Hypochlorous acid water, claimed to be effective against viruses on surfaces
The rising spread of COVID-19 has increased the demand for products advertised as effective for sanitization or disinfection, various types of which are offered in stores. Among them, there are many products sold as hypochlorous acid water which are claimed to be as effective against viruses.
In June 2020, the Ministry of Health, Labour and Welfare, the Ministry of Economy, Trade and Industry, and the Consumer Affairs Agency jointly released a document entitled "Disinfection and Sanitization against COVID-19". The document lists several liquids effective against viruses on surfaces: hot water, chlorine bleach (sodium hypochlorite), detergent (surfactant), hypochlorous acid water, and alcohol in a certain concentration. The properties and handling of hypochlorous acid water basically depend on the manufacturing process and ingredients. The effective chlorine concentration (residual chlorine concentration) and the acidity are regarded as markers of the efficacy of hypochlorous acid water. On the other hand, it has been reported that the concentration of hypochlorous acid, pH, manufacturing process and ingredients are not indicated on many of the products sold as hypochlorous acid water.
Moreover, PIO-NET has received 498 inquiries about hypochlorous acid water out of those related to COVID-19. Some of the cases include harmful incidents (e.g. "I had tingling of hands.").
Therefore, NCAC decided to examine 15 brands of hypochlorous acid water on the market concerning effective chlorine concentration, pH and labeling to share relevant information with consumers.
Effective chlorine concentration
- Of the 15 tested products, 14 products indicate the effective chlorine concentration on the package, in the instruction manual or on the website. Concerning 8 out of the 14 products, the effective chlorine concentration was sometimes 90% or less of the concentration indicated (the concentration varied depending on the purchase period).
- The pH of the tested products ranges from mildly acidic to neutral. Of the 15 tested products, 13 products indicate pH values on the package, in the instruction manual or on the website. Two out of the 13 products indicate pH values different from the actual values.
Examination of labeling and advertising
- Five out of 15 products don't indicate the effective chlorine concentration on the package, in the instruction manual, etc.
- Nine products don't indicate the instruction to wipe dirt off before use on the package, in the instruction manual or on the website.
- Five products indicate on the package, in the instruction manual or on the website the efficacy of cleaning hands and mouth, which is very close to the efficacy of cosmetics, and may mislead consumers.
- Five products don't indicate the use-by date on the package, in the instruction manual, etc.
Advice for consumers
- Remember that the effective chlorine concentration of hypochlorous acid water may change and differ substantially from the concentration indicated when the product is purchased.
- Before buying or using hypochlorous acid water, carefully read the effective chlorine concentration, pH, use-by date, usage, etc.
- There are several options for sanitizing and disinfecting surfaces which may be contaminated with COVID-19: hypochlorous acid water, alcohol in a certain concentration, surfactant, etc. Choose the suitable one for your purpose.
Request to businesses
- Indicate the effective chlorine concentration, pH, use-by date and usage on the package and in the instruction manual. Please ensure that the effective chlorine concentration and the pH are maintained as indicated within the consumption period.
- Efficacy and other properties should not be misled by product labels and other statements. Improve them as appropriate.