Changes in Bacterial Aerosols with Height above Aeration Tanks
Publication: Journal of Environmental Engineering
Volume 122, Issue 5
Abstract
This paper describes the results of a study conducted to determine the fate of bacterial aerosol emissions from aeration tanks of an activated sludge treatment plant relative to the height above the liquid surface. Bacterial aerosols were collected using Andersen six-stage viable samplers positioned at heights ranging from 7.6 to 318 cm above the aeration tank liquid surface. Samples were analyzed for heterotrophic plate count (HPC), total coliform (TC), fecal coliform (FC), and fecal streptococci (FS). A statistical analysis of the data indicates that HPC and TC concentrations decreased exponentially with height above the aeration tank liquid surface. Fecal coliform and FS concentrations were low or below detection limits ( <4 cfu/m 3 ) in the collected samples and showed no decrease with height. This study demonstrates that a significant decline in number of aerosolized bacteria (leaving the surface of an aeration tank) occurs within the air column directly above the aeration tank liquid surface. Also, bacteria of potential public health concern, such as FC and FS, often reach nondetectable levels ( <4 cfu/m 3 ) within one meter above the liquid surface of these aeration tanks.
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References
1.
American Public Health Assoc. (1992). Standard methods for the examination of water and wastewater, 18th Ed., Washington, D.C.
2.
Andersen, A. A.(1958). “New sampler for the collection, sizing, and enumeration of viable airborne particles.”J. Bacteriology, 76, 471–474.
3.
Carnow, B., et al. (1979). “Health effects of aerosols emitted from an activated sludge plant.”EPA-600/1-79-019, USEPA, Cincinnati, Ohio.
4.
Fedorak, P. M., and Westlake, D. W. S.(1980). “Airborne bacterial densities at an activated sludge treatment plant.”J. Water Pollution Control Federation, 52, 2185–2192.
5.
Grinshpun, S. A., Chang, C., Nevalainen, A., and Willeke, K.(1994). “Inlet characteristics of bioaerosol samplers.”J. Aerosol Sci., 25(8), 1503–1522.
6.
Israeli, E., Shaffer, B. T., Hoyt, J. A., Lighthart, B., and Ganio, L. M.(1993). “Survival differences among freeze-dried genetically engineered and wild-type bacteria.”Appl. and Envir. Microbiol., 59, 594–598.
7.
Johnson, D. E., et al. (1979a). “Health implications of sewage treatment facilities.”EPA-600/1-78-032, U.S. Envir. Protection Agency, Cincinnati, Ohio.
8.
Johnson, D. E., Camann, D. E., Harding, H. J., and Sorber, C. A. (1979b). “Environmental monitoring of a wastewater treatment plant.”EPA-600/1-79-027, U.S. Envir. Protection Agency, Cincinnati, Ohio.
9.
Kenline, P. A., and Scarpino, P. V.(1972). “Bacterial air pollution from sewage treatment plants.”Am. Ind. Hyg. Assoc. J., 33, 346–352.
10.
Laitinen, S., Nevalainen, A., Kotimaa, M., Liesivuori, J., and Martikainen, P. S.(1992). “Relationship between bacterial counts and endotoxin concentrations in the air of wastewater treatment plants.”Appl. Envir. Microbiol., 58, 3774–3776.
11.
Larsen, R. I. (1971). “A mathematical model for relating air quality measurements to air quality standards.”USEPA Publ. AP Series AP-89, U.S. Govt. Printing Office, Washington, D.C.
12.
Lederberg, J., and Lederberg, E. M.(1952). “Replica plating and indirect selection of bacterial mutants.”J. Bacteriol., 63, 399–406.
13.
Lighthart, B., Shaffer, B. T., Marthi, B., and Ganio, L.(1991). “Trajectory of aerosol droplets from a sprayed bacterial suspension.”Appl. Envir. Microbiol., 57, 1006–1012.
14.
“Proceedings of USEPA symposium on wastewater aerosols and disease.” (1980). EPA-600/9-80-028, USEPA, Cincinnati, Ohio.
15.
Randall, C. W., and Ledbetter, J. O.(1966). “Bacterial air pollution from activated sludge units.”Am. Ind. Hyg. Assoc. J., 27, 506–519.
16.
Sawyer, B., Elenbogen, G., Rao, K. C., O'Brien, P., Zenz, D. R., and Lue-Hing, C.(1993). “Bacterial aerosol emission rates from municipal wastewater aeration tanks.”Appl. Envir. Microbiol., 59, 3183–3186.
17.
Walter, M. V., Marthi, B., Fieland, V. P., and Ganio, L. M.(1990). “Effect of aerosolization on subsequent bacterial survival.”Appl. Envir. Microbiol., 56, 3468–3472.
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Copyright © 1996 American Society of Civil Engineers.
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Published online: May 1, 1996
Published in print: May 1996
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