AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Temporal Distribution of Gram-negative (G-) and Gram-positive (G+) Bacterial Aerosols with Different Charge Polarity and Level
KAI WEI, Maosheng Yao, Peking University
Abstract Number: 627 Working Group: Bioaerosols: Characterization and Environmental Impact
Abstract Here, we investigated the temporal distribution of Gram-negative (G-) and Gram-positive (G+) bacterial aerosols with different charge polarity and level in both indoor and outdoor environments using an electrostatic sampling system (Aerobiologia, 27, 135-145). The bacterial aerosols with different charge polarity were collected separately using the electrostatic sampler with two square agar plates for morning, noon and afternoon. Selective media were used for culturing G+ and G- respectively, and obtained CFUs were further confirmed by Gram stain method.
Our preliminary data showed that for indoor bacterial aerosols the G+ prevailed over G- regardless of the charge polarity, while G- dominated for outdoor environment. The temporal distributions of G+ and G- with different charge polarity were shown to vary greatly with time and location, and no consistent trends were observed, which might be due to climatic conditions such as temperature, humidity, wind and differences in bioaerosol emission sources. It appears that outdoor aerosol charge levels turned to be more normally-distributed, while indoor aerosol charge levels seemed to be more skewed. Results from selective medium and Gram stain generally agreed well. Bacterial Gram types as well as their charge levels are important in terms with their lung inhalation and subsequent health effects. Information developed here not only described the temporal distribution of G+ and G- aerosols in different environments, but also yielded information that can help design better electrostatic sampling device.