Cool news about handwashing
A recent Rutgers-New Brunswick university study has found that hot water is not essential for handwashing — washing hands in cool water for 10 seconds was found to be just as effective in removing bacteria as washing in hot water.
To establish this assertion, Rutgers researchers put high levels of a harmless bacteria onto the hands of 21 participants and asked them to wash their hands in 15.5°C, 26°C or 37.7°C water using 0.5, 1 or 2 mL volumes of soap. This process was repeated multiple times over a six-month period.
Washing the hands for 10 seconds significantly removed bacteria from the hands at all of the water temperatures.
“This study may have significant implications towards water energy, since using cold water saves more energy than warm or hot water,” said Donald Schaffner, distinguished professor and extension specialist in food science at the university.
The amount of soap used did not affect the results, but the researchers believe that more research could be useful to establish the optimal type and amount of soap that reduces bacterial loads. This information would be particularly beneficial in the foodservice industry.
Currently the FDA guidelines recommend that water for handwashing should be 37.7°C in food establishments and restaurants, but it seems this may not be an essential criterion.