Short Communication Water used to moisten vegetables is a source of Escherichia coli and protozoan parasite contamination at markets in Hanoi, Vietnam Nguyen Thuy Tram and Anders Dalsgaard ABSTRACT The study was done to assess the level of fecal (Escherichia coli) and protozoan parasite (Cryptosporidium spp. and Giardia spp.) contamination in water used by traders to moisten vegetables at markets in Hanoi, Vietnam. A total of 200 splashing water samples from markets located within eight districts were analyzed for E. coli and Cryptosporidium spp. and Giardia spp. (oo)cysts. Giardia cysts were found in 17 splashing water samples and Cryptosporidium oocysts in nine samples, with median values of 20 cysts ml À1 and 10 oocysts ml À1 , respectively. E. coli was found with a median concentration of 636 cfu ml À1 and its occurrence was negatively correlated with the numbers of protozoan parasites. The splashing water was kept in buckets that were rarely cleaned and often used for handwashing. The finding of these pathogens in splashing water is likely to represent real food safety hazards. Nguyen Thuy Tram (corresponding author) Department of Microbiology, National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hanoi, Vietnam E-mail: tram@nihe.org.vn Anders Dalsgaard Department of Veterinary Diseases Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Groennegaardsvej 15, DK-1870, Frederiksberg C, Denmark Key words | Cryptosporidium spp., foodborne, Giardia spp., splashing water, waterborne INTRODUCTION Cryptosporidium and Giardia (oo)cysts are recognized as common waterborne pathogens found in surface water (lakes, streams, rivers, and reservoirs) and effluent from wastewater treatment plants (Khouja et al. ; Julio et al. ; Duris et al. ; Gallas-Lindemann et al. ; Xiao et al. ). These protozoan parasites have been detected on vegetables and in irrigation water used for crop production (Thurston-Enriquez et al. ; Vuong et al. ). Cryptosporidiosis and giardiasis are perceived more as waterborne than as foodborne diseases. (Oo) cysts are resistant to most disinfectants normally used for water treatment (Baldursson & Karanis ). Thus, con- taminated water appears to be a major source of protozoan parasites contamination of fresh produce (Chai- dez et al. ; Amoros et al. ). Cryptosporidium spp. and Giardia spp. might subsequently cause illness when fresh produce is consumed raw or with minimal heat treatment. Fresh produce may become contaminated with Crypto- sporidium spp. and Giardia spp. along the entire chain from field to kitchen, for example, when vegetables are har- vested, transported, stored, and sold. In Vietnam, vegetables are often washed in different types of water after harvest. At rural and urban markets, traders keep a bucket of water at their stall for splashing vegetables to keep them fresh and moist. Water from taps located within the market area, taps at public toilets or concrete water storage tanks are stored in buckets that are rarely cleaned and the water may also be used for hand washing. This study therefore aimed to access the level of fecal (Escherichia coli) and protozoan parasites 896 Short Communication © IWA Publishing 2014 Journal of Water and Health | 12.4 | 2014 doi: 10.2166/wh.2014.145 Downloaded from http://iwaponline.com/jwh/article-pdf/12/4/896/395860/896.pdf by guest on 15 January 2023