Effect of peracetic acid and aldehyde disinfectants on biofilm

The effects of two aldehyde (Cidex, Endosporine) and four peracetic acid (PAA) (Nu Cidex, Anioxyde 1000, Hydraseptic, Peralkan) disinfectants on an Escherichia coli biofilm model were studied. The biofilm was prepared in glass tubes, and evaluated indirectly using a colourimetric method. The ability of the disinfectants to fix or remove the biofilm from tubes was determined by their detergent activity (DA). The two aldehyde derivatives and two of the PAA (Nu Cidex, Anioxyde 1000) agents fixed the biofilm. However, the effects of Hydraseptic and Peralkan were equivalent to the control (sterile water). Regardless of their disinfectant activity, PAA agents display different DAs that could be used to select the weakest biofilm-fixing agents. Users should be concerned about the efficiency of the cleaning stage of medical devices, and when choosing a PAA product, non-fixing ability should be considered in addition to antimicrobial activity.     

过氧乙酸类消毒剂对生物膜消毒清除效果

目的研究3种过氧乙酸消毒剂对铜绿假单胞菌人工生物膜的去除率,并对使用过的内镜进行临床消毒试验,评估3种消毒剂对生物膜的去除效果。方法参照T/WSJD 002-2019人工制备生物膜;按照WS507-2016和GB 15982-2012进行内镜的临床消毒试验,并采样检测内镜消毒的质量,综合评价消毒剂去除生物膜的效果。结果平整表面培养法和管腔内表面培养法制备的人工生物膜细菌计数达1×107~1×108CFU/样本;消毒作用1 min,3种消毒剂对两种生物膜的去除率均为100.00%;243条内镜临床试验的菌落总数A0<20 CFU/件,B090%,达到合格标准;表明消毒剂可达到高水平消毒,对生物膜有清洁去除效果。     

Surface fixation of dried blood by glutaraldehyde and peracetic acid

The difficulties of successful prion inactivation by chemical agents has led to changes in recommendations regarding the reprocessing of instruments including flexible endoscopes. One of the changes is the preference for peracetic acid instead of glutaraldehyde in order to avoid fixation of organic material, but the surface fixation by various active agents has not been fully investigated. We used a standardized amount of dried blood soil on metal carriers (on average 22 mg). One part of the carriers was exposed to different disinfectants (four based on peracetic acid, three based on glutaraldehyde, two based on quaternary ammonium compounds (QAC), one based on QAC and amines, one based on phenols and one cleaning agent) and air dried. The difference compared with the non-exposed soiled carrier was taken as the measure of blood removal by exposure to the disinfectants. In addition the other part of the carriers was exposed to a cleaning agent and air dried. The cleaning agent itself was capable of removing more than 99% of the dried blood and served as a control for non-fixation. The rate of fixation of dried blood was calculated as the ratio of the weight of residual soil on 'soiled, disinfected and cleaned' carriers and on 'soiled and disinfected' carriers. All experiments were repeated eight times. Blood removal varied between 90.3% +/- 1.5% (phenol-based disinfectant) and < 10% (glutaraldehyde-based preparations). Fixation of the remainder was between 76.9 +/- 8.4% and 102.5 +/- 1.1% with glutaraldehyde and between 19.2% +/- 3.3% and 78.1% +/- 2.4% with peracetic acid. No other preparations showed a potential for blood fixation (< 1.3%). Our findings underline the potential for blood fixation, not only by glutaraldehyde, but also by peracetic acid, and support the evidence that effective cleaning should precede the chemical disinfection.     

Evaluation of genotoxicity of sodium hypochlorite, chlorine dioxide and peracetic acid using plant tests

The aim of this research was to evaluate the potential genotoxic effects of three drinking water disinfectants by means of in vivo short-term mutagenicity tests using plants. The study was carried out in laboratory using distilled water disinfected with sodium hypochlorite (NaClO), chlorine dioxide (ClO2) and peracetic acid (PAA) at different concentrations both in neutral and acid conditions. Untreated distilled water was used as a negative control. Micronuclei test in Tradescantia pollen cells and chromosomal aberration test in root cells of Allium cepa were the bioassays performed by exposing directly plant bioindicators to treated and untreated distilled water. The Tradescantia/micronuclei test gave positive results in most of the ClO2-treated water samples but only at acid pH. The Allium cepa test showed genotoxicity in NaClO-treated samples at acid pH and in a ClO2-treated sample at pH 7. PAA-treated samples were always nongenotoxic. Since the concentrations tested of free disinfectants are usually present in drinking water for biocidal purposes, genotoxicity of these compounds could be a public health problem.     

Comparative biocidal activity of peracetic acid, benzalkonium chloride and ortho-phthalaldehyde on 77 bacterial strains

Despite numerous reports on biocide activities, it is often difficult to have a reliable and relevant overview of bacterial resistance to disinfectants because each work challenges a limited number of strains and tested methods are often different. The aim of this study was to evaluate the bactericidal activity of three different disinfectants commonly used in industrial or medical environments (peracetic acid, benzalkonium chloride and ortho-phthalaldehyde) against 77 bacterial strains from different origins using one standard test method (NF EN 1040). Results highlight the existence of high interspecific variability of resistance to disinfectants and, contrary to widespread belief, Gram-positive strains generally appeared more resistant than Gram-negative strains. Resistance was also variable among strains of the same species such as Bacillus subtilis to peracetic acid, Pseudomonas aeruginosa to benzalkonium chloride and Staphylococcus aureus to ortho-phthalaldehyde.     

软式内镜一元过氧乙酸消毒液消毒效果

目的评价一元低腐蚀性过氧乙酸消毒液对通过建立铜绿假单胞菌生物膜模型的内镜钳子管道的消毒和生物膜去除效果,并观察验证过氧乙酸消毒液消毒的有效性和时效性。方法生物膜去除效果检测选取奥林帕斯内镜售后服务机构集中回收的临床已使用的内镜钳子管10条搭建生物膜模型后采用过氧乙酸浸泡后抽样。临床观察消毒液有效性和时效性,选取2019年1-12月300条胃镜和300条肠镜作为研究对象,采用过氧乙酸消毒液消毒,统计内镜消毒效果;比较每条内镜连续5 d经步骤a、b来采集样本以检测管道表面附着情况。比较连续使用14 d,浸泡212条内镜后消毒效果。结果内镜钳子管道经过刷洗+过氧乙酸杀灭5 min和15 min,细菌培养无菌生长,生物膜有效去除。胃镜消毒后菌落数平均为(9.362±2.621)CFU低于消毒前菌落数(P<0.001),胃镜消毒合格率为100.00%(300/300)。肠镜消毒后菌落数为0 CFU低于消毒前(P<0.001);肠镜消毒合格率为100.00%。连续使用过程中采集天数对菌落数目无明显影响,且采集天数、采集步骤的交互作用对菌落数目无明显影响。连续使用14 d后浓度仍>1 000 mg/L,为有效浓度,消毒后内镜抽样合格率为100.00%。结论过氧乙酸消毒液在软式内镜消毒中具有较好效果,能有效去除生物膜,具有较高安全性。     

Effect of different stabilized preparations of peracetic acid on biofilm

The effect of three stabilized peracetic acid (PAA) preparations (Bioxal M), with or without surfactants, on an Escherichia coli biofilm model was studied. The biofilm was prepared in glass tubes, and was evaluated indirectly using spectrophotometry. The ability of the products to fix or remove the biofilm was determined by their detergent activity (DA). None of the preparations tested fixed the biofilm. The effect of Bioxal M-1 on the biofilm was equivalent to the control (sterile water). Bioxal M-2 and Bioxal M-3 displayed slightly positive DAs. Non-ionic surfactant improved the DA of the products. Regardless of disinfectant activity, PAA agents display different DAs depending on their formulation. This criterion could be used to select the weakest biofilm-fixing agents. Users should therefore be concerned about the efficiency of the cleaning stage of medical devices. When choosing PAA products, non-fixing ability should be considered in addition to antimicrobial activity.     

“非典”期间过氧乙酸消毒剂卫生监督情况

过氧乙酸具有很强的抗菌作用 ,杀菌能力较强 ,易分解 ,为无色、无臭、无公害的消毒剂。“非典”防治期间用过氧乙酸进行环境消毒。为了保证过氧乙酸的卫生质量、使用安全和消毒效果 ,对江苏省生产、销售和使用过氧乙酸的单位进行了一次专项监督检查 ,对检查情况进行了分析 ,提出了规范健康相关产品市场监督整治意见 ,并为以后的市场整治和卫生监督管理提供了依据。1　对象与内容1 .1　检查对象　 2 0 0 3年 5月 1 2日～ 30 0 3年 5月2 1日对江苏省范围内 35 0家生产、销售和使用过氧乙酸消毒剂的单位进行了一次卫生监督检查。1 .2　检查内容…     

过氧乙酸上消化道灼伤的护理体会

过氧乙酸在“非典”期间广泛用于家庭消毒，由于得到容易，存放随意，容器多为无明显标识的矿泉水瓶，口服意外事故较为频发。笔者现将我院2003年5月至2004年5月收治的13例口服过氧乙酸患者的护理体会总结如下。     

过氧乙酸复方消毒剂消毒效果的研究

目的研究过氧乙酸复方消毒剂消毒效果。方法 把消毒剂配制成不同浓度进行悬液定量杀菌试验及金属腐蚀试验。结果 以500mg.L^-1过氧乙酸或300mg.L^-1有效氯作用15min,对枯草杆菌黑色变种芽胞的杀灭率分别为99.94%、97.91%;含两的复方对其杀灭率达100%,该复方杀菌作用受有机物的影响较单一成分小;对金属的腐蚀性小于过氧乙酸,而大于二氯二甲基海因,结论,组成复方消毒剂后,明显提高了杀菌效果,而且减轻了对金属的腐蚀性。     

过氧乙酸消毒剂对人体健康影响的调查

目的 了解非典型肺炎流行时期消毒剂对不同人群的影响情况。方法 对182名非职业人群和65名护士进行问卷调查。结果 50％以上的普通人群在喷洒浓度为0．2％过氧乙酸消毒剂、频率为2～3次／d的工作环境中，每天暴露8～12h表现出诸如皮肤发痒、眼睛不适、呼吸困难等不良症状；70％以上的职业人群(医院护士)在喷洒浓度为0．5％过氧乙酸消毒剂、频率为3～5次／d的工作环境中、每天暴露8h，表现出皮肤有灼烧感、眼睛流泪、疼痛、咳嗽等症状。结论 长时间在喷洒浓度为0．2％～0．5％的过氧乙酸消毒剂环境中人体会产生不良健康效应。     

Mutagenicity and disinfection by-products in surface drinking water disinfected with peracetic acid

The aims of this research were to study the influence of peracetic acid (PAA) on the formation of mutagens in surface waters used for human consumption and to assess its potential application for the disinfection of drinking water. The results obtained using PAA were compared to those found with sodium hypochlorite (NaClO) and chlorine dioxide (ClO2). The Ames test, root anaphase aberration assay, and root/micronuclei assay in Allium cepa and Tradescantia/micronuclei test were used to evaluate the mutagenicity of disinfected samples. Microbiological tests were also performed, and disinfection by-products (DBPs) were identified using gas chromatography/mass spectrometry (GC/MS). A slight bacterial mutagenicity was found in raw lake and river water, and similar activity was detected in disinfected samples. A plant test revealed genotoxicity in raw river water, and microbiological analysis showed that PAA has bactericidal activity but lower than that of the other disinfectants. The DBPs produced by PAA were mainly carboxylic acids, which are not recognized as mutagenic, whereas the waters treated with the other disinfectants showed the presence of mutagenic/carcinogenic halogenated DBPs. However, additional experiments should be performed with higher concentrations of PAA and using water with higher organic carbon content to better evaluate this disinfectant.     

Comparative study on HAV and Poliovirus 2 inactivation cinetics with peracetic acid

Hepatitis A virus and Poliovirus 2 inactivation tests were carried out using three peracetic acid concentrations (160, 320 and 640 mg/l) at different pH condition and at +20 degrees C temperature. HAV HM-175 strain was grown in FRhK4 cells and titrated in PFU (plaque technique) and the Poliovirus 2 strain was grown in monkey kidney cells RC-37 and titred in TCID50. The viral titration reduction was determined in the space of an hour with the disinfectant contact at 10-15 minutes intervals. The results obtained with the hepatitis A virus have shown a good linear trend between viral titration and contact time at the highest concentrations without any particular pH influence. The complete viral activity absence was achieved after 30-60 minutes of contact at 640 mg/l concentration. As regards Poliovirus 2 a good linear trend was highlighted between titrations and times at all the concentrations in shorter times at pH acid. The complete viral activity absence was obtained with 640 mg/l concentration after 30 minutes at pH acid. The HAV seems to own a higher resistance than Poliovirus 2 and Poliovirus 1 too.