Giardia cysts in tertiary-treated wastewater effluents: are they infective?
The infectivity of Giardia lamblia cysts recovered in primary- and tertiary-treated wastewater reclamation plant effluents was assessed in Mongolian gerbils (Meriones unguiculatus). Infections in gerbils inoculated with cysts from primary effluent concentrates demonstrated the presence of infectious G. lamblia cysts. No infectious cysts were detected by this method in concentrates of tertiary-treated effluents. This study found that determination of cyst concentrations without viability or infectivity assessment may significantly overestimate the potential health risks associated with protozoan cysts in tertiary-treated wastewater effluents.
Garcia
April
A
San Jose Creek Water Quality Laboratory, County Sanitation Districts of Los Angeles County, Whittier, CA 90601, USA. agarcia@lacsd.org
Yanko
William
W
Batzer
Glenda
G
Widmer
Giovanni
G
D000818:Animals; D005849:Gerbillinae; D005872:Giardia / Q000472:pathogenicity*; D033661:Oocysts; D011634:Public Health; D018570:Risk Assessment; D018675:Toxicity Tests; D014865:Waste Disposal, Fluid; D014871:Water Microbiology; D014881:Water Supply