How Aqueous Ozone Differs from Harsh Chemical Antimicrobials


Comparing the Safety of Chemical Antimicrobials and Aqueous Ozone

Antimicrobials are synthetic chemicals that kill small germs such as bacteria, viruses, and/or fungi. Usually, the antimicrobial works on small organisms and on humans in the same way. That means that if you’re killing germs with an antimicrobial chemical, you’re risking damage to yourself, too.

Ozone is distinct from other antimicrobial chemicals in two main ways.  First, although it can be made synthetically through ultraviolet (UV) radiation or electricity, it is also a naturally occurring molecule.   Second, aqueous ozone is safe for humans to use. It has a Generally Regarded as Safe (GRAS) designation from the US Food and Drug Administration (FDA) and disappears within minutes, leaving no risk of exposure to dangerous chemicals.  

Let’s look at what you can expect from aqueous ozone compared to any other chemical antimicrobial you may be using for your sanitizing needs.

1. Check Your Antimicrobial’s Ingredients List

Aside from ozone, typical antimicrobial chemicals consist of alcohol, bleach, quaternary ammonium compounds, phosphates, peroxides, peracetic acid, or formaldehyde. Check the ingredients list on your bottle to see which chemicals you may be using. You may find a mixture of other chemicals in addition to the active ingredient. Aqueous ozone’s only input is potable tap water. 

Bleach is the most common household antimicrobial chemical. It comes in a variety of storage and release forms, but the active substance is an equilibrium of hypochlorous acid (HOCl) and its dissociated form, hypochlorite ion (OCI). 

2. Stability

Aqueous ozone produced from the Enozo bottle has a short half-life, meaning that within 10 minutes, ozone is no longer detectable on the surface where it was sprayed. This makes ozone the safest and most environmentally friendly antimicrobial agent available. Ozone goes in, kills microbes, and leaves. It won’t stick around to damage a surface or irritate skin.

Chemicals such as alcohol and concentrated bleach solutions last in the environment for months or years. Peroxide degrades at a rate less than 2% per year when stored in a dark container. Peracetic acid in its 40% storage form loses 1%-2% active ingredient per month. Quaternary ammonium compounds are notoriously long-lived and can remain in the environment indefinitely; some have been discontinued for lack of biodegradation.

3. Irritation and Sensitivities

Remember that chemicals that harm microbes might harm you. Bleach can cause respiratory or eye damage and can burn skin. Peroxides can irritate skin and mucous membranes. Alcohol can damage surfaces and dry out skin. Quaternary ammonium compounds can contribute to the development of asthma.

The amount of damage depends on the concentration of chemical you’re exposed to and, for how long, and how often.

Not only does ozone have a Generally Regarded as Safe (GRAS) designation from the U.S. FDA, it is also recognized as safe and highly effective by the National Sanitation Foundation. It contains no additives, fragrances, or dyes that could contribute to skin, eye, or respiratory irritation or sensitivities. Further, the FDA formally approved the use of ozone as an Antimicrobial Agent for the Treatment, Storage and Processing of Foods in Gas and Aqueous Phases. It can be used in direct contact with meats and poultry, food processing equipment and other non-food contact surfaces. Even direct contact of aqueous ozone on skin does not cause irritation, injury, or harm.

4. Concentrations

Bleach is stored at concentrations of about 5% and is diluted 1:10 for a final concentration of 0.5%.  Aqueous ozone from the Enozo bottle is at a concentration of about 1 part per million (ppm), which corresponds to 0.0001%.  Even diluted bleach has 5,000 times the chemical concentration of aqueous ozone from an Enozo bottle! 

Alcohol works only at specific concentrations; it must be above 50% but below 95%. Pure alcohol does not have antimicrobial properties; it needs some water in the mix to do its work. Moreover, since alcohol evaporates more readily than water, your 60% alcohol-based hand sanitizer might dip below the 50% efficacy mark without your awareness.  

Formaldehyde is stored at 37% and used at concentrations of 2%-8%.  Peroxides are used at concentrations between 0.5% and 7.5%.  Peracetic acid has efficacy at 0.1% to 3.5%.

5. Contact time

It is important to read the labels of any product to determine the appropriate contact time, or dwell time. This is the time you need to wait after you apply your antimicrobial to get full efficacy before you rinse or wipe. Different organisms are killed at different contact times. Household bleach has a contact time of up to 10 minutes for certain microorganisms. The contact time can be longer at lower concentrations. Hydrogen peroxide and peracetic acid can take up to 30 minutes. If you simply spray and wipe with your standard antimicrobial, you’re not getting the results that the product claims.

The Enozo spray bottle kills in 30 seconds and does not leave behind any residues that require wiping. When ozone encounters soils, pathogens and microbes that cause odors or illness, it reacts instantaneously. By nature, ozone works faster than conventional chemicals because of its high redox potential.  This means that it reacts with many different types of microbes, kills them quickly, and reverts back to water in minutes.

6. Personal Protective Equipment (PPE)

Look at the Material Safety Data Sheet (MSDS) provided with your antimicrobial chemicals to see what kind of personal protective equipment is recommended. Bleach requires the use of rubber gloves, eye protection, long sleeves and pants, and closed-toed shoes. Formaldehyde is regulated by OSHA standards and requires eye protection and chemical-resistant gloves and clothing.  

The Enozo bottle produces levels of aqueous ozone well beneath the OSHA limits for even long-term exposure. It can even be applied directly to exposed skin without the use of PPE.

7. Chemical Reactivity

If you’re using several different antimicrobial chemicals for specific tasks and surfaces, it is very important to keep them separated. If they come together, they can react with each other to produce even more toxic substances. 

Bleach is especially susceptible to dangerous reactions with other chemicals. Bleach diluted in hot water can produce the carcinogen trihalomethane.  When it encounters formaldehyde, it can produce the carcinogen bis(chloromethyl) ether. Bleach and ammonia combine to create the toxic gas chloramine and bleach in the presence of peroxide could explode. 

Proper storage of antimicrobial chemicals is a must. Enozo’s bottle creates aqueous ozone on-demand, eliminating risk and freeing up storage space.

Enozo’s Aqueous Ozone

Enozo’s Aqueous Ozone provides myriad benefits as a chemical-free alternative to stable harsh antimicrobial chemicals. It is a simple, safe solution to industrial and home sanitization needs by generating a small concentration of a fast-acting, short-lived antimicrobial that leaves no residue. It’s safe for humans, pets, and any surface on which you would use water. Replacing your stable harsh antimicrobial chemicals with the on-demand Enozo bottle keeps you and your environment safe and protected.

Picture of Author | Xu Simon, PhD, MBA

Author | Xu Simon, PhD, MBA

Enozo Chief Technology Officer