Occurrence of parasites on fruits and vegetables in Norway

Between August 1999 and January 2001, samples of various fruits and vegetab les obtained within Norway were analyzed by published methods for parasite contamination. Neither Cyclospora oocysts nor Ascaris (or other helminth) e ggs were detected on any of the samples examined for these parasites. Howev er, of the 475 samples examined for Cryptosporidium oocysts and Giardia cys ts, 29 (6%) were found to be positive. No samples were positive for both pa rasites. Of the 19 Cryptosporidium-positive samples, 5 (26%) were in lettuc es, and 14 (74%) in mung bean sprouts. Of the 10 Giardia-positive samples, 2 (20%) were in dill, 2 (20%) in lettuce, 3 (30%) in mung bean sprouts, 1 ( 10%) in radish sprouts, and 2 (20%) in strawberries. Mung bean sprouts were significantly more likely to be contaminated with Cryptosporidium oocysts or Giardia cysts than the other fruits and vegetables. Concentrations of Cr yptosporidium and Giardia detected were generally low (mean of approximatel y 3 [oo]cysts per 100 g produce). Although some of the contaminated produce was imported (the majority, if sprouted seeds are excluded), there was no association between imported produce and detection of parasites. Cryptospor idium oocysts and Giardia cysts were also detected in water samples concern ed with field irrigation and production of bean sprouts within Norway. This is the first time that parasites have been detected on vegetables and frui t obtained in a highly developed, wealthy country, without there being an o utbreak situation. These findings may have important implications for globa l food safety.