Chemistry Seminar Series: Xing-Fang Li

Detection of Pathogens and Trace Disinfection byproducts of Health Relevance

Xing-Fang Li
Professor 
Division of Analytical and Environmental Toxicology
Department of Laboratory Medicine and Pathology
University of Alberta

Wednesday, April 27, 2016
10:00 a.m.
C2 361 (Reading Room)

Host:  Janusz Pawliszyn

Abstract:  Disinfection of drinking water most effectively prevents water-borne diseases. To date, elimination of pathogens and toxic disinfection byproducts (DBPs) remains challenging. Our research on drinking water safety focuses on (1) ultra-sensitive bioassays for pathogen detection, (2) identification of new DBPs of toxicological relevance, and (3) mechanisms of toxicity of new DBPs. Detection of viable pathogens is particularly important to water safety. We have selected novel aptamers specifically targeting pathogens and developed unique bioassays for detection of viable but not culturable (VBNC) pathogens.

Common disinfection treatments unavoidably generate byproducts resulting from reactions between natural organic matter in the source water and disinfectants. The majority (~70%) of disinfection byproducts (DBPs) in treated water remain unidentified. Potential adverse health effects observed in epidemiological studies drive analytical research to identify and determine what DBPs may contribute to these health risks. Our analytical developments enabled the characterization of emerging DBPs and the investigation into the occurrence of these DBPs, e.g. halobenzoquinones (HBQs). Our in vitro toxicological studies of HBQs support that these DBPs induce a wide range of damages to cells, proteins and DNA. These studies contribute to a better understanding of the molecular mechanisms of toxicity of HBQs and the potential health effects of HBQs.Anchor

Three recent publications:

1.   Wang, W.; Qian, Y.; Jmaiff, L.K.; Hrudey, S.E.; Krasner, S.; Li, X.-F. Precursors of halobenzoquinones and their removal during drinking water treatment processes. Environ. Sci. Technol. 49, 9898−9904 (2015).
2.   Li, J.; Wang, W.; Moe, B.; Wang, H.; Li, X.-F. Chemical and toxicological characterization of halobenzoquinones, an emerging class of disinfection byproducts. Chem. Res. Toxicol. 28, 306–318 (2015).
3.   Liu, Y.; Wang, C.; Li, F.; Shen, S.; Tyrrell, D.L.J.; Le, X.C.; Li, X-F. DNase-mediated single-cycle selection of aptamers for proteins blotted on a membrane. Anal. Chem. 84, 7603-7606 (2012).