Soap and water are fine. The FDA says you don't need most anti-bacterial products at home.

It's a comforting time to be a germ freak. In addition to anti-bacterial hand soaps and shampoos, the microbe-averse can buy bacteria-fighting clothes, toys, towels, sheets, sponges, mops and even pens.

Never mind that trillions of bacteria reside on our skins and in our mouths and intestines. Or that some exposure to germs helps us develop healthy immune systems.

In 2004, Americans spent more than $540 million on anti-bacterial soaps, hand cleaners and detergents that contain chemicals such as triclosan to kill germs, though a Food and Drug Administration panel found that they are no better than soap and water.

The issue isn't just that products impregnated with germ-fighting chemicals are a waste of money. It's not even that they could promote the growth of antibiotic-resistant bacteria, something the Soap and Detergent Association maintains happens in the lab but not in the real world.

The association says people confuse anti-bacterial with antibiotic. If there were a link, the organization says, it likely would have been seen in settings such as hospitals.

More disturbing, the germ-fighting chemicals found in anti-bacterials, namely triclosan and triclocarban, are turning up in fish, breast milk and wastewater. Then they are released into the environment through municipal sludge, which is recycled and spread on agricultural fields.

This concerns researchers such as Rolf Halden, assistant professor at the Center for Water and Health at Johns Hopkins Bloomberg School of Public Health.

The U. S. Geological Survey has shown that triclosan – which mimics the thyroid hormone and is commonly added to soaps, toothpaste, deodorant, dog shampoo, cutting boards, clothing, toys and other anti-bacterial products – is in 60 percent of U.S. waterways investigated.

Dr. Halden's studies show a similar dispersal of triclocarban, which is found mostly in deodorant bar soaps.

Though the amounts turning up are minute, a recent study has shown it's enough to disrupt thyroid function in frogs. Equivalent data on humans isn't yet available.

As ingredients in products, the chemicals aren't necessarily harmful to humans, scientists say. But evidence is mounting that "these chemicals are remarkably persistent and possibly bioaccumulating not only through products [applied to the skin] but environmentally through drinking water and potentially contaminated crops," said Dr. Halden, a member of the FDA panel that looked at the benefits and hazards of antiseptic hand soaps.

Also, anti-bacterial soaps don't prevent colds or flu, which are caused by viruses, not bacteria. And most experts say that unless you're in a hospital environment, using products with triclosan – a biocide that can destroy biological structures at random – is like using a jackhammer to kill an ant.

The American Medical Association has opposed routine use of anti-bacterial soaps since 2002. This year, the Canadian Pediatric Society asked parents to stop buying anti-bacterial products and to use soap and water to wash toys, hands and household items.

There is a place for anti-bacterial products: a hospital. Think twice about using them in your home every day. Soap and water are just as effective. And cheaper.