Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “DISINFECTANTS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed2004

Application of a high-level peracetic acid disinfection protocol to re-process antibiotic disinfected skin allografts.

Skin allografts, derived from cadaveric donors, are widely used for the treatment of burns and ulcers. Prior to use in clinical situations, these allografts are disinfected using a cocktail of antibiotics and then cryopreserved. Unfortunately, this antibiotic disinfection procedure fails to decontaminate a significant proportion and these contaminated grafts can not be used clinically. We have investigated whether it is possible to apply a second, more potent disinfection procedure to these contaminated grafts and effectively to re-process them for clinical use. Cadaveric skin grafts, treated with antibiotics and cryopreserved, were thawed and a peracetic acid (PAA) disinfection protocol applied. The grafts were then preserved in a high concentration of glycerol or propylene glycol, and properties thought to be essential for successful clinical performance assessed. The cytotoxicity of the grafts was assessed using both extract and contact assays; damage to the skin collagen was assessed using a collagenase susceptibility assay and the capacity of the grafts to elicit an inflammatory response in vitro was assessed by quantifying the production of the pro-inflammatory cytokine TNF-alpha by human peripheral blood mononuclear phagocytes. PAA disinfection, in conjunction with either glycerol or propylene glycol preservation, did not render the grafts cytotoxic, pro-inflammatory, or increase their susceptibility to collagenase digestion. The rates of penetration of glycerol and propylene glycol into the re-processed skin were comparable to those of fresh skin. This study has demonstrated that PAA disinfection combined with immersion in high concentrations of either glycerol or propylene glycol was an effective method for re-processing contaminated skin allografts, and may justify their clinical use.

Anti-Bacterial Agents↗
PubMed2000

A bacteriological study of hospital beds before and after disinfection with phenolic disinfectant.

In hospitals, one of the ways to control microbial contamination is by disinfecting the furniture used by patients. This study's main objective was to evaluate the microbiological condition of hospital mattresses before and after such disinfection, in order to identify bacteria that are epidemiologically important in nosocomial infection, such as Staphylococcus aureus and Pseudomonas aeruginosa. RODAC plates with two different culture media were used to collect specimens. Patient beds were selected according to previously established criteria, and surface areas on the mattresses were chosen at random. From the total of 1,040 plate cultures from 52 mattresses, positive results were obtained from 500 of them (48.1%), 263 before disinfection and 237 after disinfection. Considering the selectivity of the culture media, the positivity rate was high. There were high prevalences of S. aureus both before and after mattress disinfection. The study results suggest that the usual disinfection procedures, instead of diminishing the number of microbes, merely displace them from one part of the mattress to another, and the number of microorganisms remains the same.

Bacteria↗
PubMedDate not supplied

Disinfection of wastewater by hydrogen peroxide or peracetic acid: development of procedures for measurement of residual disinfectant and application to a physicochemically treated municipal effluent.

The Montreal Urban Community Wastewater Treatment Plant (MUCWTP) located in Montreal. Quebec, Canada, uses physicochemical treatment processes prior to discharging wastewater into the St. Lawrence River via an outfall tunnel of 2 hours retention time. Although chlorination facilities exist, they are not being used, and the MUCWTP is seeking alternative methods for disinfection to achieve a 2- to 3-log fecal coliform reduction. Liquid chemical disinfectants were attractive options because of their low capital costs. This led to an investigation of the feasibility of using hydrogen peroxide or peracetic acid. A method for measuring peroxycompounds (hydrogen peroxide or peracetic acid plus hydrogen peroxide) was developed using the peroxidase-based oxidation of 2,2'-azino-bis(3-ethylbenz-thiazoline-6-sulfuric acid) diammonium salt (ABTS) with hydrogen peroxide. The validity of the method was confirmed using effluent from the MUCWTP. Recovery was higher than 90% for peracetic acid levels as low as 1.0 mg/L. Quenching of hydrogen peroxide was achieved with 50-mg/L catalase; quenching of peracetic acid was achieved with 100 mg/L of sodium thiosulfate, followed by 50 mg/L of catalase. Batch disinfection tests were conducted on MUCWTP effluent. Hydrogen peroxide and peracetic acid in wastewater over time could be modeled as a second-order decay, with the decay "constant" being a function of the initial concentration of peroxycompounds. This function was the same for both hydrogen peroxide and peracetic acid, possibly indicating similar decomposition pathways in wastewater matrices. Disinfection was modeled using a modified Hom equation. Required doses of hydrogen peroxide to reach the target fecal coliform levels ranged from 106 to 285 mg/L, with the higher doses occurring when ferric chloride instead of alum was used as the coagulant. Hence, hydrogen peroxide was infeasible as a disinfectant for this application. On the other hand, the peracetic acid dose needed to achieve the target fecal coliform level was only 0.6 to 1.6 mg/L. Therefore, peracetic acid seems to be a promising disinfectant for physicochemical or primary effluent, or combined sewer overflows.

Algorithms↗
PubMed1975

[Critical assessment of methods for testing chemical disinfectants and disinfection procedures (author's transl)].

Since the earliest days of disinfectant testing two different methods have to be distinguished: one group simulating practical circumstances the other one allowing the determination of germ reduction, disregarding any practical conditions. At present the assessment of disinfectant substances is carried out according to the results of several methods, done in different countries. Usually standardised suspension-tests with no correspondance to-in-use conditions are done. These are for example the determination of the Rideal-Walker and the Chick Martin coefficient and the capacity test by Kelsey and Sykes as well. Results obtained by the use-dilution method (A.O.A.C.) are also just of theoretical value. The British Standard-Test 3286:1960 and the suspension-test of the Committee on Phytopharmacy (Netherlands), to be preferred in order to state germ reductions, do not imitate particulars of practice either. After establishing recommendations for the various disinfectant procedures, the unification of the test methods on international level should be the next aim. Besides evaluation of disinfectant substances (as it is done by suspension-tests) the testing of disinfectant procedures under conditions, copying those of real life ought to be required. The results of such in-use model tests should answer all the questions arising, for instance, what the concentrations or the exposure-time should be. We would plead in favour of testing disinfectant substances and procedures in two steps - preliminary testing and main tests under in-use conditions for each new preparation. The base for all these tests is the selection of a suitable inactivator.

Disinfectants↗
PubMed1997

[The observation on the disinfecting efficiency of the disinfectant 93].

Disinfectant 93 is a colorless and transparent liquid. It contains surfactant and hand-protective. Its major component is Di(octyl amino-ethyl) glycine hydrochloride. 99.8% natural bacteria could be removed from the medical staff's hands by using the disinfectant 93 to scrub for 1 min twice. According to the standard of the Ministry of Public Health, it is allowed that the amount of bacteria on the hands is less than equal to 10cfu/cm2 under the condition of class III, and less than equal to 5cfu/cm2 under the condition of class I [symbol: see text] II, in which the qualification rate reached to 100% and 98%, respectively. The average elimination rate of natural bacteria reached to 99.5% and 99.3%, when the hands of surgical operators were disinfected with the disinfectant 93 after scrubbing and brushing with soap. The results showed that disinfecting efficiency of the disinfectant 93 was stronger, its continued effects were also visible, and it wasn't irritative for skin.

Colony Count, Microbial↗
PubMed2005

Disinfection of endoscopes from Helicobacter pylori-positive subjects: evaluation of the effectiveness of the Chinese Calijing disinfection kit.

BACKGROUND: The aim of this study was to evaluate the effectiveness of the Calijing disinfection kit (an endoscope disinfection method used in Chinese hospitals) in eradicating Helicobacter pylori and assess whether use of the kit in 1994 during endoscopies in the Shandong Intervention Trial (SIT), Shandong, China, could have resulted in iatrogenic transmission of H pylori . METHODS: Bacterial culture studies at the Veterans Affairs Medical Center, Houston, Texas, using endoscopes and forceps from 49 H pylori -positive patients were performed on contaminated endoscopes before and after disinfection with the Calijing kit. RESULTS: At least 1 endoscope culture site was H pylori positive in 39 of 49 (79.6%) specimens predisinfection, whereas H pylori was not isolated from any endoscopic culture site postdisinfection. Non- H pylori bacteria and fungi were recovered from 22.6% of the postdisinfection cultures. CONCLUSION: Although no viable H pylori were recovered following the disinfection procedures, levels of H pylori below the detection threshold of the bacteriologic assay may have contributed to an increase in H pylori seroprevalence noted in the SIT. In addition, the kit was unable to provide disinfection against non- H pylori organisms, suggesting the need to adhere to internationally accepted disinfection procedures for endoscope reprocessing.

Cross Infection↗
PubMed1991

Disinfection of fiberscopes by thermochemical disinfection.

A new fully automated washing and disinfection machine for fiberscopes was evaluated. This apparatus, the Endoscopic Thermo Disinfector (ETD) uses a combination of heat and a brand name disinfectant containing glutaraldehyde to fulfill its purposes. The disinfectant showed effective antibacterial activity at the concentrations used in the ETD. After artificial contamination of fiberscopes with high concentrations of various bacteria the washing and disinfection process was completely effective. Contaminated debris was also effectively removed from fiberscopes and from the inside of the washing machine during this process. A number of improvements in the design of the washing machine were implemented during the test period and suggestions for further improvements will be considered. Taking into consideration the reported effects of the disinfectant used against viral pathogens, the ETD washing machine effectively cleans and disinfects flexible watertight endoscopes.

Disinfection↗
PubMed2000

[Virucidal activity of disinfectants: virucidal activities of disinfectants on some viruses coated on several materials and its durability].

First, four disinfectants were tested for virucidal activity on viruses coated upon materials. Disinfectants of the aldehyde and halogen groups had a destructive effect on both enveloped and non-enveloped DNA and RNA viruses coated on a cotton gauze, stainless chips, wood shavings, polyplopylene resin chips and latex resin chips, respectively. Disinfectant of the biguanide group had a virucidal activity on both enveloped DNA and RNA viruses. Secondary, five disinfectants were tested for the durability of their virucidal activity on two DNA and RNA viruses after preparing working solutions. The disinfectants of the aldehyde group maintained their virucidal efficiency for 2 to 3 days. Disinfectants of the invert and amphoteric soap groups, the biguanide group and the halogen group maintained their virucidal efficiency for 1 to 2 days. In the presence of bovine serum, the virucidal activity of the aldehyde group and the halogen group were not influenced but that of the invert and amphoteric soap groups were strongly influenced and lost their effect.

Adenoviruses, Human↗
PubMed2004

Effectiveness of various chemical disinfectants versus cleaning combined with heat disinfection on Pseudomonas biofilm in hemodialysis machines.

The development of bacterial biofilms in the hydraulic circuit of hemodialysis machines is routinely prevented by frequent use of a variety of chemical and heat disinfection strategies. This study compared the effectiveness of several chemical disinfectants, commonly used either alone or in combination with a treatment regimen that involved cleaning plus heat disinfection using an in vitro Pseudomonas biofilm model. Effectiveness of these procedures was evaluated using total and viable biomass quantitation and polysaccharide and endotoxin determination. The chemical disinfection procedures were only partially successful in removing all biofilm components. Heat disinfection alone killed viable biofilm bacteria, but did not remove all the biomass components, including endotoxin. The combination of cleaning with citric acid followed by heat disinfection was the most effective in eliminating all biofilm components from the hydraulic circuit of the in vitro model.

Biofilms↗
PubMed1975

[Testing a disinfectant used for chemothermic disinfection (author's transl)].

Experiments were carried out to test the bacteriological effectiveness of an aldehyde-based disinfectant used for the chemothermic disinfection of instruments. The product is designed to be added to instrument washing machines whereby the temperature should be 65 degrees C. The death rate by means of heat (65 degrees C) of 4 different species of bacteria (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris), which were all suspended in four different media, was determined. E. coli proved to be the most thermoresistant. It was not possible to destroy all the bacteria within one hour. The disinfectant alone was also not sufficient. The suspension, the instrument-disinfection- and the carrier-tests were based upon the "DGHM-Richtlinien". They were, however, carried out in the water bath at 65 degrees C so that the influence of the temperature and the disinfectant could be determined simultaneously. Good results were obtained with this combination of heat and disinfectant. Fungi and mycobacteria were also destroyed.

Bacteria↗
PubMed1995

[Contamination of flexible fiberoptic bronchoscopes with Mycobacterium chelonae linked to an automated endoscope disinfection machine--on the relationship between the presence of the organism in the intestinal tract and contamination of disinfection machine, and a case of gallbladder and bile duct infection with M. chelonae].

In 1993, thirteen strains (8.7%) of M. chelonae were isolated from bronchoalveolar lavage fluid (BALF) obtained by bronchoscopy of 150 patients in Tachikawa-sogo (T) hospital, where the same automated disinfection machine was commonly used for cleaning, sterilization and disinfection of fiberbronchoscope and fibercolonoscope except 3 bronchoscopes disinfected by gas sterilization. Since January 1994, manual cleaning and sterilization has been applied for bronchoscope, and thereafter no strain of M. chelonae was isolated from BALF of 55 patients in the T hospital. While only one strain (3%) of M. chelonae was isolated from BALF of 33 patients in Ota (O) hospital, but many strains of M. chelonae were isolated from intestinal fluid obtained by fibercolonoscopy of the patients. Manual method of cleaning and disinfection was performed for both bronchoscopes and colonoscopes in the O hospital from the beginning. Based on these results, it was suggested that M. chelonae are commonly present in the colon (intestine) of normal persons. Thus colonoendscope may be often contaminated with the organism and subsequently the automated disinfecting machine may also be contaminated with the organism which is resist and against usual disinfection procedure, and resulted in bronchoscope contamination. If the presence of M. chelonae in intestinal tract is not rare, bile duct may be naturally infected with the organism. A case of cholecystitis and cholangitis caused by M. chelonae, which has not been reported previously, was found in the T hospital.

Aged↗
PubMed1996

Comparative disinfectant efficacy of two disinfecting solutions against Pseudomonas aeruginosa.

PURPOSE: We compared the disinfecting efficacy of Pure Eyes Disinfectant and Opti-Free Rinsing, Disinfecting and Storage Solution, without recommended daily cleaning steps, against Pseudomonas aeruginosa. METHODS: Vifilcon A soft contact lenses were inoculated with the challenge organism, P. aeruginosa ATCC 15442, at a concentration of 1 x 10(8) colony forming units (CFU/mL) and disinfected with each solution for four and six hours, respectively. RESULTS: Pure Eyes eradicated P. aeruginosa after both four and six hour soak times. With all lots of Opti-Free, colony forming units were too numerous to count (> 200) for both soak times. CONCLUSIONS: We concluded that, because Pure Eyes disinfecting solutions can eradicate P. aeruginosa without the benefit of a daily cleaning step, this disinfecting process may offer protective benefits to noncompliant contact lens wearers.

Colony-Forming Units Assay↗
PubMed1991

D-value determinations are an inappropriate measure of disinfecting activity of common contact lens disinfecting solutions.

Determination of a D value for specific test organisms is a component of the efficacy evaluation of new contact lens disinfecting solutions. This parameter is commonly defined as the time required for the number of surviving microorganisms to decrease 1 logarithmic unit. The assumption made in establishing a D value is that the rate of kill exhibits first-order kinetics under the specified conditions. Such exponential kill rates are seen with thermal contact lens disinfection system. A comparison of the death rate kinetics for a variety of chemical contact lens disinfecting solutions was undertaken to ascertain the suitability of D-value determination for these chemical disinfectants. The active agents of these different solutions included hydrogen peroxide, thimerosal, chlorhexidine, tris(2-hydroxyethyl)tallow ammonium chloride, thimerosal, polyaminopropyl biguanide, and polyquaternium-1. The solutions were challenged with 10(6) CFU of either Pseudomonas aeruginosa, Serratia marcescens, or Staphylococcus hominis per ml, and survival rate was determined. This study clearly demonstrates the nonlinear nature of the inactivation curves for most contact lens chemical disinfecting solutions for the challenge organisms. D-value determination is, therefore, an inappropriate method of reporting the biocidal activity of these solutions.

Contact Lenses↗
PubMed1988

Cleaning and disinfectant properties of dental surface disinfectants.

The appropriate use of disinfectants for operatory surfaces constitutes a major component of a routine infection control protocol. Both the cleaning and the disinfection abilities of the various available products are important to consider when selecting a surface disinfectant. This study shows the importance of initial surface cleaning as a mandatory first step in surface asepsis. All manufacturers emphasize this in their written directions by stating that the products should be used on precleaned surfaces. Based on the inability to remove dried organic material and a lack of effective antimicrobial activity in the presence of accumulated bioburden, preparations containing high concentrations of alcohols (greater than or equal to 70%) should not be used as the sole agent for routine precleaning and disinfection. Properly diluted iodophor, sodium hypochlorite, and complex phenol preparations are superior in comparison with other disinfectants in accomplishing the initial precleaning of surfaces.

Communicable Disease Control↗
PubMed1993

Determining health risks associated with disinfectants and disinfection by-products: research needs.

In order to minimize the levels of potentially toxic disinfectants and disinfection by-products in treated water while maintaining adequate protection against microbiological contamination, the total risks associated with disinfection have to be measured and compared with the risks from microbial agents. Because much work has already been carried out on chlorination and its by-products, it is recommended that research focus on major disinfection alternatives, i.e., ozonation, chloramination, carbon dioxidation, and the most practical combinations of these options. The primary research needs are (1) assessment of the relative toxicological hazards of the disinfectants and their by-products and (2) development of biologically based models for the dose-response relationships of these chemicals.

Animals↗
PubMed2005

Genotoxicity of the disinfection by-products resulting from peracetic acid- or hypochlorite-disinfected sewage wastewater.

Wastewater disinfection is routinely carried out to prevent the spread of human pathogens present in wastewater effluents. To this aim, chemical and physical treatments are applied to the effluents before their emission in water bodies. In this study, the influence of two widely used disinfectants, peracetic acid (PAA) and sodium hypochlorite (NaClO), on the formation of mutagenic by-products was investigated. Wastewater samples were collected before and after disinfection, in winter and in summer, at a pilot plant installed in a municipal wastewater-treatment plant. Samples were adsorbed using silica C18 cartridges and the concentrates were tested for mutagenicity in the Salmonella typhimurium reversion test with strains TA98 and TA100. Non-concentrated water samples were tested with two plant genotoxicity assays (the Allium cepa root anaphase aberration test and the Tradescantia/micronucleus test). Mutagenicity assays in bacteria and in Tradescantia showed borderline mutagenicity in some of the wastewater samples, independent of the disinfection procedure applied. Negative results were obtained in the A. cepa anaphase aberration test. These results indicate that, in the conditions applied, wastewater disinfection with PAA and NaClO does not lead to the formation of significant amounts of genotoxic by-products.

Disinfectants↗
PubMed2001

By-products formation during drinking water disinfection: a tool to assess disinfection efficiency?

In drinking water treatment, the inactivation of microorganisms increases with increasing disinfectant exposure (product of concentration and contact time, CT). Also, the formation of undesired (toxic) disinfection by-products increases with CT. The present study proposes a new concept that uses this undesired side effect of chemical water disinfection for a fast and reliable test of treatment efficiency. In laboratory systems, bromate formation during ozonation and the formation of trihalomethanes during chlorination were used to calculate the disinfectant exposure, which is a measure for the achieved degree of disinfection.

Animals↗
PubMed2001

Effect of ozonation and UV irradiation with direct filtration on disinfection and disinfection by-product precursors in drinking water treatment.

Pilot plant studies were conducted to evaluate the effect of pre-ozonation and ultraviolet irradiation on disinfection, disinfection by-product precursors and water quality in a direct filtration water treatment system. Disinfection parameters including total coliforms, faecal coliforms and heterotrophic plate count were investigated. Total organic carbon (TOC), trihalomethanes (THMs), total organic halides (TOX), filtered water turbidity and colour were also evaluated. It was found that advanced pre-oxidation processes (ozonation and UV irradiation) significantly increase the level of disinfection of raw water. Removal of total trihalomethanes and total organic halides precursors improved with ozonation and UV irradiation, compared to no oxidation treatment in direct filtration and/or in conventional water treatment. All coliforms (total and faecal) were completely destroyed by ozonation alone, and also with ozonation in conjunction with UV irradiation. However, the heterotrophic plate count was not significantly reduced at an ozone residual concentration of 0.1 mg l(-1). This suggests that disinfection efficiency is strongly influenced by competition reactions of organic and inorganic compounds with ozone. Precursors of total trihalomethanes and total organic halides were reduced by 90% and 98%, respectively, with advanced pre-oxidation processes. Water quality parameters were improved by the pre-ozonation and UV irradiation treatment system.

Disinfectants↗