Stability of antimicrobial activity of peracetic acid solutions used in the final disinfection process

Abstract

The instruments and materials used in health establishments are frequently exposed to microorganism contamination, and chemical products are used before sterilization to reduce occupational infection. We evaluated the antimicrobial effectiveness, physical stability, and corrosiveness of two commercial formulations of peracetic acid on experimentally contaminated specimens. Stainless steel specimens were contaminated with Staphylococcus aureus, Escherichia coli, Candida albicans, blood, and saliva and then immersed in a ready peracetic acid solution: 2% Sekusept Aktiv (SA) or 0.25% Proxitane Alpha (PA), for different times. Then, washes of these instruments were plated in culture medium and colony-forming units counted. This procedure was repeated six times per day over 24 non-consecutive days. The corrosion capacity was assessed with the mass loss test, and the concentration of peracetic acid and pH of the solutions were measured with indicator tapes. Both SA and PA significantly eliminated microorganisms; however, the SA solution was stable for only 4 days, whereas PA remained stable throughout the experiment. The concentration of peracetic acid in the SA solutions decreased over time until the chemical was undetectable, although the pH remained at 5. The PA solution had a concentration of 500-400 mg/L and a pH of 2-3. Neither formulation induced corrosion and both reduced the number of microorganisms (p = 0.0001). However, the differences observed in the performance of each product highlight the necessity of establishing a protocol for optimizing the use of each one.

Effect of peracetic acid on biofilms formed by Staphylococcus aureus and Listeria monocytogenes isolated from dairy plants

“…In contrast, the 5 bacterial strains tested in the present study were damaged by PAA after 15 s, with almost 100% of cells damaged after 30 s (L. monocytogenes) or 60 s (S. aureus). After contaminating stainless steel with S. aureus, Escherichia coli, and Candida albicans, Costa et al (2015) immersed the specimens in 2% and 0.25% PAA for 30 min, and both concentrations significantly eliminated the microorganisms, a result that corroborates the findings of the present study. Moreover, S. aureus and L. monocytogenes are grampositive bacteria with a permeable cell wall (Schäffer and Messner, 2005), which is not considered a barrier to the entrance of antibacterial compounds through the cytoplasmic membrane (Júnior et al, 2014).…”

Effect of 0.2% peracetic acid disinfection on the horizontal dimension of implant framework indexed with two autopolymerized acrylic resins

“…The use of peracetic acid on microbiological disinfection was reported previously [28] and successfully managed the disinfection of the samples after 5 min and 10 min of immersion [17, 28]. In our study, the disinfection protocol with 0.2% peracetic acid consisted of 10 min immersion, according to the manufacturer’s recommendation for high-level disinfection.…”

“…Superficial changes of the acrylic resins have been evaluated by Chassot et al [17] who demonstrated that peracetic acid did not affect superficial roughness and color of the resins. However, limited literature is available about the effect of the peracetic acid solution on metallic surfaces [18, 28] and further studies are needed. Additionally, some authors have reported adverse effects of exposure to peracetic acid in higher concentrations (2%) by hospital cleaning staff, such as work-shift eye and upper and lower airway symptoms [29], but no report is available for low concentration as 0.2% peracetic acid solution in dental use.…”

Preliminary Study on Scanning Electron Microscopy as an Additional Mean to Assess the Effectiveness of Sterilization of Endoscopes Used in Digestive Tract Examination

“…Equally, it ensures an excellent disinfection in a short time span. It is however necessary the setting up of an optimal protocol for using the final disinfection solutions [24][25][26].…”