sodium-hypochlorite and potassium-hydroxide

Although ingestion of alkali-based and/or hypochlorite-based household cleaners as well as strong acids remains a major cause of esophageal wall injury, little is known about the mechanisms that underlie the injury response to these toxic agents. This study examined the roles of vascular dysfunction and inflammation to the esophageal injury response to different caustic substances in mice.. The esophageal responses to sodium hydroxide (10%, 5%, and 2.5%), potassium hydroxide (10%, 5%, and 2.5%), sodium hypochlorite (5.25%), and hydrochloric acid (10%, pH 2) were evaluated by intravital videomicroscopy and histopathology. Intravital microscopy was used to monitor changes in the diameter of arterioles and venules, the adhesion and movement of leukocytes in venules, and the time of cessation of arteriolar blood flow in mouse esophagus. The esophageal mucosa was exposed to caustic substances for 0 to 60 minutes before evaluation.. The higher concentrations of sodium hydroxide and potassium hydroxide elicited rapid stasis in both arterioles and venules, which was accompanied by arteriolar constriction and thrombosis. An accumulation of adherent leukocytes in venules was not observed with any agent. Histopathological evaluation revealed marked cellular and interstitial edema in the mucosa with alkali, whereas hydrochloric acid and sodium hypochlorite decreased the thickness epithelial layer.. These findings suggest that ischemia and thrombosis are dominant processes, whereas inflammation is less important in the pathogenesis of acute corrosive injury to the esophageal mucosa.

Topics: Animals; Caustics; Esophagus; Hydrochloric Acid; Hydroxides; Male; Mice; Mice, Inbred C57BL; Microcirculation; Potassium Compounds; Sodium Hydroxide; Sodium Hypochlorite

Salmonella Enteritidis infections of egg contents can be related to external contamination of the shell. In this study, the efficacy of three commercial cleaning and/or sanitizing compounds (sodium carbonate, sodium hypochlorite, and potassium hydroxide) was evaluated for bactericidal activity at pH values of 10, 11, and 12 against various concentrations (10(2), 10(4), or 10(6) CFU/ml) of Salmonella Enteritidis inoculated onto the eggshell surface. Efficacy of these chemical agents was also assessed against Salmonella Enteritidis in aqueous suspension. Our results indicated that none of the chemicals applied at the recommended manufacturer's concentrations (sodium carbonate, 36 ppm; other treatments, 200 ppm) could eliminate Salmonella Enteritidis from eggshells artificially contaminated with the highest bacterial concentrations (10(4) or 10(6) CFU/ml). Higher concentrations of each product, at least 5 to 20 times greater than recommended doses, were needed to destroy the bacteria on egg surfaces. However, at or slightly above the manufacturer's recommended use concentrations, all three formulations were effective against Salmonella Enteritidis in aqueous suspension (10(8) CFU/ml) or on eggshells contaminated with 10(2) CFU/ml. For both shell and suspension assays, inactivation of Salmonella Enteritidis occurred at lower concentrations at pH 12 than at pH 11 and 10. Contact time between chemicals and Salmonella apparently influenced bacterial inactivation. Extended contact times (2 to 10 min) reduced minimum chemical concentrations necessary to inactivate the bacteria. However, neither pH nor contact time influenced Salmonella Enteritidis inactivation when the initial bacterial numbers on eggshells were high.

Topics: Animals; Carbonates; Chickens; Colony Count, Microbial; Disinfectants; Dose-Response Relationship, Drug; Egg Shell; Food Contamination; Food Microbiology; Hydrogen-Ion Concentration; Hydroxides; Potassium Compounds; Salmonella enteritidis; Sodium Hypochlorite; Time Factors

The present study was designed to evaluate and compare the corrosion rates of the stainless-steel endodontic files when immersed in 0.2% chlorhexidine gluconate, 5.25% NaOCl, chlorinated soda with KOH, and 17% EDTA irrigating solutions.. Corrosion rates of stainless-steel K-files in irrigating solutions were determined electrochemically by the Tafel extrapolation method. The cutting flutes of files were immersed in solutions and used as an electrode. A saturated calomel electrode (SCE) was used as a reference, and a platinum plate was used as a counter electrode. In order to determine corrosion rates, the linear part of anodic currents obtained from electrochemical current-potential curves, was extrapolated to corrosion potentials.. The corrosion rates of stainless-steel files in the tested solutions from the highest to the lowest were: 0.2% chlorhexidine gluconate>5.25% NaOCl>chlorinated soda with KOH>17% EDTA. The differences between the corrosion rates of files were not found to be statistically different for chlorinated soda with KOH and EDTA (P >0.05), but statistically significant differences were found amongst other groups.. The results of the present study indicated that 0.2% chlorhexidine gluconate, 5.25% NaOCl and chlorinated soda with KOH cause severe corrosion on the surface of selected stainless-steel files.

Topics: Analysis of Variance; Chlorhexidine; Corrosion; Dental Alloys; Dental Instruments; Edetic Acid; Electrochemistry; Hydroxides; Microscopy, Electron, Scanning; Potassium Compounds; Root Canal Irrigants; Root Canal Preparation; Sodium Bicarbonate; Sodium Hypochlorite; Stainless Steel; Surface Properties

We compared three sodium hypochlorite digestion methods and two potassium hydroxide digestion methods for detection of ferruginous bodies in human tissues. The following results were obtained. 1. Methods using sodium hypochlorite were effective for digestion of lung tissue samples, but only in part for greater omentum tissue samples. The potassium hydroxide digestion method worked well for preparation of lung and greater omentum tissue samples. 2. Results obtained by the different digestion methods were compared by Kruskal-Wallis test and Mann-Whitney U-test. No significant difference was detected in concentrations of ferruginous bodies and naked fibers in samples of lung, and tumor and normal tissues of the greater omentum among the digestion methods. 3. A more simplified procedure for sample processing with potassium hydroxide digestion was recommended for detection of ferruginous bodies in human tissues.

Topics: Humans; Hydroxides; Iron; Lung; Male; Mesothelioma; Middle Aged; Omentum; Peritoneal Neoplasms; Potassium; Potassium Compounds; Sodium Hypochlorite