Quantitative Microbial Risk Assessment as support for bathing waters profiling

Profiling bathing waters supported by Quantitative Microbial Risk Assessment (QMRA) is key to the WHO's recommendations for the 2020/2021 revision of the European Bathing Water Directive. We developed an areaspecific QMRA model on four pathogens, using fecal indicator concentrations (E. coil, enterococci) for calculating pathogen loads. The predominance of illness was found to be attributable to Human Adenovirus, followed by Salmonella, Vibrio, and Norovirus. Overall, the cumulative illness risk showed a median of around 1 case/10000 exposures. The risk estimates were strongly influenced by the indicators that were used, suggesting the need for a more detailed investigation of the different sources of fecal contamination. Area-specific threshold values for fecal indicators were estimated on a risk-basis by modelling the cumulative risk against E. coll. and enterococci concentrations. To improve bathing waters assessment, we suggest considering source apportionment locally estimating of pathogen/indicator ratios, and calculating site-specific indicators thresholds based on risk assessment

Clostridium perfringens come indicatore di contaminazione ambientale e suo significato sanitario

Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7 , Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Occurrence of Pseudomonas aeruginosa in several sources of drinking water

Introduction Pseudomonas aeruginosa is an environmental ubiquitous bacterium that may cause opportunistic waterborne infections in immunocompromised host. It can be isolated in several aquatic habitat where it shows the ability to survive in a quiescent metabolic state under stressful conditions and to revert to a metabolically active status when environmental conditions allow. In domestic environment it is not rare to find it associated with the water piping system, producing a thick layer of biofilm. Many strains that are biofilm producers express virulence factors and resistances to several antibiotic classes. This study aims to isolate and characterize P. aeruginosa and other Gram-negative bacteria in a range of types of drinking water. Materials and Methods For each water source, 1 liter sample was aseptically collected in sterile flasks containing sodium thiosulfate to neutralize chlorine. The samples were kept at +4 °C and analyzed within 24 hours. Isolation and enumeration of P. aeruginosa was carried out by membrane filtration technique according to the UNI EN ISO 16266: 2008. The isolated strains were identified and tested for antibiotic resistance by Vitek 2 (Biomérieux). All Pseudomonas isolates were tested for biofilm production by violet crystal staining in multiwell 96 plates and their growth was compared to those of strongly producing biofilm reference strains. All strains were stored at -80 ° C for further studies. Results A total of one hundred water samples from different sources was analyzed: tap water, domestic deionizer water (from home filtration devices), water dispensers, ground water and mineral water springs. In most of the samples directly from the drinking water system a microbial load < 10 CFU/L has been detected. In 1/3 of the samples till now analyzed, Gram-negative species, resistant to the chlorine, have been identified. A higher percentage of samples from domestic deionizer and dispenser waters resulted positive for the presence of P. aeruginosa than ground and tap water samples. Discussion and Conclusions Our preliminary data highlight a critical issue related to the home filtration devices installed in the terminal part of taps. Although the water suppliers constantly check the ensuring compliance with the microbial load parameters, the last part of the private pipes frequently hosts microorganisms organized in biofilms mono or multi species able to alter the microbiological quality of water. Deionized water samples have been resulted a large reservoir of microbial diversity. Indeed, the great filtering surface provides perfect substrate to sessile forms triggering the biofilm production and enhancing the growth of bacteria routinely living in drinking water. Further sampling and analysis are necessary to drive reliable conclusions

Microbial Characterization of Water and Biofilms in Drinking Water Distribution Systems at Sport Facilities

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An Italian survey on the microbiological safety of toys containing aqueous media

Aims The purpose of the present investigation is to fill the current gap in information regarding the microbiological quality of toys containing aqueous media and the related risks for users. Methods Over 18 years, a total of 491 sealed toys containing aqueous media were analysed using conventional microbial culture methods. In addition, molecular methods (PCR/nested RT-PCR, followed by Sanger sequencing) were employed to test for enteric viruses (enteroviruses and adenoviruses) in a subset of toys; subsequently, the infectivity of the positive samples was tested on cell cultures. Results Of the examined toys, 23.8% were noncompliant with the limits of the European guideline. The most frequently exceeded limits were those for Aerobic bacteria (84.6%), and Pseudomonas aeruginosa (29.9%). Other opportunistic bacterial species that were frequently detected were Stenotrophomonas maltophilia, Pseudomonas fluorescens, Burkholderia cepacia, Sphingomonas paucimobilis and Comamonas acidovorans. In a subset of 28 samples, adenovirus (25%) and enterovirus (11%) genome was also found to be present, although the samples with viral positivity did not show infectivity after inoculation on appropriate cell monolayers. Conclusions The results indicate a condition of microbial exposure related to the use of toys containing aqueous media. Significance and Impact of Study The investigation highlights the need for more stringent monitoring during the production, packaging and storage of toys containing aqueous matrices in order to safeguard children's health

Microbiological evaluation of open and sealed tattoo inks

Background. Introduction of tattoo inks in the skin has been associated with a potential entry of a great number of microorganisms including bacteria, virus and fungi. Contaminated pigments, diluents and instruments represent primary infection risk factors as well as inadequacy of hygienic measures during this practice. However, the evaluation of the infectious risk for public health due to tattoo ink use is actually not feasible cause of the low efficiency of health surveillance and the lack of specific regulation in this area.Materials and Methods. A survey was carried out to test the microbial product safety of some tattoo inks available in Italian tattoo parlours. Physical packaging and labelling of the collected inks were also examined. Newly acquired sealed stock bottles, open ink bottles and tattoo-correlated instruments (needles, spikes and grips) were collected and tested for different microbiological parameters. Results. Both from opened and sealed inks a variety of potentially pathogenic organisms were isolated and identified including Gram positive rods and cocci, Gram negative bacteria and fungi. Different species of Bacillus and Staphylococcus genera were identified, among which S. haemolyticus; Cronobacter sakazaki, Enterobacter intermedius and Sphingomonas paucimobilis were also identified while no atypical mycobacteria were isolated. Needles, spikes and grips tested for sterility were aseptic.Conclusions. Microbial contamination of opened samples suggest inefficacy of preservatives and additives in maintaining inks hygienic quality, and inadequacy of hygienic procedures during the tattooing operations, while the occurrence of microorganisms in unopened samples put in doubt the effectiveness of the sterilization technology applied to this type of product.</p

Valutazione microbiologica di prodotti di compostaggio: aspetti normativi e igienico-sanitari Procedure operative per lo svolgimento di indagini microbiologiche

Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7 , Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

[World Health Organization (WHO) Guidelines for coastal and fresh waters: Italian translation by the Society of Hygiene, Preventive Medicine and Public Health (SItI) Working Group "Movement Sciences for Health"]

The Working Group "Movement Sciences for Health" of the Italian Society of Hygiene, Preventive Medicine and Public Health has promoted the Italian translation of the WHO Guidelines for Safe Recreational Water Environments, relating to coastal and freshwater environments. In this article the authors briefly summarize the main areas covered in the guidelines, namely drowning and injury, exposure to cold, heat and sunlight, water quality, contamination of beach sand, exposure to algae and their products, aesthetic issues, exposure to chemical and physical agents, dangerous aquatic organisms, monitoring and assessment hazards and risks