborne bacteria (TAB), the authors assessed sampling site, type of ventilation system, weather and detection of Gram-negative bacteria (GNB), indoors and outdoors. METHOD: An Andersen one-stage sampler (Quick Take 30; SKC Inc) was used to sample air at a flow rate of 28.3 l/min for 5 min on nutrient medium in Petri dishes located on the impactor. A total of 236 samples (TAB, 109 indoor and nine outdoor; GNB, 109 indoor and nine outdoor) were collected three times in each spot from the 11 facilities to compare airborne bacteria concentrations. RESULTS: TAB concentrations ranged from undetectable to 3451 CFU/m³ (mean 384 CFU/m³), and GNB concentrations from undetectable to 394 CFU/m³ (mean 17 CFU/m³). TAB concentrations were high in window-ventilated facilities and facilities in which GNB were detected; concentrations were also high when it was rainy (all p values <0.05). TAB concentrations correlated significantly with GNB (r=0.548, p<0.01), number of bacteria species (r=0.351, p<0.01) and temperature (r=0.297, p<0.01). The presence of heating, ventilating, and air conditioning (HVAC), the number of TAB species and the detection of GNB affect TAB concentrations in laboratories. CONCLUSIONS: It is recommended that special attention be given to regular control of indoor environments to improve the air quality of university and hospital laboratories.
Authors: Sung Ho Hwang; Ik Mo Lee; Yun Keun Lee; Jeong Im Park; Kwang Won Rhie; Dong Uk Park; Chung Sik Yoon Journal: Environ Monit Assess Date: 2013-05-01 Impact factor: 2.513