title: Protozoal contamination of water used in Thai frozen food industry.
abstract: This study evaluated the prevalence of contamination of water that was used for food preparation. Since protozoal cysts can be found in small numbers in water, 1,000 liters of either untreated or treated water were filtered through activated carbon block filters (1 microm nominal porosity). Identification of protozoa was performed using specific monoclonal antibodies against Giardia and Cryptosporidium parasites followed by fluorescence microscopy. Twelve of 20 untreated water samples (60%) were found to be contaminated by Giardia cysts, with an average of 53.33 cysts/1,000 liters (geometric mean 39.43), whilst 7 samples (35%) were contaminated by Cryptosporidium oocysts, with an average of 28.57 oocysts/1,000 liters (geometric mean 26.92). Three samples of untreated water (15%) were positive for both organisms. In contrast, none of the treated water samples were contaminated.
authors.affiliation: Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Chantira
authors.initials: C
authors.lastname: Sutthikornchai
authors.forename: Chun
authors.initials: C
authors.lastname: Jantanavivat
authors.forename: Supatra
authors.initials: S
authors.lastname: Thongrungkiat
authors.forename: Talabporn
authors.initials: T
authors.lastname: Harnroongroj
authors.forename: Yaowalark
authors.initials: Y
authors.lastname: Sukthana
mesh_terms: D000818:Animals; D003458:Cryptosporidium / Q000302:isolation & purification*; D056890:Eukaryota / Q000302:isolation & purification*; D005506:Food Contamination / Q000706:statistics & numerical data*; D019649:Food Industry; D005628:Frozen Foods / Q000469:parasitology*; D005872:Giardia / Q000302:isolation & purification*; D006801:Humans; D013785:Thailand; D014876:Water Pollution / Q000706:statistics & numerical data*