More settled science: Hot water is more effective than cold water for handwashing, or not

Hot water still sacrificed by Palm Beach County budget squeeze

The Health Department doesn’t consider hot water necessary for hand washing, according to John O’Malley, the health department’s director of the division of environmental public health.

Really? - The Claim - Always Wash Your Hands With Hot Water, Not Cold - Question - NYTimes.com

In its medical literature, the Food and Drug Administration states that hot water comfortable enough for washing hands is not hot enough to kill bacteria, but is more effective than cold water because it removes oils from the hand that can harbor bacteria.

But in a 2005 report in the Journal of Occupational and Environmental Medicine, scientists with the Joint Bank Group/Fund Health Services Department pointed out that in studies in which subjects had their hands contaminated, and then were instructed to wash and rinse with soap for 25 seconds using water with temperatures ranging from 40 degrees Fahrenheit to 120 degrees, the various temperatures had “no effect on transient or resident bacterial reduction.”