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PubMed · 9366597

Produce handling and processing practices.

Abstract

In the past decade, outbreaks of human illness associated with the consumption of raw vegetables and fruits (or unpasteurized products produced from them) have increased in the United States. Changes in agronomic, harvesting, distribution, processing, and consumption patterns and practices have undoubtedly contributed to this increase. Pathogens such as Listeria monocytogenes, Clostridium botulinum, and Bacillus cereus are naturally present in some soil, and their presence on fresh produce is not rare. Salmonella, Escherichia coli O157:H7, Campylobacter jejuni, Vibrio cholerae, parasites, and viruses are more likely to contaminate fresh produce through vehicles such as raw or improperly composted manure, irrigation water containing untreated sewage, or contaminated wash water. Contact with mammals, reptiles, fowl, insects, and unpasteurized products of animal origin offers another avenue through which pathogens can access produce. Surfaces, including human hands, which come in contact with whole or cut produce represent potential points of contamination throughout the total system of growing, harvesting, packing, processing, shipping, and preparing produce for consumption. Treatment of produce with chlorinated water reduces populations of pathogenic and other microorganisms on fresh produce but cannot eliminate them. Reduction of risk for human illness associated with raw produce can be better achieved through controlling points of potential contamination in the field; during harvesting; during processing or distribution; or in retail markets, food-service facilities, or the home.

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BibTeXRIS

L R Beuchat, J H Ryu. Produce handling and processing practices.. https://doi.org/10.3201/eid0304.970407

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Microbial contamination of 'sterile water' used in Japanese hospitals.

We examined the following samples of water from 10 hospitals for microbial contamination: water obtained using an ultra filtration system (UF water), a reverse osmosis system (RO water), a water distillation system (distilled water) and tap water. UF water and RO water are used for handwashing before surgery, and distilled water for the preparation of drugs. All 10 samples of tap water examined were contaminated with < 10 colony forming units (cfu)/mL. Thirteen (68%) of 19 samples of UF water, nine (53%) of 17 samples of RO water and 15 (79%) of 19 samples of distilled water were contaminated with 10(1)-10(4) cfu/mL. The majority of micro-organisms were non-fermentative bacteria such as Sphingomonas paucimobilis and CDC gr. IV C-2. Japanese hospitals commonly use UF water and RO water for preoperative handwashing under the assumption that it is sterile. Our results suggest, however, that these types of water are inferior microbiologically to tap water. Distilled water from the dispensary was also contaminated with micro-organisms. The available chlorine content of tap water was 0.17-0.42 ppm and that of UF water (from tap water) 0-0.06 ppm. There was no available chlorine in RO water or distilled water (each from tap water). The reduction or disappearance of available chlorine appears to be associated with microbial contamination of UF water, RO water and distilled water.

Chlorine