Effects of ozone, chlorine dioxide, chlorine, and monochloramine on Cryptosporidium parvum oocyst viability.
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TLDR
The data indicate that C. parvum oocysts are 30 times moreresistant to ozone and 14 times more resistant to chlorine dioxide than Giardia cysts exposed to these disinfectants under the same conditions.Abstract:
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 chlorine and 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.read more
Citations
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Effect of different sanitizers on microbial and sensory quality of fresh-cut potato strips stored under modified atmosphere or vacuum packaging
TL;DR: In this article, the effectiveness of different traditional and non-traditional sanitizers on the sensory and microbial quality of fresh-cut potatoes stored under passive modified atmosphere packaging (MAP) and vacuum packaging was investigated.
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Risk and control of waterborne cryptosporidiosis
TL;DR: Water treatment has focused on UV and ozone disinfection as most promising for the inactivation of this protozoan pathogen, but advances in detection methodologies have shown that human wastes are often the source of the contamination.
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Effect of high temperature on infectivity of Cryptosporidium parvum oocysts in water.
TL;DR: Cryptosporidium parvum oocysts suspended in 0.5 ml of distilled water were pipetted into plastic vials which were inserted into wells in the heated metal block of a thermal DNA cycler to test for infectivity in BALB/c mouse pups.
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Ozone inactivation of Cryptosporidium parvum in demand-free phosphate buffer determined by in vitro excystation and animal infectivity.
TL;DR: It was found that excystation consistently underestimated inactivation when compared with animal infectivity (P < or = 0.05) and as inactivations increased, the difference between excy station and infectivity also increased.
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Disinfection potential of ozone, ultraviolet-C and their combination in wash water for the fresh-cut vegetable industry.
TL;DR: O(3) and O(3)-UV are alternatives to other sanitizers used in the fresh-cut washing processes and should be used in specific applications such as carrot wash water, where levels of undesirable microbial and chemical constituents are lower than other vegetable wash water.
References
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Book
Standard methods for the examination of water and wastewater
TL;DR: The most widely read reference in the water industry, Water Industry Reference as discussed by the authors, is a comprehensive reference tool for water analysis methods that covers all aspects of USEPA-approved water analysis.
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Determination of ozone in water by the indigo method
TL;DR: In this article, the decolorization of indigo trisulfonate (600 nm, pH below 4) was used to determine the concentration of aqueous ozone in the range 0.005 −30 mg 1−1.
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Acute enterocolitis in a human being infected with the protozoan Cryptosporidium.
TL;DR: It is suggested, on the basis of the severity of the clinical symptoms, and on the pathological changes in the rectum, that the organism in this case is likely to have been the cause of the enterocolitis and thus to have was a pathogen rather than a commensal.
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Isolation of Cryptosporidium oocysts and sporozoites using discontinuous sucrose and isopycnic Percoll gradients.
TL;DR: Techniques for the large-scale isolation of Cryptosporidium oocysts and sporozoites, obtained from the feces of experimentally infected Holstein calves, were developed employing discontinuous sucrose gradients and isopycnic Percoll gradients.
Journal ArticleDOI
Large Community Outbreak of Cryptosporidiosis Due to Contamination of a Filtered Public Water Supply
Edward B. Hayes,Thomas Matte,Thomas R. O'Brien,Thomas W. McKinley,Gary S. Logsdon,Joan B. Rose,Beth L. P. Ungar,David M. Word,Margaret A. Wilson,Earl G. Long,Eugene S. Hurwitz,Dennis D. Juranek +11 more
TL;DR: Current standards for the treatment of public water supplies may not prevent the contamination of drinking water by Cryptosporidium, with consequent outbreaks of cryptosporidiosis, it is concluded.