Bactericidal and Fungicidal Efficacy of Chlorine Dioxide in Various Workspaces
Open Access
- 1 January 2022
- journal article
- research article
- Published by Scientific Research Publishing, Inc. in Occupational Diseases and Environmental Medicine
- Vol. 10 (02), 49-59
- https://doi.org/10.4236/odem.2022.102004
Abstract
Previously, we demonstrated the virucidal efficacy of low concentration chlorine dioxide (ClO2) gas in room settings. The purpose of these studies was to evaluate novel ClO2 formats as potential biocidal interventions for real world congregate settings and air systems. Three types of studies were conducted to determine the efficacy of ClO2 in reducing bacteria and mold in various workspaces: hard and soft surfaces (gymnasium & equipment), aerosol (in-room), and within a laboratory environment. The study demonstrated that ClO2 was highly effective against both bacteria and mold with reduction ranging from 85.0% - > 99.4% for bacteria and >99.4% for yeast and mold. Treatments on hard and soft surfaces (gymnasiums and sports equipment), reduced bacteria by an average of 90% - 95%. The following treatments were applied overnight: 1) hard surface spraying with dilute ClO2 solutions, 2) carpet and tumbling treatments with powdered ClO2 releasing impregnates, and 3) HVAC treatment and overall room deodorization with low dose ClO2 gas from controlled releasing sachets. The in-room study treating air with a ClO2 filtration media also indicated significant air and surface room efficacy, with an average of 94% reduction in bacteria after 24-hour, and 99.4% reduction in mold after 24-hours. In a related air study, a biological combination of Raoultella terrigena and Staphylococcus aureus was injected as a bio-aerosol into a 4-inch diameter pipe with air flowing at approximately 1200 ft/min. Dry ClO2 gas was introduced into the air flow to achieve an effective concentration of 5 or 10 ppmv. Air samples were collected at sampling ports downstream from the fan at 10, 22, 55 and 100 ft along the pipe and used to evaluate changes in airborne bacteria and mold. Testing was conducted in a laboratory setting at ambient conditions. The data showed ClO2 gas reduced viable organisms at both gas concentrations, and indicated that reductions were higher for 10 ppmv concentration, and longer pipe runs. In a final study, laboratory application of gaseous chlorine dioxide was tested. Low gas release filter testing demonstrated significant surface reductions of airborne bacteria with an overall average 99.4% reduction in the 24-hour testing period. Higher gas treatments of a class II biological cabinet reduced bacillus spores on steel coupons throughout cabinet by 6 log. ClO2 was effective as a bactericidal and fungicidal treatment providing significant reduction in both surface and air. Novel product delivery forms may be useful for rapidly disinfecting air and solid surfaces in complex congregate settings.Keywords
This publication has 8 references indexed in Scilit:
- Virucidal Activity of Chlorine Dioxide Gas for Reduction of Coronavirus on Surfaces and PPEOccupational Diseases and Environmental Medicine, 2021
- Bacterial community analysis of floor dust and HEPA filters in air purifiers used in office rooms in ILAS, BeijingScientific Reports, 2020
- Bioaerosols and Transmission, a Diverse and Growing Community of PracticeFrontiers in Public Health, 2019
- Efficacy and Safety Evaluation of a Chlorine Dioxide SolutionInternational Journal of Environmental Research and Public Health, 2017
- Six-month low level chlorine dioxide gas inhalation toxicity study with two-week recovery period in ratsJournal of Occupational Medicine and Toxicology, 2012
- Bacterial contamination of computer keyboards and mice, elevator buttons and shopping cartsAfrican Journal of Microbiology Research, 2011
- Evaluation of the Antiviral Activity of Chlorine Dioxide and Sodium Hypochlorite against Feline Calicivirus, Human Influenza Virus, Measles Virus, Canine Distemper Virus, Human Herpesvirus, Human Adenovirus, Canine Adenovirus and Canine ParvovirusBiocontrol Science, 2010
- Effect of Chlorine Dioxide Gas on Fungi and Mycotoxins Associated with Sick Building SyndromeApplied and Environmental Microbiology, 2005