ECJ EUROPEAN Cleaning Journal

Using a hand sanitiser is better for the environment than washing the hands with soap and water, according to new research.

Scientists from Trinity College Dublin studied the environmental impact of four hand hygiene practices: using an ethanol-based sanitising gel, an isopropanol-based gel, liquid soap with water, and bars of soap with water.

The effects of all four methods were rated under 16 categories including climate impact, freshwater ecotoxicity, ozone layer depletion and water use. The results showed that isopropanol-based sanitising gel had the lowest impact in 14 out of the 16 categories. And in the climate category, the impact of isopropanol-based was four times lower than that of hand-washing with liquid soap.

According to the study authors: "Isopropanol performed better across nearly all measurements compared with ethanol except for fossil fuel use. When the results were normalised, fossil fuel use was found to be the least important of the 16 impact categories measured in this life cycle assessment."

Research author Dr Brett Duane said hand hygiene had been a major help in slowing Covid-19 transmission rates over the past two years. But he added that increased hand-washing practices caused "significant harm" to the environment.

"Importantly, the work shows that sanitising gels cause less harm than soap-and-water practices, with isopropanol-based gels in particular leaving a relatively lower impact," Duane said. "This is useful information for reducing further environmental damage but also underlines the need for new gels that are more environmentally friendly."

• According to the World Health Organisation, hands that are visibly soiled should be washed with soap and water, while sanitising gels may be used when there is no visible soiling present on the hands.