Survival of microorganisms on antimicrobial filters and the removal efficiency of bioaerosols in an environmental chamber.
Exposure to bioaerosols causes various adverse health effects including infectious and respiratory diseases, and hypersensitivity. Controlling exposure to bioaerosols is important for disease control and prevention. In this study, we evaluated the efficacies of various functional filters coated with antimicrobial chemicals in deactivating representative microorganisms on filters or as bioaerosols. Tested functional filters were coated with different chemicals that included (i) Ginkgo and sumac, (ii) Ag-apatite and guanidine phosphate, (iii) SiO2, ZnO, and Al2O3, and (iv) zeolite. To evaluate the filters, we used a model ventilation system (1) to evaluate the removal efficiency of bacteria (Escherichia coli and Legionella pneumophila), bacterial spores (Bacillus subtilis spore), and viruses (MS2 bacteriophage) on various functional filters, and (2) to characterize the removal efficiency of these bioaerosols. All experiments were performed at a constant temperature of 25 degrees C and humidity of 50%. Most bacteria (excluding B. subtilis) rapidly decreased on the functional filter. Therefore, we confirmed that functional filters have antimicrobial effects. Additionally, we evaluated the removal efficiency of various bioaerosols by these filters. We used a six-jet collision nebulizer to generate microbial aerosols and introduced it into the environmental chamber. We then measured the removal efficiency of functional filters with and without a medium-efficiency filter. Most bioaerosol concentrations did not significantly decrease by the functional filter only but decreased by a combination of functional and medium-efficiency filter. In conclusion, functional filters could facilitate biological removal of various bioaerosols, but physical removal of these by functional was minimal. Proper use of chemical-coated filter materials could reduce exposure to these agents.
Institute of Health and Environment, Department of Environmental Health, School of Public Health, Seoul National University, Seoul, Korea.
Sung Yeon
SY
Kim
Misoon
M
Kim
Sunghee
S
Lee
JungEun
J
Lee
GwangPyo
G
Ko
D000336:Aerosols; D000391:Air Microbiology; D000890:Anti-Infective Agents; D001419:Bacteria / Q000302:isolation & purification*; D003666:Decontamination; D004784:Environmental Monitoring / Q000295:instrumentation*; D005374:Filtration / Q000295:instrumentation* / Q000379:methods; D006813:Humidity; D053122:Influenza A Virus, H3N2 Subtype / Q000302:isolation & purification*; D013171:Spores, Bacterial / Q000302:isolation & purification; D018709:Statistics, Nonparametric; D013696:Temperature
D000336:Aerosols; D000890:Anti-Infective Agents