Hand sanitisers: How well are you protected?
31 July 2020
The rising number of Coronavirus deaths reported in the media is causing us all to take positive steps in protecting ourselves. Sam Awolesi MSc, senior associate member of the Royal Society of Medicine, and Roy Simmons BSc, senior consultant, Environmental Science Group, March, Cambridge, discuss how we can make sure that we are adequately protected.
Government health officials and epidemiologists advocate ‘self-isolation’ and ‘social distancing’. Inevitably though, daily tasks will bring some of us into contact with surfaces that are potentially contaminated with the virus. The advice is to thoroughly wash our hands with soap and water for at least 20 seconds. However, washing with soap and water does not inactivate the virus, but merely removes it from the surface of your skin.
Additional protection from potential contaminated surfaces (eg deliveries) would be to wear plastic gloves, leave the package outside the premises and wipe with a dilute solution of bleach (or spray). Leave for 10 minutes and then wipe dry before opening. While still wearing plastic gloves, carefully dispose of the wipes as bleach solution is corrosive and harmful to the skin. (Note: in order to care for the environment plastic gloves do not have to be disposed after a single use. They can be cleaned with running water, dried and re-used by the same person).
In situations where washing facilities are not available and there is concern that hand contact has been made with a virus-contaminated object, the use of hand sanitiser (with the appropriate alcohol content) would be the best defence. These products are commercially available in various sizes and price.
Use of hand sanitisers
Hand sanitiser is a gel or foam that is marketed as a biocide and is also effective for certain types of virus. It is used as an alternative to hand-washing and is commercially available either as sanitiser that is alcohol-based or sanitiser that is alcohol-free. Approved formulations of these products are given in a publication from the World Heath Organization (WHO).
In order to use hand sanitiser effectively, apply a small amount to the palm of one hand (read the label for the appropriate amount) and then rub both hands together so as to cover all the surfaces of your hands and fingers until your hands are dry.
Alcohol-based sanitiser acts by denaturing protein and dissolving lipid in bacterial cell walls and membranes. It also inactivates enveloped viruses and reduces the infectivity of some non-enveloped viruses.
The majority of hand sanitisers contain a combination of isopropyl alcohol (rubbing alcohol) and ethanol. The percentage of alcohol present in hand sanitiser is key to its efficacy – those with less than 60% alcohol will be less effective at killing micro-organisms, and will just reduce their growth. Many studies have found that sanitisers with an alcohol concentration between 60% to 95% are more effective at killing microorganisms than those with a lower alcohol concentration or non-alcohol-based hand sanitisers.
It is well known that many chemical substances and mixtures when taken orally or applied to the skin can have side effects. This applies to hand sanitiser solutions as well. With repeated use over a long period of time, the active chemicals in these products can be absorbed through the skin. In sufficient quantities, they enter the blood stream and accumulations can occur such as to affect the normal functions of the body’s metabolism in liver and kidneys. The toxic effects of both ethanol and isopropyl alcohol (IPA) are well documented in ECHA registered chemical listings. The toxic effects of IPA are many times higher than that for ethanol alcohol, so the informed choice is obvious in favour of ethanol.
A study reported an extensive survey of 18 retail chains (supermarkets, drug stores, general retailers, specialty shops) and exposed a substandard product at all three stores of a deep-discount chain. The marketing profile of deep-discount chains suggests that poorer segments of the community may be more at risk when it comes to the purchase of inadequate antiseptic gels. Moreover, products containing 40% ethanol may be stockpiled in homes and offices.
However, it was noted that the less common brands of antiseptic gel did not state the alcohol content online. It is important that educational efforts should emphasise that effective sanitisers must be of a sufficient alcohol concentration. Consumers should be alerted to check the alcohol concentration in hand sanitisers because substandard products may be marketed to the public.
The high demand for hand sanitisers at the present time means that the public may purchase these products, and due to the marketing, advertising and statements made on the product labelling, believe them to be substitutes for the conventional hand sanitiser products.
Checking for product safety and effectiveness
It is vital that the manufacturer ensures that products on the market are effective and do not pose an unacceptable risk to people or the environment. The HSE has highlighted the fact that biocidal hand sanitisers that are made available in the UK to help protect people during the Coronavirus outbreak must be safe and effective.
How can consumers know what chemicals are in a certain product?
A starting point is to request a Safety Data Sheet (SDS) which the supplier or manufacturer is legally obliged to issue to the end users. This is formalised today by the internationally accepted Global Harmonised System (GHS). The document procedure and the details contained therein are directed by the United Nations. The information given in various sections of the SDS affords the declaration of a product’s hazardous classified contents along with other notations on any toxic properties and exposure limits.
For hand sanitisers that comply with WHO formulations, Section 2 of the SDS should declare the product classification as highly flammable liquid and causing serious eye irritation. If the SDS is GHS compliant, Section 3 should list the main hazardous components and should include the name and concentration of the alcohol used in the product. If the level of alcohol declared is less than 60%, then the biocidal and virucidal level of protection will not be as effective as when the alcohol is more than 70%.
Another way to check compliancy is to read the product label, which should include the type and amount of alcohol used in the hand sanitiser.