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Journal of the American Association For... Mar 2022Animal care and use programs commonly use chlorine and chlorine-based disinfectants to help prevent facility acquired infections in animals. The Department of...
Animal care and use programs commonly use chlorine and chlorine-based disinfectants to help prevent facility acquired infections in animals. The Department of Comparative Medicine (DCM) at Oregon Health and Science University (OHSU) follows the Centers for Disease Control and Prevention (CDC) disinfection guidelines for preparing and storing these disinfectants. DCM prepares bottles of dilute solutions of sodium hypochlorite (that is, commercial bleach) daily. In this study, we tested whether dilute bleach solutions, as prepared following the DCM protocol, remained stable under real-world practice conditions for up to 6 wk. We tested 4 groups of spray bottles filled with 0.5% bleach solutions in these experiments. Specifically, we sprayed 2 groups of bottles daily to mimic use while 2 other groups of bottles were not sprayed. We then measured free available chlorine (FAC) using 2 methods, spectrophotometry and colorimetric strips. All 4 test groups showed stable maintenance of FAC concentration for the length of the experiment. Mean FAC loss from baseline levels was not significantly different in the group of bottles not sprayed daily (6% for group 2 at week 5 compared with 7% for Group 4 at week 6). All bottles in Groups 1 and 3 measured by colorimetric strips showed concentrations at or near 5000 mg/L at all weekly time points throughout the experiment. This study shows that 0.5% sodium hypochlorite solutions stored and used in a standard rodent housing room and sprayed daily will maintain acceptable FAC concentrations for at least 5 to 6 wk, perhaps longer. In addition, we report that colorimetric strips may be a useful and accessible quality control tool for testing freshly prepared solutions at regular intervals. We conclude that sodium hypochlorite solutions can be prepared on a weekly, biweekly, or monthly basis with no loss in disinfection effectiveness.
Topics: Animals; Chlorine; Disinfectants; Disinfection; Humans; Sodium Hypochlorite
PubMed: 35109965
DOI: 10.30802/AALAS-JAALAS-21-000080 -
American Journal of Infection Control Aug 2022Biofilm formation is a major factor in the resistance mechanism of Klebsiella pneumoniae. This study aimed to evaluate the effects of sodium hypochlorite on the biofilm...
BACKGROUND
Biofilm formation is a major factor in the resistance mechanism of Klebsiella pneumoniae. This study aimed to evaluate the effects of sodium hypochlorite on the biofilm of K. pneumoniae with different drug resistance.
METHODS
We collected 3 different types of K. pneumoniae respectively. The growth trend of biofilms of different drug-resistant K. pneumoniae was quantified by measuring the OD for 7 consecutive days using crystal violet staining. Scanning confocal fluorescence microscopy was used to observe biofilm morphology.
RESULTS
After adding sodium hypochlorite, there were significant differences between the OD value of the 200, 500, and 1,000 µg/mL groups and the positive control group (all P < .05) on the fifth day. Concentrations of 2,000 and 5,000 µg/mL sodium hypochlorite were added after the biofilm had matured. In the 5,000 µg/mL sodium hypochlorite group, the OD of K. pneumoniae biofilm in the 3 groups decreased significantly compared with the blank control group (all P < .05).
CONCLUSIONS
Sodium hypochlorite inhibited and cleared the biofilm of K. pneumoniae with different drug resistance, and the effect was enhanced with the increase of concentration in the range of bacteriostatic and bactericidal concentration.
Topics: Anti-Bacterial Agents; Biofilms; Drug Resistance; Humans; Klebsiella pneumoniae; Microbial Sensitivity Tests; Sodium Hypochlorite
PubMed: 34986390
DOI: 10.1016/j.ajic.2021.12.003 -
Australian Dental Journal Aug 1998Sodium hypochlorite has been used as an endodontic irrigant for more than 70 years, and is now one of the most common solutions for this purpose. The chemical properties... (Comparative Study)
Comparative Study Review
Sodium hypochlorite has been used as an endodontic irrigant for more than 70 years, and is now one of the most common solutions for this purpose. The chemical properties and production of commercial sodium hypochlorite are reviewed. Domestic bleaches and an infant sanitizer are compared from the point of view of cost and ease of use--Milton being recommended where a 1% solution is required. The cost of syringes and needles for endodontic irrigation is many times greater than the hypochlorite they contain, and total annual practice costs for hypochlorite are low. Brief guidelines for clinical use, storage, handling and disposal are included.
Topics: Costs and Cost Analysis; Dental Disinfectants; Household Products; Humans; Root Canal Irrigants; Sodium Hypochlorite
PubMed: 9775472
DOI: 10.1111/j.1834-7819.1998.tb00173.x -
European Endodontic Journal Dec 2020The purpose of this systematic review was to provide the answer to the question: Can sodium hypochlorite and chlorhexidine influence postoperative pain after the...
OBJECTIVE
The purpose of this systematic review was to provide the answer to the question: Can sodium hypochlorite and chlorhexidine influence postoperative pain after the endodontic treatment in necrotic teeth?
METHODS
The PROSPERO registration number is CRD42018096433 and was conducted following the PRISMA statements. The MeSH and free terms were used to search for articles published in the electronic databases (PubMed, Web of Science, Scopus, Cochrane Library, and Virtual Health Library), in the gray literature, and by a manual search. The reviewers selected the studies considering predetermined eligibility criteria, performed data extraction, and evaluated the risk of bias. Only clinical trials comparing the effect of sodium hypochlorite and chlorhexidine on postoperative pain in teeth of adult patients with necrotic pulps were included.
RESULTS
Five studies were qualified for the systematic review. Two studies were considered a low risk of bias. The results showed no statistically significant difference regarding postoperative pain in the groups. Only 1 study reported a statistically significant difference in the sixth postoperative hour, and the pain was associated with the sodium hypochlorite group.
CONCLUSION
There was no influence of auxiliary chemical substance (NaOCl and CHX) on postoperative pain used in endodontic treatment in the teeth with pulp necrosis. However, one study observed a significant difference in the sixth postoperative hour, associated with the sodium hypochlorite group.
Topics: Chlorhexidine; Humans; Pain, Postoperative; Sodium Hypochlorite
PubMed: 33353925
DOI: 10.14744/eej.2020.94830 -
Molecules (Basel, Switzerland) May 2020Numerous substances from different chemical sectors, from the pharmaceutical industry to the many consumer products available for everyday usage, can find their way into...
Numerous substances from different chemical sectors, from the pharmaceutical industry to the many consumer products available for everyday usage, can find their way into water intended for human consumption and wastewater, and can have adverse effects on the environment and human health. Thus, the disinfection process is an essential stage in water and wastewater treatment plants to destroy pathogenic microorganisms but it can form degradation byproducts. Sodium hypochlorite is the most common disinfectant, but the most important drawback associated with this kind of compound is the generation of toxic disinfection byproducts. Many studies have been carried out to identify alternative disinfectants, and in the last few years, peracetic acid has been highlighted as a feasible solution, particularly in wastewater treatment. This study compares the transformations of five emerging pollutants (caffeine, tramadol, irbesartan, diclofenac, trazodone) treated with peracetic acid, to evaluate their degradation and the possible formation of byproducts with those obtained with sodium hypochlorite. Although peracetic acid has many advantages, including a wide field of use against microorganisms and a low toxicity towards animal and plant organisms, it is not as effective in the degradation of the considered pollutants. These ones are recovered substantially and are unchanged quantitatively, producing a very low number of byproducts.
Topics: Peracetic Acid; Pharmaceutical Preparations; Sodium Hypochlorite; Wastewater; Water Purification
PubMed: 32414067
DOI: 10.3390/molecules25102294 -
European Endodontic Journal Dec 2020To assess the effect of osmotic stress on various bacteria in a planktonic milieu and the effect of exposure to sodium hypochlorite (NaOCl) on the microbial cells...
OBJECTIVE
To assess the effect of osmotic stress on various bacteria in a planktonic milieu and the effect of exposure to sodium hypochlorite (NaOCl) on the microbial cells previously subjected to osmotic stress.
METHODS
Enterococcus faecalis, Streptococcus sanguinis, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia were suspended as follows: Iso-osmotic group 0.9% NaCl; Hypo-osmotic group "ultrapure water"; Hyper-osmotic group 9% NaCl solution for 120 hours before exposure to 0.0001% NaOCl for 10 minutes. Quantitative analyses of viable cells were performed at 0 and 120 hours and after exposure to NaOCl to obtain colony forming units (CFU/mL). A linear mixed-effects model was used to find the association between mean CFU/mL (logarithmic transformation) and the interaction of solution Group and Time (P<0.001).
RESULTS
F. nucleatum, P. gingivalis and P. intermedia did not survive after 24 hours in any of the solutions and were excluded from further testing. For S. sanguinis there were significant differences at each time interval, when holding solution group constant. After 120 hours, the Hyper-osmotic group presented with the highest CFU/mL and was significantly different to the Iso-osmotic group (P<0.001). For E. Faecalis, there was a significant difference for each pairwise comparison of time (P<0.001) in mean CFU/mL between 0 hours and 120 hours for the Iso-osmotic and Hyper-osmotic groups. At 120 hours, no significant differences were found between the three groups. Significant differences were also found between 0 hours and Post-NaOCl administration, and between 120 hours and Post-NaOCl administration for all three groups (P<0.001). Exposure to NaOCl after hypo-osmotic stress was associated with significantly less CFU/mL for S. sanguinis compared to hyperosmosis and iso-osmosis (P<0.001) and for E. Faecalis only compared to hyperosmosis (P<0.001).
CONCLUSION
S. sanguinis and E. faecalis were able to withstand osmotic stress for 120 hours. Hypo-osmotic stress before contact with NaOCl was associated with lower viable bacterial numbers, when compared to the other media for the above species. Hyper-osmotic stress was associated with higher viable bacterial numbers after NaOCl exposure for E. faecalis.
Topics: Enterococcus faecalis; Microbiota; Osmotic Pressure; Root Canal Irrigants; Sodium Hypochlorite
PubMed: 33353919
DOI: 10.14744/eej.2020.70883 -
Journal of Bacteriology Oct 2012The ability to maintain intracellular concentrations of toxic reactive oxygen species (ROS) within safe limits is essential for all aerobic life forms. In bacteria, as... (Review)
Review
The ability to maintain intracellular concentrations of toxic reactive oxygen species (ROS) within safe limits is essential for all aerobic life forms. In bacteria, as well as other organisms, ROS are produced during the normal course of aerobic metabolism, necessitating the constitutive expression of ROS scavenging systems. However, bacteria can also experience transient high-level exposure to ROS derived either from external sources, such as the host defense response, or as a secondary effect of other seemingly unrelated environmental stresses. Consequently, transcriptional regulators have evolved to sense the levels of ROS and coordinate the appropriate oxidative stress response. Three well-studied examples of these are the peroxide responsive regulators OxyR, PerR, and OhrR. OxyR and PerR are sensors of primarily H(2)O(2), while OhrR senses organic peroxide (ROOH) and sodium hypochlorite (NaOCl). OxyR and OhrR sense oxidants by means of the reversible oxidation of specific cysteine residues. In contrast, PerR senses H(2)O(2) via the Fe-catalyzed oxidation of histidine residues. These transcription regulators also influence complex biological phenomena, such as biofilm formation, the evasion of host immune responses, and antibiotic resistance via the direct regulation of specific proteins.
Topics: Bacteria; Cysteine; Gene Expression Regulation, Bacterial; Histidine; Oxidation-Reduction; Oxidative Stress; Peroxides; Reactive Oxygen Species; Sodium Hypochlorite; Stress, Physiological; Transcription Factors
PubMed: 22797754
DOI: 10.1128/JB.00304-12 -
PeerJ 2022Dental impressions are used to record anatomy of teeth and surrounding oral structures. Impression materials become contaminated with saliva and blood requiring...
BACKGROUND
Dental impressions are used to record anatomy of teeth and surrounding oral structures. Impression materials become contaminated with saliva and blood requiring disinfection, which may have negative impact on dimensional stability of materials.
OBJECTIVE
Comparatively evaluate linear dimensional changes of synthesized Tetra-functional (dimethylsilyl) orthosilicate (TFDMOS) containing Polyvinylsiloxane (PVS) impressions following sodium hypochlorite disinfection.
METHODS
Percentage dimensional changes of three commercial PVS (Elite HD Monophase, Extrude and Aquasil Ultra Monophase) and five experimental PVS impression materials were measured. Experimental material contained novel cross-linking agent (TFDMOS) and a non-ionic surfactant (Rhodasurf CET-2) that is Exp-A (without TFDMOS), Exp-B (with TFDMOS), Exp-C (TFDMOS+ 2% Rhodasurf CET-2), Exp-D (TFDMOS+ 2.5% Rhodasurf CET-2) Exp-E (TFDMOS+ 3% Rhodasurf CET-2). Samples were made using rectangular stainless-steel molds (40 × 10 × 3 mm) and linear dimensional changes were measured using a calibrated travelling microscope at 10× magnification after immersion in distilled water (D.W) and 1% Sodium Hypochlorite solution at two different time intervals ., 30 min and 24 h.
RESULTS
Samples immersed in 1% NaOCl showed significant ( < 0.05) dimensional changes after 30 min of immersion. Exp-E showed significantly greater dimensional changes than their control (Exp-A and Exp-B). In distilled water, there were no significant difference among the tested materials. Aquasil exhibited highest expansion (0.06%) in both solutions. At 24 h, among the commercial materials, Extrude had the greatest expansion followed by Aquasil and Elite in DW while Aquasil showed the greatest expansion followed by Extrude and Elite in NaOCl.
CONCLUSION
Experimental PVS had linear dimensional changes within the ISO 4823; 2015 recommended range. However, extended immersion can negatively affect the linear dimensions.
Topics: Sodium Hypochlorite; Disinfection; Water
PubMed: 35174015
DOI: 10.7717/peerj.12812 -
International Endodontic Journal Aug 2019To test whether the incorporation of a chelation powder, etidronate, marketed for root canal irrigation (Dual Rinse HEDP) into a sodium hypochlorite (NaOCl) solution...
AIM
To test whether the incorporation of a chelation powder, etidronate, marketed for root canal irrigation (Dual Rinse HEDP) into a sodium hypochlorite (NaOCl) solution induced additional cytotoxic and genotoxic effects not observed with NaOCl alone.
METHODOLOGY
Fresh and 24-h-old mixtures of 0.9 g of etidronate in 10 mL of 2.5% NaOCl were assessed for their basic chemical features including pH and the ability to chelate Ca from hydroxylapatite. Pure NaOCl and phosphate-buffered saline (PBS) with/without etidronate served as control solutions. Cytotoxic and genotoxic effects of diluted solutions (1:10, 1:100, and 1:1000) were assessed on Chinese hamster lung fibroblast (V79) using the MTT, clonogenic and micronucleus assays, respectively. One-way ANOVA and Tukey's HSD test were applied with an alpha-type error of 5% (P < 0.05).
RESULTS
In mixtures of NaOCl and etidronate, the free available chlorine was lost completely after 24 h, and the pH dropped by more than 3 units. However, the ability of the etidronate to chelate Ca was maintained. The fresh mixtures of NaOCl and etidronate were not more toxic than NaOCl alone (P > 0.05), whilst the 24-h-old mixtures were less toxic (P < 0.05) and statistically similar to pure etidronate. Etidronate per se showed little cytotoxicity and no genotoxicity at the tested dilutions.
CONCLUSIONS
The ability of the used etidronate, Dual Rinse HEDP, to chelate calcium is not affected by NaOCl. Cytotoxicity and genotoxicity of mixed solutions is dictated by the presence of free available chlorine therein.
Topics: Chelating Agents; DNA Damage; Etidronic Acid; Root Canal Irrigants; Root Canal Therapy; Sodium Hypochlorite
PubMed: 30848496
DOI: 10.1111/iej.13110 -
International Journal of Environmental... Oct 2019Chemical reaction of main polymer and additive with oxidative cleaning agents plays an important role in aging of polymeric membrane for water and wastewater treatment....
Chemical reaction of main polymer and additive with oxidative cleaning agents plays an important role in aging of polymeric membrane for water and wastewater treatment. As a green and powerful oxidant, hydrogen peroxide (HO) can achieve good cleaning efficacy under alkaline condition, but its influence on membrane aging was poorly understood. In this study, degradation of polyethersulfone (PES) membrane due to HO exposure under alkaline condition (pH 9 and 11) was holistically investigated by humic acid (HA) filtration experiments and multiple membrane characterization techniques, with sodium hypochlorite (NaClO) aging examined as a comparison. Membrane permeability and HA retention rate was hardly changed by HO aging at an exposure dose of 500 g·h/L, whereas NaClO aging led to substantial increase of membrane permeability and significant decrease of retention ability. Meanwhile, HO aging slightly increased fouling propensity with HA filtration, while NaClO aging resulted in more serious fouling. ATR-FTIR and XPS analysis revealed much less degradation of PES and hydrophilic additive by HO than that by NaClO, and membrane morphology and surface properties were characterized to explain the variation of filtration performance. Overall, compared with cleaning with NaClO, membrane degradation can be minimized by cleaning with HO.
Topics: Humic Substances; Hydrogen Peroxide; Hydrophobic and Hydrophilic Interactions; Membranes, Artificial; Polymers; Sodium Hypochlorite; Sulfones; Ultrafiltration
PubMed: 31635217
DOI: 10.3390/ijerph16203972