Recent intense media scrutiny including hidden camera video in Canadian hospitals has exposed an alarming truth: there is a shocking lack of diligence among the general public, many visitors to health-care facilities and, most disturbingly, the majority of doctors and other health-care workers with respect to frequent and effective hand-washing.

But as the U.S.'s National Handwashing Week drew to a close this past weekend, two recent studies are drawing attention to some previously unknown hidden health risks associated with increasingly vigorous and frequent hand-washing, with newer, chemical laden anti-bacterial soaps and sanitizing gels.

This past August a University of Michigan study in the journal Clinical Infectious Diseases showed that antibacterial soaps available to the public might convey no health benefits over plain soap and water. Indeed the study showed that these soaps also were no more effective at simply removing bacteria from the skin, not to mention having questionable antibacterial action.

Most disturbingly this study concluded that in addition, these often more expensive soaps may in fact render some commonly used antibiotics, like amoxicillin, less effective in the long-term. According to Allison Aiello of the U-M School of Public Health and her team, because triclosan (the main active ingredient in many antibacterial soaps) works inside cells, it may cause some common bacteria, such as e-coli, to become resistant over time to common antibiotics. This particular active ingredient might be causing bacteria to evolve and change, giving them mechanisms to survive our special soaps and gels, and indeed, our vital antibiotic protection and treatment for infections.

In addition to soaps, triclosan is often added to products such as acne treatments, mouthwash, toothpaste, household cleaners, and has even been infused into a number of consumer products, such as kitchen utensils, toys, bedding, socks, and trash bags.

Health Canada has also registered 1,200 cosmetics that include the ingredient triclosan.

The U-M study did not look at the effectiveness of other active ingredients, such as the alcohol found in many hand gels, so conclusions cannot be drawn about all products, but the study does question the value of spending extra money for products that contain triclosan, and suggests the inspection of labels if you are concerned. Indeed, the same health benefits might be had by simply using normal soap, and proper, effective washing methods.

Yet another alarming concern has recently been raised regarding antibacterial soaps and gels. As early as two years ago, in 2006, a study on frogs showed that the active ingredient triclosan discussed above was associated with so-called "endocrine disruption." The endocrine system is an integrated system of small organs which involve the release of extracellular signaling molecules known as hormones. This system is instrumental in regulating metabolism, growth and development and puberty, tissue function, and plays a part also in mood. Endocrine disruption is a process whereby chemicals from outside the body mimic naturally occurring hormones, and can cause a break-down of the normal or proper functioning of hormones in the body, leading potentially to any number of health problems including cancer, reproductive failure and developmental anomalies.

An example of an endocrine disruptor most of us are familiar with is the birth control pill, but new research is revealing that many chemicals we use every day might in fact behave in surprising ways, and act as endocrine disruptors.

This brings us back to hand-washing. Last week a new University of California (Davis) study concluded that a common antibacterial chemical added to bath soaps can alter hormonal activity. This chemical, triclocarban, has been shown to have these hormonal effects in rats. But, most importantly in this new study these effects were also demonstrated in human cells in the laboratory and the chemical was creating the effects by a previously unknown mechanism.

Unlike most endocrine disruptors triclocarban was found to increase the effects of testosterone on cells, and led to grossly abnormal growth of organs, such as the prostate gland, that are moderated by testosterone

Like triclosan, products containing triclocarban are widely used in household and personal care products including bar soaps, body washes, cleansing lotions, wipes and detergents. Triclocarban-containing products have been marketed broadly in the United States and Europe for more than 45 years; an estimated 400 000 kilograms of triclocarban are imported annually for the U.S. market.

A Johns Hopkins study has found that triclocarban persists in the environment in wastewater, produced when we rinse our hands after washing , and can remain active in the environment for an unknown period of time once introduced.

As Bill Lasley, an expert on reproductive toxicology and one of the authors of the UC (Davis) study said, "Our mothers taught us to wash our hands well before the advent of antimicrobial soaps, and that practice alone prevents the spread of disease." And Dr. Lasley is correct: antiseptic practices, even hand-washing, were virtually unknown, especially amongst physicians, until introduced and energetically endorsed and enforced in the nineteenth century by such visionaries as Joseph Lister. They are integral to the maintenance of good health and the prevention of the spread of disease today, especially in health-care facilities.

Consumers should consider carefully checking the labels of the products used on a daily basis at home and at work, and perhaps consider whether they need antibacterial products for their daily lives, or whether just plain old soap and water will do.