Record Display for the EPA National Library Catalog


Main Title Effects of Ozone, Chlorine Dioxide, Chlorine, and Monochloramine on 'Cryptosporidium parvum' Oocyst Viability.
Author Korich, D. G. ; Mead, J. R. ; Madore, M. S. ; Sinclair, N. A. ; Sterling, C. R. ;
CORP Author Environmental Protection Agency, Cincinnati, OH. Risk Reduction Engineering Lab. ;Arizona Univ., Tucson.
Publisher c1990
Year Published 1990
Report Number EPA/600/J-90/278;
Stock Number PB91-145086
Additional Subjects Ozone ; Chlorine ; Parasitic diseases ; Cryptosporidium ; Giardia ; Potable water ; Disinfection ; Kinetics ; Mice ; Reprints ; Chlorine dioxide ; Monochloramine ; Oocysts
Library Call Number Additional Info Location Last
NTIS  PB91-145086 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 9p
Purified Cryptosporidium parvum oocysts were exposed to ozone, chlorine dioxide, chlorine, and monochloramine. Excystation and mouse infectivity were comparatively evaluated to assess oocyst viability. Ozone and chlorine dioxide more effectively inactivated oocysts than chlorine and monochloramine did. Greater than 90% inactivation as measured by infectivity was achieved by treating oocysts with 1 ppm of ozone (1 mg/liter) for 5 min. Exposure to 1.3 ppm of chlorine dioxide yielded 90% inactivation after 1 h, while 80 ppm of monochloramine required approximately 90 min. for 90% inactivation. The data indicate that C.parvum oocysts are 30 times more resistant to ozone and 14 times more resistant to chlorine dioxide than Giardia cysts exposed to these disinfectants under the same conditions. With the possible exception of ozone, the use of disinfectants alone should not be expected to inactivate C. parvum oocysts in drinking water. (Copyright (c) 1990, American Society for Microbiology.)