scholarly journals Microorganism levels in spray from warm-water bidet toilet seats: factors affecting total viable and heterotrophic plate counts, and examination of the fluctuations and origins of Pseudomonas aeruginosa

2017 ◽  
Vol 16 (3) ◽  
pp. 346-358
Author(s):  
Toru Iyo ◽  
Keiko Asakura ◽  
Makiko Nakano ◽  
Kazuyuki Omae
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Tap Water ◽  
Viable Count ◽  
Warm Water ◽  
Water Heater ◽  
Reservoir Water ◽  
Advantages And Disadvantages ◽  
On Demand ◽  
Plate Counts ◽  
Heterotrophic Plate Counts

Abstract The objectives of this study were to conduct an appropriate microbial evaluation of warm-water bidet toilet seats. Health-related advantages and disadvantages have been associated with using warm-water bidet toilet seats, which are classified according to the tank type, including tanks equipped with reservoir water heaters and on-demand tankless systems equipped with an instantaneous water heater. However, related bacterial research is sparse. Here, we performed a long-term survey of the behavior of microorganisms (i.e., the total viable count (TVC), heterotrophic plate counts (HPCs), and Pseudomonas aeruginosa count) in a university campus. We also examined the differences between the tank and on-demand types, and the origins of P. aeruginosa. A low TVC (≤1/mL) in the spray waters from both on-demand and tank-type warm-water bidet toilet seats showed low bacterial contamination, although there was an increase in HPC, i.e., growth of biofilms, inside in the warm-water bidet toilet seats. When P. aeruginosa was detected in spray water over an extended duration, the P. aeruginosa origin was considered as either from feces or tap water. Collectively our findings demonstrate that hygienic safety of warm-water bidet toilet seats is being maintained overall.

scholarly journals Evaluation of Microbiological and Free-Living Protozoa Contamination in Dental Unit Waterlines

2019 ◽  
Vol 16 (15) ◽  
pp. 2648 ◽  
Author(s):  
Anna Maria Spagnolo ◽  
Marina Sartini ◽  
David Di Cave ◽  
Beatrice Casini ◽  
Benedetta Tuvo ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Tap Water ◽  
Microbiological Quality ◽  
Coliform Bacteria ◽  
Dental Staff ◽  
Plate Counts ◽  
Dental Unit Waterlines ◽  
Heterotrophic Plate Counts

Studies conducted over the last 40 years have demonstrated that the water output from dental unit waterlines (DUWLs) is often contaminated with high densities of microorganisms. It has been monitored the microbiological quality of the water in 30 public dental facilities in northern Italy in order to assess the health risk for patients and dental staff. In each facility, samples of water both from taps and from DUWLs were analyzed in order to evaluate heterotrophic plate counts (HPCs) at 22 °C and 36 °C, and to detect coliform bacteria, Pseudomonas aeruginosa, Legionella pneumophila and amoebae. In 100% of the samples taken from the DUWLs, the concentration of HPCs was above the threshold as determined by the Ministère de la Santé et des Solidarités (2007). The concentration of P. aeruginosa was greater than the indicated threshold in 16.67% of the hand-pieces analyzed. A total of 78.33% of samples were contaminated by L. pneumophila, while in the samples taken from the DUWLs alone, this percentage rose to 86.67%. Amoebae were detected in 60% of the samples taken from hand-pieces; all belonging to the species V. vermiformis. This study documented the presence of various microorganisms, including Legionella spp., at considerably higher concentrations in water samples from DUWLs than in samples of tap water in the same facilities, confirming the role of the internal DUWLs in increasing microbial contamination, especially in the absence of proper management of waterborne health risks.

Evaluation of disinfection processes for water heater devices used for extracorporeal life support

Perfusion ◽  
2019 ◽  
Vol 34 (5) ◽  
pp. 428-432
Author(s):  
Nicole Y R Shrimpton
Keyword(s):  
Heat Transfer ◽  
Life Support ◽  
Extracorporeal Life Support ◽  
Water Heater ◽  
Heating Unit ◽  
Water Filter ◽  
Plate Counts ◽  
Chloramine T ◽  
Heterotrophic Plate Counts ◽  
Water Borne

The Maquet Heater Unit 35 (HU35) is widely used to maintain patient body temperature during extracorporeal life support. Water is used as a medium for heat transfer though it also provides a medium for the growth of pathogens. Thus, the use of a heating unit presents a risk for transmission of water-borne pathogens in critically ill patients. Recently, a Mycobacterium chimaera outbreak in cardiac surgery has been linked to the production of bioaerosols by heater-cooler devices. Consequently, manufacturers have revised cleaning recommendations, with significant impact on staff, budget and environment. Heterotrophic plate counts (HPC) and non-tuberculous mycobacterium growth were assessed following three disinfection processes over a 16-month period. It was found that water quality was acceptable in HU35s when disinfecting with a lower concentration of Chloramine-T than currently recommended, provided exposure of the device to potential pathogens was minimised by the use of a 0.2 μm water filter.

Chlorine requirement for biologically stable drinking water after nanofiltration

2013 ◽  
Vol 14 (3) ◽  
pp. 405-413
Author(s):  
Y. Ohkouchi ◽  
Y. Yata ◽  
R. Bun ◽  
S. Itoh
Keyword(s):  
Drinking Water ◽  
Water Distribution ◽  
Flow Reactor ◽  
Heterotrophic Bacteria ◽  
Tap Water ◽  
Biological Stability ◽  
Bacterial Regrowth ◽  
Chlorine Residual ◽  
Plate Counts ◽  
Heterotrophic Plate Counts

There is considerable interest in minimizing the chlorine residual in Japan's tap water because of increasing consumer complaints about the chlorinous odor of drinking water. However, minimization of the chlorine residual requires stricter control of biodegradable organics in finished water to ensure biological stability during water distribution. In this context, we investigated the improvement of biological stability of drinking water by nanofiltration (NF). The removal of assimilable organic carbon (AOC) was 52% on average, but showed large seasonal variation. It was found to be difficult to maintain the acceptable AOC level for biologically stable water by NF. In addition, significant bacterial regrowth in NF permeates was still observed without chlorination, although 52% AOC was removed. Then, the chlorine concentration required to prevent bacterial regrowth during distribution of nanofiltrated water was determined using continuous-flow reactor systems. The heterotrophic plate counts (HPC) densities in biofilm were monitored at different chlorine conditions. The results indicated that the NF process could significantly reduce the chlorine requirement of the finished water. The relationship between free chlorine residual and HPC in biofilm formed from 1 μgC AOC showed that a trace level of chlorine residual, <0.1 mg/L, could inactivate heterotrophic bacteria and prevent biofilm formation.

scholarly journals Evaluation of Microbiological Quality of Commercially Available Bottled Water in the City of Dhaka, Bangladesh

1970 ◽  
Vol 1 (1) ◽  
pp. 24-30 ◽  
Author(s):  
Ahmad Kamruzzaman Majumder ◽  
KM Nazmul Islam ◽  
Rezwanun Naher Nite ◽  
Rashed Noor
Keyword(s):  
Water Samples ◽  
Tap Water ◽  
Microbiological Quality ◽  
Bottled Water ◽  
Fecal Coliforms ◽  
Plate Counts ◽  
Human Illness ◽  
New Treatment ◽  
Heterotrophic Plate Counts

Bottled water has become one of the most popular drinks in Bangladesh. Now a days it is easily available in the market. Due to lack of confidence on municipal supply water, people now prefer to drink bottled water instead of tap water, mostly when they are outside the home, and in many occasions. In the present study, the presence of total coliforms (TC) and fecal coliforms (FC) from nine commercially available lacal Bangladeshi bottled water samples were examined. The obtained results indicated that most of the studied bottled water were out of their safety guidelines and hence some chronic diseases (renal failure, liver cirrhosis and anemia) are expected in the area understudy, because 68.89% and 31.11% of the bottled water sampled in the current study showed heterotrophic plate counts (HPC) within a range of 1-500 (cfu/ml) and greater than 500 (cfu/ml), respectively and 0% samples showed less than 1 (cfu/ml) in heterotrophic plate counts. The results also revealed the ill performance and poor drinking water quality of the purification systems of the investigated water samples. 28% of the respondents considered that the quality of bottled water was satisfactory, in contrast to the 26% of the respondent, who judged that the quality of bottled water was not that satisfactory. However, the highest (34%) number of the respondents did not know whether the quality of the bottled water is good or not satisfactory. Recommendation was suggested for new treatment systems of the investigated suspicious water to prevent human illness.  DOI: http://dx.doi.org/10.3329/sjm.v1i1.9099Stamford Journal of Microbiology, Vol.1(1), July 2011, p.24-30

Controlling Legionella and Pseudomonas aeruginosa re-growth in therapeutic spas: implementation of physical disinfection treatments, including UV/ultrafiltration, in a respiratory hydrotherapy system

2015 ◽  
Vol 13 (4) ◽  
pp. 996-1005 ◽  
Author(s):  
E. Leoni ◽  
T. Sanna ◽  
F. Zanetti ◽  
L. Dallolio
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Legionella Pneumophila ◽  
Microbiological Quality ◽  
Integrated Treatment ◽  
Environmental Surveillance ◽  
Water Safety ◽  
Water Safety Plan ◽  
Plate Counts ◽  
Physical Treatments ◽  
Heterotrophic Plate Counts

The study aimed to assess the efficacy of an integrated water safety plan (WSP) in controlling Legionella re-growth in a respiratory hydrotherapy system located in a spa centre, supplied with sulphurous water, which was initially colonized by Legionella pneumophila. Heterotrophic plate counts, Pseudomonas aeruginosa, Legionella spp. were detected in water samples taken 6-monthly from the hydrotherapy equipment (main circuit, entry to benches, final outlets). On the basis of the results obtained by the continuous monitoring and the changes in conditions, the original WSP, including physical treatments of water and waterlines, environmental surveillance and microbiological monitoring, was integrated introducing a UV/ultrafiltration system. The integrated treatment applied to the sulphurous water (microfiltration/UV irradiation/ultrafiltration), waterlines (superheated stream) and distal outlets (descaling/disinfection of nebulizers and nasal irrigators), ensured the removal of Legionella spp. and P. aeruginosa and a satisfactory microbiological quality over time. The environmental surveillance was successful in evaluating the hazard and identifying the most suitable preventive strategies to avoid Legionella re-growth. Ultrafiltration is a technology to take into account in the control of microbial contamination of therapeutic spas, since it does not modify the chemical composition of the water, thus allowing it to retain its therapeutic properties.

scholarly journals Optimization of Quantitative Analysis of Biofilm Cell from Pipe Materials

Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1286
Author(s):  
Dorota Papciak ◽  
Andżelika Domoń ◽  
Monika Zdeb ◽  
Agata Skwarczyńska-Wojsa ◽  
Janusz Konkol
Keyword(s):  
Quantitative Analysis ◽  
Tap Water ◽  
Galvanized Steel ◽  
Bacterial Cells ◽  
Supply Networks ◽  
Biofilm Detachment ◽  
Plate Counts ◽  
Microbiological Stability ◽  
Heterotrophic Plate Counts ◽  
Sterile Cotton Swab

The quantitative analysis of biofilm can be used not only to assess the microbiological stability of tap water but also on its basis can assess: the degree of colonization of materials by bacterial cells, the rate of biofilm formation on the surfaces of pipes and determine their composition and number. The article presents the results of research on the development of an effective method of biofilm detachment from the surface of the galvanized steel. The number of biofilm cells was determined by methods: (1) luminometric ATP determination, (2) flow cytometry and (3) heterotrophic plate counts (HPC). The presence of the biofilm was confirmed by SEM and fractal analysis. The analysis of the obtained results showed that the most effective method of detaching the biofilm cells from the galvanized steel surface was the mechanical separation with a sterile cotton swab. The variant with the use of a sterile swab enables rapid collection of the biofilm from the surface of the ducts forming internal installations or water supply networks. Due to the simplicity and speed of obtaining results, the luminometric ATP measurement has been established as the best method for the quantification of biofilm cells. The results of this study were intended to provide reliable and useful data on the quantification of biofilm cells.

Morphological and Physiological Responses of Campylobacter jejuni to Stress

2006 ◽  
Vol 69 (11) ◽  
pp. 2747-2753 ◽  
Author(s):  
PUSSADEE TANGWATCHARIN ◽  
SUGANYA CHANTHACHUM ◽  
PRAPAPORN KHOPAIBOOL ◽  
MANSEL W. GRIFFITHS
Keyword(s):  
Campylobacter Jejuni ◽  
Viable Count ◽  
Cell Suspensions ◽  
Evolutionary Strategy ◽  
Transmission Electron ◽  
Proteomic Study ◽  
Nonculturable Cells ◽  
Plate Counts ◽  
Stressed Cell ◽  
Aging Cell

Under conditions of stress, cells of Campylobacter assume a coccoid shape that may be an evolutionary strategy evolved by the organism to enable survival between hosts. However, the physiology of Campylobacter as it devolves from spiral to coccoid-shaped morphology is poorly understood. In this study, conditions influencing the survival of Campylobacter jejuni ATCC 35921 in broth were determined. Cells in late log phase were resuspended in broth at 4 or 60°C. The culturability of these cold- or heat-stressed cell suspensions was determined by spread plate counts and the activity of cells by the direct viable count technique and 5-cyano-2,3-ditolyltetrazolium chloride staining. C. jejuni changed form completely from culturable to viable but nonculturable cells (VBNC) within 25 days at 4°C, and 15 min at 60°C. Light microscopy of C. jejuni VBNC cells showed that the spiral-shaped cells became coccoid, and transmission electron microscopy of C. jejuni VBNC cells showed that the outer membrane was lost in aging cell suspensions. Furthermore, a limited proteomic study was carried out to compare C. jejuni proteins that exhibited increased or decreased synthesis on exposure to 60°C.

scholarly journals Endotoxin contamination in the dental surgery

2007 ◽  
Vol 56 (9) ◽  
pp. 1230-1234 ◽  
Author(s):  
M. K. Huntington ◽  
J. F. Williams ◽  
C. D. Mackenzie
Keyword(s):  
Bacterial Load ◽  
Dental Surgery ◽  
Paired Samples ◽  
Dental Procedures ◽  
Large Numbers ◽  
Endotoxin Exposure ◽  
Endotoxin Contamination ◽  
Plate Counts ◽  
High Concentrations ◽  
Heterotrophic Plate Counts

Dental waterlines contain large numbers of Gram-negative bacteria. Endotoxin, a component of such organisms, has significant health implications. Paired samples of dental unit water and the aerosols generated during dental procedures were collected, and assayed for bacteria and endotoxin levels, using heterotrophic plate counts and the Limulus amoebocyte lysate test. Consistent with published studies, the extent of bacterial contamination in the dental waters sampled for this investigation surpassed the levels associated with potable water, with counts in excess of 2.0×106 c.f.u. ml−1 in some samples. Correspondingly high concentrations of endotoxin [up to 15 000 endotoxin units (EU) ml−1] were present in the water. A statistically significant Spearman correlation coefficient of ρ=0.94 between endotoxin (EU ml−1) and bacterial load (c.f.u. ml−1) was demonstrated. All of the aerosol samples contained detectable endotoxin. Further studies of the consequences of dental endotoxin exposure, and evaluation of means to prevent exposure, are warranted.

Parameters predictive of Legionella contamination in hot water systems: Association with trace elements and heterotrophic plate counts

2011 ◽  
Vol 45 (6) ◽  
pp. 2315-2321 ◽  
Author(s):  
Annalisa Bargellini ◽  
Isabella Marchesi ◽  
Elena Righi ◽  
Angela Ferrari ◽  
Stefano Cencetti ◽  
...  
Keyword(s):  
Trace Elements ◽  
Water Systems ◽  
Hot Water ◽  
Plate Counts ◽  
Heterotrophic Plate Counts

scholarly journals Taking Screenshots of the Invisible: A Study on Bacterial Contamination of Mobile Phones from University Students of Healthcare Professions in Rome, Italy

2020 ◽  
Vol 8 (7) ◽  
pp. 1075 ◽  
Author(s):  
Domenico Cicciarella Modica ◽  
Massimo Maurici ◽  
Gian Loreto D’Alò ◽  
Cinzia Mozzetti ◽  
Alessandra Messina ◽  
...  
Keyword(s):  
Mobile Phones ◽  
Staphylococcus Epidermidis ◽  
Univariate Analysis ◽  
Clinical Settings ◽  
Linear Regression Models ◽  
Biochemical Tests ◽  
E Coli ◽  
Plate Counts ◽  
Healthcare Professions ◽  
Heterotrophic Plate Counts

Mobile phones (MPs) are commonly used both in the personal and professional life. We assessed microbiological contamination of MPs from 108 students in healthcare professions (HPs), in relation to their demographic characteristics and MPs handling habits, collected by means of a questionnaire. Cultural and biochemical tests were performed, and statistical analyses were carried out. Staphylococci were present in 85% of MPs, Enterococci in 37%, Coliforms in 6.5%; E. coli was never detected. Staphylococcus epidermidis was the most frequently isolated staphylococcal species (72% of MPs), followed by S. capitis (14%), S. saprophyticus, S. warneri, S. xylosus (6%), and by S. aureus (4%). Heterotrophic Plate Counts (HPC) at 37 °C, ranged from 0 to 1.2 × 104 CFU/dm2 (mean = 362 CFU/dm2). In univariate analysis, the male gender only was significantly associated with higher HPCs and enterococcal contamination. Multiple linear regression models explained only 17% and 16% of the HPC 37 °C and staphylococcal load variability, respectively. Developing specific guidelines for a hygienic use of MPs in clinical settings, for preventing cross-infection risks, is advisable, as well as introducing specific training programs to HP students. MPs decontamination procedures could also be implemented in the community.

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