Contamination of microbial foreign bodies in bottled mineral water in Tokyo, Japan.

A total of 292 imported and domestic bottled mineral waters (90 brands) obtained from consumers and retailers were examined, by eye, for observable microbial foreign bodies. Fungal and bacterial foreign contaminants were found in 45 samples of water (20 brands) and in 14 samples of water (10 brands), respectively. Of the samples of water found to be contaminated, 41 (22 brands) were imported and 18 (8 brands) were produced domestically. Of 22 brands that were contaminated, 20 (91%) had been sterilized by at least one method. Forty-eight (98%) of 49 samples confirmed with foreign bodies were less than 1 year old. Among the moulds isolated the most predominant genus was Penicillium, followed by Acremonium and Cladosporium. The samples that contained fungi were less contaminated by bacteria than those that contained observable bacterial foreign bodies.