Sanitizing alternatives for Escherichia coli and Salmonella typhimurium on bell peppers at household kitchens.

Fresh fruits and vegetables are known to play an important role as carriers of disease-causing organisms in household kitchens. The aims of this study were to assess and compare the effectiveness of sodium hypochlorite, organic acid-based and silver-based products to reduce Escherichia coli and Salmonella typhimurium inoculated on individual bell pepper pieces. Inoculated bell pepper pieces (n = 5) were submerged in sodium hypochlorite, organic acid-based and silver-based product solutions, at the concentration specified in the product label for sanitization of fruits and vegetables. Sodium hypochlorite reduced E. coli and Salmonella typhimurium by 3.13 Log10/25 cm(2) and 2.73 Log10/25 cm(2), respectively. Organic-based and silver-based products reduced E. coli and S. typhimurium by 2.23 Log10/25 cm(2), 1.74 Log10/25 cm(2) and 2.10 Log10/25 cm(2), 1.92 Log10/25 cm(2), respectively. The results showed that greater attention is needed in selecting sanitizing products to kill or remove human pathogens from fresh produce to minimize risk of foodborne infections.

Disinfection alternatives for contact surfaces and toys at child care centers.

Child care surfaces are vehicles for disease-causing organisms. Disinfectant procedures prevent microbial dispersion. This study reports the effectiveness of CITRUS Farm Edition® (CFE), Clorox® GreenWorks™ (CGW) and Clorox® Anywhere® (CA) against Salmonella Typhimurium and Staphylococcus aureus inoculated (1 ml of 9Log(10) CFU/ml) on a high chair and ball toy. Disinfectants were sprayed and bacteria recovered from surfaces by sponge method. Exposing an inoculated high chair to CA resulted in the highest reduction of S. aureus (3.92 Log(10)) and S. Typhimurium (3.22 Log(10)). CGW reduced S. aureus and S. Typhimurium by 2.84 and 2.12 Log(10) from the inoculated high chair, while the inoculated ball toy showed a 2.50 and 1.80 Log(10) reduction, respectively. CFE showed the lowest reduction with 1.42 and 1.53 Log(10) of S. aureus and S. Typhimurium from the inoculated ball toy. CA was the best disinfectant no matter which bacteria or surface was analyzed. Emphasis on the effectiveness of disinfectant products is needed to be included in child care center infection control programs.

Drinking water microbiological survey of the Northwestern State of Sinaloa, Mexico.

A potable water survey, in two important municipalities of the state of Sinaloa, Mexico was conducted. Culiacan, capital city of Sinaloa and its neighboring municipality, Navolato were selected to enumerate Aeromonas hydrophila, Escherichia coli, fecal and total coliforms, Pseudomonas aeruginosa, and Heterotrophic plate count bacteria from 100 households' taps. Manganese; residual chlorine; pH; temperature and turbidity were also examined. Overall, Aeromonas hydrophila was not detected in any of the samples, 3% contained Escherichia coli, 28% had fecal and 46 total coliforms, P. aeruginosa was present in 15% of the samples. HPC bacteria were found in all of the samples but 43% had numbers greater than 500 CFU per ml. The average numbers obtained for the physico-chemical parameters were 0.15 mg/L; 0.32 mg/L; 6.5; 28.7 degrees C and 2.92 NTU for manganese, residual chlorine, pH, temperature and turbidity, respectively. The findings of the current study demonstrate that potable water from both municipalities can harbor substantial numbers of indicator and opportunistic pathogens suggesting that additional treatment in the household may be needed.

Internalization of Salmonella typhimurium into mango pulp and prevention of fruit pulp contamination by chlorine and copper ions.

Outbreaks of Salmonella infections associated with fresh mango consumption have occurred in recent years. The study's objective was to assess the effectiveness of chlorine and copper ions to reduce Salmonella typhimurium from hydro-cooling water and prevent fruit pulp contamination of heat-treated mangos. Mature green Tommy Atkins' mangos were immersed in water at 46.1 degrees C for 100 min. Heat-treated mangos were then introduced, during 30 min, in 25 degrees C water containing 6 Log(10) CFU/ml of Salmonella with or without disinfectants (5 and 8 mg/l of either chlorine or copper ions). Chlorine at 5 and 8 mg/l reduced 6 Log(10) CFU/ml of Salmonella. Copper ions at 5 and 8 mg/l reduced 3.26 and 4.3 Log(10) CFU/ml, respectively. 2 Log(10) of Salmonella penetrated into mango pulp when disinfectants were not applied to 25 degrees C water. Both chlorine and copper ions were effective in preventing fruit pulp contamination by Salmonella typhimurium. Of residual chlorine, 2.37 and 3.54 mg/kg were detected in mango pulp after the treatment of 5 and 8 mg/l, respectively. Copper ions at 5 and 8 mg/l showed a residual content of 0.1 and 0.6 mg/kg on mango pulp, respectively. The chloride and copper residual levels in the pulp did not exceed the daily ingestion rates recommended by the National Academy of Sciences. Salmonella entered mango pulp by vascular elements and lenticels, both natural structures measuring an average diameter of 21 and 112 microm, respectively. The results illustrate the potential for pathogen penetration if heat-treated mangos are cooled in non-disinfected water. Also, appropriate chlorine or copper ion concentration prevents fruit pulp contamination.