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It’s important to understand the difference between sanitising and disinfecting.

Sanitising refers to cleaning one’s hands in order to reduce the number of potential pathogens that could be transmitted to others.

Disinfecting refers to killing pathogens on surfaces, which may require chemicals harmful to humans, animals and the environment.

Many manufacturers have confused the two concepts and produced hand sanitisers containing disinfecting chemicals that can dehydrate or irritate one’s skin, or cause even more serious effects. Health preservation depends on knowing the difference between sanitisation and disinfection.

Why are chemical disinfectants harmful to use on hands?

There are many chemicals found in hand sanitisers that are potentially harmful to humans and environment.

Here are some potential toxic effects of harmful chemicals:

  • Skin and eye irritation
  • Sensitization of the skin
  • Acute and chronic toxicity and generalised inflammation
  • Developmental and reproductive toxicity
  • Cell changes and tumour formation
  • Toxicity to the nervous system
  • Impairment of the immune system
  • Irritation of the respiratory system
  • Impairment of detoxification systems.

Which chemical ingredients are potentially harmful to humans and the environment?

What is safer and effective to use for sanitising?

Soap

Soap and water work best because the viral envelope is a 3D-lipid membrane which interacts with soap and is washed away very effectively by water. Soaps are surfactants meaning they have hydrophilic heads and hydrophobic tails. The hydrophobic tail sticks to the virus and the virus is lifted off a surface or tissue and washed away! Soap remains the best remedy, and is scientifically validated.

  • Liquid Castile soap is a non-toxic, vegetable based soap that is an all-purpose alternative to sanitization and a general body and home/environmental cleaner. It was traditionally made from an olive oil base.
  • Glycerine and other natural soap bars.

Stable Hypochlorous acid

HOCL is one of the most effective known biocides (100 x more deadly against microbes than Hypochlorite). This weak acid with the chemical name HClO or HOCL is the same chemical produced by the human immune system to kill invasive organisms and fight infection. As it is a biocide it is safe for humans and animals, and is hydrating as well. Chemical free, all natural, non-toxic – as long as it is stable and not mixed with other compounds.

All hypochlorous acid products without fragrance, oils, additives are good for use. As hypochlorous acid breaks down to chlorine, it may still irritate mucous membranes and skin, although claims are made that it is safe to use even in the ocular space and in/on wounds as an antiseptic.

There are some other products available commercially, which are being investigated for efficacy and safety, and these will be added to this list as they come to light.

Isopropyl alcohol and Ethanol

  • Isopropyl alcohol at 60-70% is recommended by WHO all over the world as being virucidal against SARS-Cov-2.
  • A paper published in 2017 (Kampf G) demonstrated that SARS coronavirus was susceptible to ethanol at 70% with a dwell time of 30 seconds, and this is probably what the WHO based its recommendations on. However surrogate virus testing has been shown to not be reliable, so one cannot assume that SARS-Cov-2 will be susceptible. (Geller C)
  • Actually 94.9% is required to kill the SARS-Cov-2 with a dwell time of 30 seconds on hard surfaces, but this would be too damaging for use on the skin. (US EPA) For increased efficacy, it needs to be combined with other disinfectants, which are contraindicated for topical use.
  • Although 70% ethanol has been tested against other coronaviruses, it cannot be assumed that it will necessarily be effective against SARS-Cov-2.
  • Thus, the reality is that most alcohol-based hand sanitisers may, in time, be proven to be ineffective against SARS-Cov-2.

What about essential oils?

Essential oils can have potent effects, but must be used with caution. Although many EOs have been studied with respect to their effects on bacteria and fungi, most scientific research on viruses has been done on Herpes viruses. Traditional usage in viral infections, while considerable, is therefore mostly empirical.

Essential oils do not mix with water, as they are lipophilic. At best they can remain in brief temporary suspension. They do however dissolve in alcohol and vegetable oil/lipidic bases.

Some individuals can develop sensitivity or skin irritation to ‘safe’ oils. Many essential oils are dermal irritants and/or sensitizers, even those considered ‘safe’.

If EOs are included in a hand sanitiser, the volume should not exceed 1% in total.

Tea tree, eucalyptus, lavender, rosemary, sweet orange, lemon are relatively safe, antiseptic, anti-microbial and possibly anti-viral.

Lemongrass, citronella, bergamot, thyme, oregano, cinnamon bark and leaf, lemon balm and clove bud should be avoided in topical application due to dermocaustic and dermal sensitizer chemicals constituents (phenols and aldehydes) in their make-up, which compounds are responsible for adverse reactions on the skin (including phototoxicity).

Potential harm to environment

Avoid:

  • Chemicals on the list above.
  • Aerosol bottles [choose pump action bottles instead]
  • Non-recyclable plastic containers.
  • Wet wipes (which do not decompose)

Bottom line

Wash your hands with soap, whenever possible, after exposure to risk, and moisturise hands with skin-supporting, safe hand lotions if using lots of hand sanitizer or excessive hand washing.

When out shopping, avoid the commercial hand sanitisers. Rather carry your own safer sanitiser, or a bottle of liquid soap to apply to hands, followed by a squirt of water from a little water container. Dry with a tissue.

Issued by SASIM in collaboration with Carin Smit (Toxicologist)
July 2020