Ozone Inactivation Kinetics of CRYPTOSPORIDIUM in Phosphate Buffer
Publication: Journal of Environmental Engineering
Volume 125, Issue 10
Abstract
The rate of inactivation of Cryptosporidium parvum oocysts by ozone in 0.05 M phosphate buffer at pH 6, 7, and 8 was studied at 22 ± 1°C in batch reactors. Infectivity in neonatal CD-1 mice was used as the criterion for oocyst viability. Ozone inactivation data were fitted to the Incomplete gamma Hom (I.g.H.) and Chick-Watson (n = 1) model, both of which incorporate a first-order rate constant for the disappearance of aqueous ozone during the contact time. For a 0.05 M phosphate buffer ranging in pH from 6 to 8, a single I.g.H. model was found to adequately describe the kinetics of Cryptosporidium inactivation by ozone at 22°C. The I.g.H. model for pH 6–8 was found to provide a significantly better fit to the ozone inactivation data when compared with the Chick-Watson model. The effect of pH on ozone inactivation kinetics was associated with ozone residual stability over the pH range of 6–8. The sensitivity of Cryptosporidium to ozone at 22°C was therefore not statistically different at pH 6 when compared with pH 8. The inactivation behavior of Cryptosporidium by ozone was characterized by a tailing-off effect, with approximately equal importance of ozone concentration and contact time. The I.g.H. model for pH 6–8 can be used as an aid in the design of ozone disinfection systems, and this robust fitted model was used to formulate ozone design criteria—the initial oxone residual required for a given contact time for 1, 2, and 3 log units inactivation of Cryptosporidium at 22°C. Uncertainty associated with the ozone design criteria for 2 log units inactivation was quantified using inverse prediction intervals. An ozone design criterion was established that gives a 95% probability of achieving 2 log units inactivation of Cryptosporidium at 22°C, corresponding to an approximate safety factor of 0.7 log units.
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References
1.
Arrowood, M. J., Hurd, M. R., and Mead, J. R. (1995). “A new method for evaluating experimental cryptosporidial parasite loads using immunofluorescent flow cytometry.” J. Parasitology, 81(3), 404–409.
2.
Bard, Y. (1974). Nonlinear parameter estimation. Academic, New York.
3.
Barer, M. R., and Wright, A. E. (1990). “A review: Cryptosporidium and water.” Letters Appl. Microbiol., 11, 271–277.
4.
Bates, D. M., and Watts, D. G. (1988). Nonlinear regression analysis and its applications. Wiley, New York.
5.
Belosevic, M., et al. (1997). “Nucleic acid stains as indicators of Cryptosporidium parvum oocyst viability.” Int. J. Parasitology, 27(7), 787–798.
6.
Botzenhart, K., Tarcson, G. M., and Ostruschka, M. (1993). “Inactivation of bacteria and coliphages by ozone and chlorine dioxide in a continuous flow reactor.” Water Sci. and Technol., 27(3–4), 363–370.
7.
Brand, R. J., Pinnock, D. E., and Jackson, K. L. (1973). “Large sample confidence bands for the logistic response curve and its inverse.” Am. Statistician, 27(4), 157–160.
8.
Cochran, W. G. (1973). “Experiments for nonlinear functions.” J. Am. Stat. Assoc., 68(344), 771–781.
9.
Crozes, G., White, P., Bench, B., and Hagstrom, J. (1998). “Evaluation of ozone for Cryptosporidium inactivation and atrazine oxidation in a lime softening plant.” Ozone Sci. Engrg., 20(3), 177–190.
10.
Donaldson, J. R., and Schnabel, R. B. (1987). “Computational experience with confidence regions and confidence intervals for nonlinear least squares.” Technometrics, 29(1), 67–82.
11.
Fair, G. M., Morris, J. C., Chang, S. L., Weil, I., and Burden, R. P. (1948). “The behavior of chlorine as a water disinfectant.” J. AWWA, 40(10), 1051–1061.
12.
Farooq, S., Chian, E. S. K., and Engelbrecht, R. S. (1977). “Basic concepts in disinfection with ozone.” J. Water Pollution Control Fed., 49, 1818–1831.
13.
Fayer, R., and Ungar, B. L. P. (1986). “Cryptosporidium spp. and cryptosporidiosis.” Microbiol. Rev., 50(4), 458–483.
14.
Finch, G. R., Black, E. K., Gyürék, L. L., and Belosevic, M. (1993a). “Ozone inactivation of Cryptosporidium parvum in demand-free phosphate buffer determined by in vitro excystation and animal infectivity.” Appl. Envir. Microbiol., 59(12), 4203–4210.
15.
Finch, G. R., Black, E. K., Gyürék, L. L., and Belosevic, M. (1994). Ozone disinfection of Giardia and Cryptosporidium. American Water Works Association Research Foundation and American Water Works Association, Denver.
16.
Finch, G. R., Daniels, C. W., Black, E. K., Schaefer, F. W., III, and Belosevic, M. (1993b). “Dose response of Cryptosporidium parvum in outbred neonatal CD-1 mice.” Appl. Envir. Microbiol., 59(11), 3661–3665.
17.
Finch, G. R., Gyürék, L. L., Liyanage, L. R. J., and Belosevic, M. (1997). Effect of various disinfection methods on the inactivation of Cryptosporidium. American Water Works Association Research Foundation and American Water Works Association, Denver.
18.
Fisher, R. A., Thornton, H. G., and Mackenzie, W. A. (1922). “The accuracy of the plating method of estimating the density of bacterial populations.” Ann. Appl. Biol., 9, 325–359.
19.
Gyürék, L. L., and Finch, G. R. (1998). “Modeling water treatment chemical disinfection kinetics.”J. Envir. Engrg., ASCE, 124(9), 783–793.
20.
Gyürék, L. L., Finch, G. R., and Belosevic, M. (1997). “Modeling chlorine inactivation requirements of Cryptosporidium parvum oocysts.”J. Envir. Engrg., ASCE, 123(9), 865–875.
21.
Haas, C. N., and Joffe, J. (1994). “Disinfection under dynamic conditions—modification of Hom model for decay.” Envir. Sci. and Technol., 28(7), 1367–1369.
22.
Haas, C. N., Joffe, J., Heath, M., Jacangelo, J., and Anmangandla, U. (1998). “Predicting disinfection performance in continuous flow systems from batch disinfection kinetics.” Water Sci. and Technol., 38(6), 171–179.
23.
Hart, E. J., Sehested, K., and Holcman, J. (1983). “Molar absorptivities of ultraviolet and visible bands of ozone in aqueous solutions.” Analytical Chem., 55, 46–49.
24.
Hayes, E. B., et al. (1989). “Large community outbreak of cryptosporidiosis due to contamination of a filtered public water supply.” New England J. Medicine, 320(21), 1372–1376.
25.
Hiatt, C. W. (1964). “Kinetics of the inactivation of viruses.” Bacteriol. Rev., 28(2), 150–163.
26.
Hoigné, J. (1988). “The chemistry of ozone in water.” Proc., 10th Brown Boveri Symp. on Process Technol. for Water Treatment, Plenum, New York, 121–143.
27.
Hoigné, J., and Bader, H. (1994). “Characterization of water quality criteria for ozonation processes. Part II: Lifetime of added ozone.” Ozone Sci. Engrg., 16(2), 121–134.
28.
Hom, L. W. (1972). “Kinetics of chlorine disinfection in an ecosystem.”J. Sanit. Engrg. Div., ASCE, 98(1), 183–193.
29.
Katzenelson, E., Koerner, G., Biedermann, N., Peleg, M., and Shuval, H. I. (1979). “Measurement of the inactivation kinetics of poliovirus by ozone in a fast flow mixer.” Appl. Envir. Microbiol., 37(4), 715–718.
30.
Kilani, R. T., and Sekla, L. (1987). “Purification of Cryptosporidium oocysts and sporozoites by cesium chloride and percoll gradients.” Am. J. Tropical Medicine and Hygiene, 36, 505–508.
31.
Korich, D. G., Mead, J. R., Madore, M. S., Sinclair, N. A., and Sterling, C. R. (1990). “Effects of ozone, chlorine dioxide, chlorine, and monochloramine on Cryptosporidium parvum oocyst viability.” Appl. Envir. Microbiol., 56(5), 1423–1428.
32.
Labatiuk, C. W., Belosevic, M., and Finch, G. R. (1992). “Factors influencing the infectivity of Giardia muris cysts following ozone inactivation in laboratory and natural waters.” Water Res., 26(6), 733–743.
33.
Langlais, B., Reckhow, D. A., and Brink, D. R. (1991). Ozone in water treatment: Application and engineering. Lewis, Chelsea, Mich.
34.
Lev, O., and Regli, S. (1992). “Evaluation of ozone disinfection systems: Characteristic time T.”J. Envir. Engrg., ASCE, 118(2), 268–285.
35.
Li, H., Finch, G. R., Neumann, N. F., and Belosevic, M. (1998). “Inactivation of Cryptosporidium by chlorine dioxide at 1°C.” Proc., Water Quality Tech. Conf., American Water Works Association, Denver.
36.
MacKenzie, W. R., et al. (1994). “A massive outbreak in Milwaukee of Cryptosporidium infection transmitted through the public water supply.” New England J. Medicine, 331(3), 161–167.
37.
Majumdar, B., Ceckler, W. H., and Sproul, O. J. (1973). “Inactivation of poliovirus in water by ozonation.” J. Water Pollution Control Fed., 45(12), 2433–2443.
38.
Neter, J., Wasserman, W., and Kutner, M. H. (1989). Applied linear regression models. Irwin, Boston.
39.
Peeters, J. E., Mazás, E. A., Masschelein, W. J., Martinez de Maturana, I. V., and Debacker, E. (1989). “Effect of disinfection of drinking water with ozone or chlorine dioxide on survival of Cryptosporidium parvum oocysts.” Appl. Envir. Microbiol., 55(6), 1519–1522.
40.
Perrine, D., Georges, P., and Langlais, B. (1990). `Efficacité de l'ozonation des eaux sur l'inactivation des oocystes de Cryptosporidium.” Bulletin de l'Academie Nationale de Medecine, 174(6), 845–850 (in French).
41.
Pett, B., Smith, F., Stendahl, D., and Welker, R. (1994). “Cryptosporidiosis outbreak from an operations point of view: Kitchener-Waterloo, Ontario, spring 1993.” Proc., Water Quality Technol. Conf., American Water Works Association, Denver.
42.
Roustan, M., Debellefontaine H., Do-Quang, Z., and Duguet, J.-P. (1998). “Development of a method for the determination of ozone demand of a water.” Ozone Sci. Engrg., 20(6), 513–520.
43.
Rush, B. A., Chapman, P. A., and Ineson, R. W. (1990). “A probable waterborne outbreak of cryptosporidiosis in the Sheffield area.” J. Medical Microbiol., 32, 239–242.
44.
Seber, G. A. F. (1977). Linear regression analysis. Wiley, New York.
45.
Seber, G. A. F., and Wild, C. J. (1989). Nonlinear regression, Wiley, New York.
46.
Wickramanayake, G. B., Rubin, A. J., and Sproul, O. J. (1984). “Inactivation of Naegleria and Giardia cysts in water by ozonation.” J. Water Pollution Control Fed., 56(8), 983–988.
Information & Authors
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Published In
Journal of Environmental Engineering
Volume 125 • Issue 10 • October 1999
Pages: 913 - 924
History
Received: Mar 16, 1998
Published online: Oct 1, 1999
Published in print: Oct 1999
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