Photocatalytic inactivation of Cryptosporidium parvum with TiO2 and low-pressure ultraviolet irradiation

Authors

Hodon Ryu, National Science Foundation Water Quality CenterFollow
Daniel Gerrity, University of Nevada, Las VegasFollow
John C. Crittenden, Arizona State UniversityFollow
Morteza Abbaszadegan, Arizona State UniversityFollow

Document Type

Article

Publication Date

3-2008

Publication Title

Water Research

Volume

42

Issue

6-7

First page number:

1523

Last page number:

1530

Abstract

This study investigated the efficacy of low-pressure ultraviolet (UV) irradiation and the synergistic effect of UV/titanium dioxide (TiO₂) photocatalysis on Cryptosporidium parvum oocyst inactivation. At UV doses of 2.7, 8.0, and 40 mJ/cm², oocyst inactivation was 1.3, 2.6, and 3.3 log₁₀, respectively. Reactive oxygen species (ROS) generated by longwave UV radiation (>315 nm) and TiO₂ achieved less than 0.28-log inactivation. However, the synergistic effect of germicidal (254 nm) UV and TiO₂ resulted in 2-log and 3-log oocyst inactivation with 4.0 and 11.0 mJ/cm², respectively. Therefore, using TiO₂ in combination with UV reduced the dose requirement for 3-log inactivation by 56%. An approximate 1-log decrease in inactivation of oocysts was observed with nanopure water in comparison to buffered water, whereas changes in pH from 6 to 8 had little effect on the photocatalytic inactivation of oocysts in either matrix (P>0.1).

Keywords

Cryptosporidium parvum; Cryptosporidium inactivation; Integrated cell culture quantitative PCR; Photocatalysis; Titanium dioxide; UV/TiO2 photocatalysis; Water — Purification — Photocatalysis; Water — Purification — Ultraviolet treatment

Disciplines

Chemistry | Environmental Engineering | Environmental Health and Protection | Environmental Sciences | Water Resource Management

Language

English

Permissions

Use Find in Your Library, contact the author, or use interlibrary loan to garner a copy of the article. Publisher copyright policy allows author to archive post-print (author’s final manuscript). When post-print is available or publisher policy changes, the article will be deposited

Publisher Citation

Hodon Ryu, Daniel Gerrity, John C. Crittenden, Morteza Abbaszadegan, Photocatalytic inactivation of Cryptosporidium parvum with TiO2 and low-pressure ultraviolet irradiation, Water Research, Volume 42, Issues 6–7, March 2008, Pages 1523-1530, ISSN 0043-1354, 10.1016/j.watres.2007.10.037.

Repository Citation

Ryu, H., Gerrity, D., Crittenden, J. C., Abbaszadegan, M. (2008). Photocatalytic inactivation of Cryptosporidium parvum with TiO2 and low-pressure ultraviolet irradiation. Water Research, 42(6-7), 1523-1530.
http://dx.doi.org/10.1016/j.watres.2007.10.038