Jessica Wilson, head of research at Consumer New Zealand, said some online recipes suggest using essential oils instead of alcohol – rendering it ineffective in the fight against coronavirus, let alone any other virus.
She said hand sanitisers must contain a sufficient alcohol concentration – at least 60%, per the Ministry of Health advice.
“Those guidelines aren't aimed at the average DIY enthusiast and require materials you're unlikely to have lying around, such as an alcoholometer and large quantities of highly flammable ingredients," she said.
"Commercial hand sanitisers also contain emollients to keep your skin soft and reduce any damage. Important, because dry and damaged skin can increase the risk of bugs entering through cuts in the skin.
"While many DIY recipes suggest adding aloe vera for its moisturising properties, if you don't get the ratio right you also run the risk of diluting the alcohol concentration, rendering it ineffective.”
Wilson said Consumer New Zealand had received complaints about hand sanitiser products being advertised online for hundreds of dollars a litre.
"The situation has resulted in a multitude of homemade recipes for hand sanitiser appearing online, with claims they're just as effective as commercial products.
"We are aware that people have been looking online where you can find a raft on suggestions on how to make hand sanitiser. However, there are significant problems if you get it wrong,'' Wilson warned.
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