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Biology 103
2001 Third Web Report
On Serendip

Can We Get Too Clean?

Millicent Bond

Dial antibacterial soap advertises that it is "over 10x more effective at killing disease-causing germs than ordinary liquid hand soaps"(1). To the average consumer a soap with the ability to kill more germs seems to be more effective. But is a more powerful antibacterial soap always better? Various studies suggest that antibacterial soaps can be harmful and may lead to problems like super bugs, dry skin, and hand eczema. According to current research antibacterial soaps are no better than traditional soaps when it comes to house hold use.

Antibacterial cleaning agents have fast become a popular alternative to traditional cleaning products. These soaps, shampoos, dishwashing detergents, and toothpastes are marketed as antibacterial products and have become popular household items. In fact 75% of liquid soaps and 30% of bar soaps on the market are considered antibacterial(2). These antibacterial products are so popular because they are intended to decrease bacteria. They wipe out more germs than regular soap. This means that they should decrease a person's chance of getting sick. As Janet Donohue of www.germsmart.com suggests "they kill germs, thus breaking the cycle of infection"(3). In addition to killing germs some antibacterial products are easier to use than traditional soap and water. For example, there are many hand sanitizers that do not require water. A user simply applies the soap to his hands and the dirt "disappears". These products seem magic, but as we know magic does not exist in science.

To fully understand how antibacterial products work one must learn how soap works. Soap consists of an acid and a base(4). The acid known as triglycerides mixes with the base sodium hydroxide. This combination makes the fatty acid separate from the triglycerides and fuse with the hydroxide ions(3). This forms the salt we know as soap. Soap has the ability to decrease the surface tension of water. It also binds to dirt and germs. These two qualities allow soap to cling to unwanted dirt and wash away easily.

While soap does a good job of removing dirt and germ it does not kill all of the bacteria. Antibacterial soap has the ability to wash away more germs and bacteria. Antibacterial soaps are made with triclosan and some include triclocarbon. These agents are antibacterial and target certain bacteria. This means that antibacterial soaps are stronger than the traditional soaps. Scientist believe that "triclosan targets a gene in E. Coli bacteria"(1). The intention is to prevent the bacteria from reproducing. This limits the amount of bacteria present on a person's skin after using an antibacterial soap. In theory this helps decrease illnesses.

Despite it's intentions, triclosan may cause serious problems for its users. Although it was once believed that triclosan "attacks bacteria membranes and kills indiscriminately...much like a bomb"(5), new research suggests otherwise. Studies by various scientists such as Stuart Levy, Charles Rock, and Richard Heath have shown the negative attributes of antibacterial products. The triclosan does not kill off all of the bacteria. It only kills weak bacteria leaving the stronger bacteria to reproduce. As Rock and Heath found "triclosan, inhibited by an enzyme in fatty acid biosynthesis, produces a gene called fabl and that mutation in fabl gene causes resistance to bacteria"(4). This implies that antibacterial products are strengthening bacteria rather than killing them off.

One problem associated with antibacterial products is the creation of super bugs. It is the nature of bacterium, like any living organism, to adapt so that they can survive. The bacteria with the ability to survive antibacterial soaps reproduce making bacteria as a unit more powerful. Some fear that after years of killing off weak bacteria all that will be left is the powerful bacteria that we cannot kill off. The sterile environment created by the use of antibacterial washes might be more conducive to the well being of more powerful germs(6).

In addition to strengthening bacteria antibacterial soaps are believed to cause the spread of certain illnesses. Dermatologists blame the overuse of antibacterial soap for the spread of certain skin diseases. The components of the antibacterial soaps wipe away more bacteria and tend to be harsh on skin. People use the antibacterial soaps, which than dry out the skin and can lead to open sores. They then shake the hands of other people and spread more bacteria than they would have had they used a traditional soap. As Dr. Marianne O' Donoghue claims, "There is nothing quite as good to spread bacteria as hand eczema"(7). Though this is rare and usually happened to people who washed their hands between twenty and twenty-five times a day, the components of antibacterial soaps are harsh on the skin.

In response to the recent studies conducted to expose the problems associated with antibacterial soaps The Soap and Detergent Association (SDA) and the Cosmetic, Toiletry, and Fragrance Association (CTFA) have tried to convince consumers that antibacterial soaps are not to blame for stronger strands of bacteria(2). They claim that antibiotic is to blame for the problems. The CTFA and SDA tell "consumers [they] should continue to use antibacterial personal care/cleaning products in the home with confidence"(7). They point to the United States Department of Health and Human Services report on labeling antibiotic as defense8. The report argues that the over use of antibiotics is causing more powerful bacteria to survive. While the SDA and CTFA may be right about the overuse of antibiotics, there has never been any proof that antibacterial soaps prevent sickness on a consumer level any more effectively than traditional soaps. These modified soaps have no protection against viruses, which cause many illnesses as well.

The SDA and CTFA do make an important point about the use of antibacterial soaps in the medical profession. Hospitals use antibacterial cleaners to reduce bacteria in an environment that is encouraging for bacteria. Under these circumstances the antibacterial products have been effective. The problem is that the bacteria killing soaps are so readily available to consumers that they are being abused. The combination of the widespread use antibacterial soaps and the over use of antibiotics could cause a spread of super bugs. The American Medical Association has begun to question the use of antibacterial soap among doctors(2). It would be more effective to question the home use of these soaps.

In conclusion antibacterial soaps are more trouble than they are worth. They are useful in the medical world, but in the home they are no more effective than traditional soaps. Many researchers believe the problem of germs spreading lies in improper hand washing(1). Most people don't wash their hands for long enough and as a result germs are spread through hand shakes and everyday contact. Studies of antibacterial soaps show that there is no absolute way to prevent the spread of bacteria. Rather than trying to wipe bacteria out we should work on limiting our exposure to too many harmful bacteria with traditional soaps, shampoos, dish detergents, and toothpaste.

WWW Sources

1)How Stuff Works Site, This site gives answers to simple science questions.

2)Health at OZ site,

3)United States Health and Human Services, This is a copy of the report given on antibiotic

4), Germ Smart site,

5), Doctors Guide,

6) Nurse Week Article ,

7) MSNBC Report , Buissness Journal,

) Dial Soap Site,




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