Top Screwups Doctors Make and How to Avoid Them: Health care screwups are one of the leading causes of death in America, killing as many as 750,000 people annually. That’s more than heart attacks or cancer. And yet most people don’t know this, including most physicians. From diagnostic disasters to deadly drug interactions, the bestselling authors of The People’s Pharmacy expose the alarming epidemic of medical mistakes in America—and offer a lifesaving prescription to make the healthcare system safe again. Only $26.00 +s/h
Was this information helpful? Average rating: 4.6/5 (5 votes)
What do you think? Click the stars to vote!
If you have more to say, post a comment below!
Q. In your column you said that warm water is no more effective than cold for removing germs. You are way off the mark. We wash to remove germs, not kill them. Dirty hands are oily and oils are more soluble in warm water. So is soap. Warm water works faster and is more effective than cold water for rinsing off germs. Even my third-grader knows better than you.
A. Several other also readers took us to task for suggesting that warm water is no more effective than cold for removing germs. To try to get a more objective answer, we checked with Charles Gerba, PhD, Professor of Environmental Microbiology at the University of Arizona. He is one of the country’s leading researchers on germ contamination.
Dr. Gerba told us that he has “not seen studies comparing hot vs. cold water for hand washing. Warm water might be somewhat more effective, but the difference is probably so small as not to make much difference. Washing is too quick for the heating to kill much or the soap to dissolve better.”
To wash hands well, wet the hands, apply soap and rub the hands together vigorously for 15 to 20 seconds. Then rinse the lather off thoroughly.
Was this information helpful? Average rating: 4.6/5 (5 votes)
What do you think? Click the stars to vote!
If you have more to say, post a comment below!
I had a baby in the NICU and when I went to see him I had to do a 3 minute wash. They said to use antibacterial soap and wash for 3 full minutes with warm water because anything less than that is just wetting the germs, not killing them.
Tsk, tsk, Dr. Graedon. You have forgot your Chemistry 101. I am quoting from 7th edition, Basic Chemistry by Seese & Daub, the old text for the introductory chem couse I teach at Fayetteville (NC) Technical Community College for students to meet the chemistry requrement for entering a health science curriculum. From page 319: Some substances have greater surface tension than others because of the attractive forces in these substances are greater(mercury vs water. Alcohol is often used to prepare an area for medical treatment because it has a low surface tension and can easily penetrate into a wound to cleanse the area. One reason for the cleansing action of soap solution is that it lowers the surface tension of water, allowing the solution to penetrate into the skin creases to clean out grease that holds dirt in place. As the temperature increases, the aaverage kinetic energy of the molecules increases, and this increase in energy tends to overcome the attractive forces among molecules. As a result, the surface tension decreases. As you are aware, you can wash your hands more efficiently in hot water than in cold, in part because of the decreased surface tension in hot water. The cleaning powder we added to water in high school labs did not make suds but was an effective cleaner because it lowered the surface tension of the water. Hope this helps.
Whether or not warm water makes a minute difference in how clean one's hands get is not as relevant as the fact that one is more likely to wash one's hands for a LONGER period of time if the water is comfortably warm.
Michaels, B, et al. (2002) Water Temperature as a Factor in Handwashing Efficacy. Food Service Technology: 2; 139-149.
This article will answer the question. But I will explain a little bit of the reason why.
I am heading up some research on this subject and the scientific data suggest that temperature does not have a significant effect on the efficacy of handwashing. I have performed studies replicating that of Barry Michaels in his Food Service Technology article. I have written an extensive literature review on the relationship of temperature and hand washing efficacy. My colleagues and I have come to the conclusion that hot water does not provide a public health benefit but does use a profound amount of energy. By reducing the nations use of hot water during handwashing it may be possible to save up to 350,000, 400,000, and 1,500,000 metric tons of carbon per year in the Food Retail Industry, Health Care Industry, and General Public respectively.
Even though temperature may have an effect on solubility there are two important factors that I will touch on that separates handwashing from other mediums. First, unlike other substances, the skin is an organ that is actively trying to protect the body. Water, a mild irritant, hinders the skins ability to defend itself and the body. Second, when one washes their hands with soap a process called emulsification occurs. The complex process of emulsification allows non polar solvents to dissolve into polar solutes. Unlike substances in solution, there is not a linear relationship like with solubility during emulsification. The optimum temperature of emulsification varies on the chemical make up of the medium (usually soap or sodium laurel sulfate). Research has determined that the optimum temperature for emulsification is between the cloud point and the phase inversion temperature. This temperature does not necessarily occur at the highest possible temperature.
There are several other reasons why temperature is not a factor. But there this is not the forum for that. Be sure to look for a publication on this matter within the year. I have been working on it for a while now.
I have to disagree a bit and add a point that some have left out and the simple fact that most people do not even process is friction... that is what really matters. Vigorously does not mean fast, it means with force. Washing in cold water kills germs, and it also gives the added benefit of GREATLY reducing dry chapped, cracked skin. If you don't think so, try it for 7 days, you will notice the difference! Remember FRICTION!