Methanol and 1-propanol could get into hand gels by unintentional or deliberate adulteration.
Katrina Megget from Chemistry World - a publication from Royal Society of Chemistry speaks to Dr Hamid Merchant at the Univesity of Huddersfield for potentail sources of this contamination, safety, and impact during pandemic.
Since June, 160 alcohol-based hand sanitisers containing toxic contaminants have been identified by the US Food and Drug Administration (FDA). Testing has revealed methanol contamination ranging from 1% to 80%, while other products are tainted with 1-propanol. This poses significant health risks given the increase in use of such products driven by the Covid-19 pandemic
Several people have died after ingesting the contaminated sanitisers and there have been reports of other adverse events from their use, including blindness, cardiac arrest, effects on the central nervous system and hospitalisations.
Handsanitisers in CoViD-19