Microbial contamination of fruit and vegetables and their disinfection.

We evaluated the microbial contamination of 17 types of vegetable and 10 types of fruit after 30-s washing with tap water with and without subsequent disinfection by 10-min immersion in 0.01% (100 ppm) sodium hypochlorite. The mean microbial contamination level of 9 types of leafy vegetable was 2.8 x 10(5) colony-forming units (CFU)/g after washing with water and 3.4 x 10(4) CFU/g after washing followed by disinfection. The mean microbial contamination level of 8 types of nonleafy vegetable was 3.4 x 10(4) CFU/g after washing with water and 1.0 x 10(4) CFU/g after washing followed by disinfection. The mean microbial contamination level of 10 types of unpeeled fleshy fruit was 9.3 x 10(3) CFU/g after washing with water and 1.3 x 10(3) CFU/g after washing followed by disinfection. The contaminants in vegetables and unpeeled fruit were similar after washing and after washing followed by disinfection, including Pseudomonas fluorescens and Pseudomonas aeruginosa. The contamination did not markedly decrease even after disinfection with sodium hypochlorite. However, the flesh of each type of peeled fruit showed no or only low levels of contamination (

Microbiological safety of bottled mineral water in patients susceptible to infections.

We evaluated the microbiological safety of bottled mineral water products commercially available in Japan. Of 10 bottled mineral water products manufactured in Japan, no bacteria or fungi were detected in 9 (90%), but 1 (10%) contained 1.8x10(3) colony-forming units (cfu)/mL. Of 12 bottled mineral water products manufactured in the EU, 11 (91.7%) contained 23-3.5x10(4) cfu/mL. On the other hand, of 5 bottled mineral water products manufactured in North America, 2 (40%) contained 2.3x10(2)-2.5x10(3) cfu/mL. The detected microorganisms were glucose-nonfermentative Gram-negative bacilli such as Brevundimonas vesicularis, Moraxella spp., and Burkholderia cepacia, but Pseudomonas aeruginosa was not detected in any product. For immunocompromised host patients being managed in ultra-clean rooms, the examined bottled mineral water products manufactured in Japan, except 1, were microbiologically safe.