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Careful, you can be too clean

Think of all the things your hands touched so far today: the railings, doorknobs, elevator buttons. How dirty did your hands get? And how clean should they be?

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Think of all the things your hands touched so far today: the railings, doorknobs, elevator buttons.

How dirty did your hands get? And how clean should they be?

Given the plethora of nasties that abound on these surfaces, many people turn to antibacterial soaps. But one ingredient, triclosan, has come under increasing scrutiny because of the potential for interfering with hormone systems. Triclosan also is in wipes, creams, toothpastes, and more. One survey found that 76 percent of liquid soaps and 29 percent of bar soaps contained triclosan or its close relative, triclocarban. The National Health and Nutrition Examination Survey has found measurable levels of triclosan in 75 percent of the population.

The U.S. Food and Drug Administration has had triclosan on its radar for decades but has not ruled on its safety. Prompted by a 2010 civil suit brought by the nonprofit Natural Resources Defense Council, the FDA must issue regulations by September.

For perspective, we turned to Gary Emmett, a pediatrician at Nemours duPont Pediatrics at Thomas Jefferson University Hospital and professor of pediatrics at Jefferson. For about a decade, he was the hospital's pediatrics hand-washing champion - its chief advocate and watchdog. Emmett figures that, on a typical workday, he washes his hands at least 40 times, sometimes as many as 80. Do the math, and he's easily washed his hands more than half a million times.

He says triclosan has been an issue before the FDA at least since he was a medical resident in the 1970s. "There is a lot of economic and political pressure because a lot of companies make money off this stuff,'' he told us. But in terms of public health, he said, the central question is more straightforward: "How much is too much, and too much is much easier to do with a baby than with a big person."

Given all the bacteria around and on us, antibacterial soaps would seem like a good idea.
This is actually a wider issue. How clean is good for you? Triclosan and triclocarban do go through your skin. They are fat-soluble. If you overuse them, you can get significant blood levels. And the smaller you are, the more potentially dangerous they are, because children have much larger skin surface per unit of weight than adults. A newborn has seven times the amount of skin surface per pound than an adult does. That's why they get cold and hot so fast.

The big problem is that triclosan interacts with two important classes of hormones in your body: the thyroid hormones and the sex hormones. The chemicals attach at the same sites that those hormones do and can block those hormones from working.

So they can interfere with your thyroid function, the function that makes your body hum. If you don't have enough thyroid function, you're tired all the time. You don't fight off infections as well. A lot of the normal things about sleep and wakefulness are messed up. If you interfere with testosterone, that can make your muscles flabbier and can interfere with male sexual function.

You would have to get a lot of triclosan on your skin to cause interference, but there are people that wash their hands with this stuff 20 and 30 times a day.

So what do you do as far as hand-washing in the hospital?
We do not use triclosan in the hospital. We just have to wash our hands too much.

When I do rounds in the nursery, where I will wash my hands 40 or 50 times in a morning, I use soap and water as much as possible.

When I don't use soap and water, I use alcohol-based products. The problem with using alcohol-based products is, one, they kill your hands. I find if I just use alcohol-based products, no matter how good the quality - and it's pretty darn good - my hands feel awful and get rashes by the end of a full day in the nursery. If I intersperse using the alcohol-based products with plain old soap and water, I do much better.

The thing that pediatricians worry about with alcohol-based products is they have an amazing amount of alcohol in them. It's not the same alcohol that's in bourbon. But it is, in large quantities, really toxic if you ingest it. Adults are not going to do that. But little children, especially toddlers, will ingest almost anything. And for a 22-pound child, the typical weight of an early toddler, two ounces of alcohol-based cleanser can be a toxic dose.

As you mentioned, is there such a thing as being too clean?
Some degree of cleanliness is very good for you, health-wise. There are interesting theories about why early modern Jews in Eastern Europe had a much lower infant mortality rate than their neighbors. The theory is that, because of religious requirements, observant Jews have to wash their hands before every meal and before food preparation. And it seems to have been that washing your hands four times a day versus essentially none seems to have really helped mortality rates.

But it turns out that being overly clean is not good because we need our friends, the bacteria. Every individual has a microbiome, which is a vast number of bacterial cells, more than 500 species, that inhabit the skin and gut and mucous membranes. In fact, every individual has eight or nine times the number of bacterial cells than they do of human cells. So you can say that the best of us are only about 10 percent human.

You need that normal microbiome to be healthy. If you wash too much and you clean all the germs off the surface too much, you don't get those normal germs you need. We now know that cleaning things off too much, especially during the early days and months of a child's life, can result in the child not acquiring a healthy microbiome.

Are there any specific examples of being too clean?
Long ago, people were worried about getting infected umbilical cords in newborns. And they used to put on harsh chemicals - this purple dye that was antiseptic - to stop the cord from getting infected. This made sense because in a world without clean water, which was true of everywhere in the 19th century, infected umbilical cords could be deadly. But in the modern era, when water is for most of us clean, it turns out that the cords - which are supposed to come off because normal bacteria that occupy the umbilical site make the cord dry up, fall off, and seal the opening - started hanging on longer and longer. The normal time for a cord to come off should be about seven to 10 days. In babies who really got their cords scrubbed, it would be five, six, seven weeks. Since the cord has a vein and two arteries that are connected directly to your heart, liver, and spleen, it became a route for bad germs to get in. So now, if you have a baby in a modern baby-friendly hospital, they don't put anything at all on the cord.

We're learning all kinds of interesting stuff which we didn't know even a few months ago. For instance, babies who suck their thumbs or use a pacifier, both of which you must admit are fairly disgusting habits, are less likely to get sick when they go to day care, and are less likely to get asthma later in life. So you need germs. The body wants germs. But they have to be the right germs.

In the end, what is your best advice for how often people should wash their hands, and what's the best technique?
Wash your hands before you eat, with soap and water. Wash your hands after you go to the bathroom, with soap and water, although probably running water is pretty good by itself. If you get your hands physically dirty, non-water cleansers do not work. If you actually get stool or snot or tears on your hands, you have to use soap and running water.

But all soaps, even ones for sensitive skin, if you use them too much, can dry the skin, and dry skin is more likely to get infected. So you can make almost anything dangerous if you work really hard at it.

More important than that, probably the number one source of infection is a person touching his or her own nose or mouth. Germs that are happy in the nose and mouth are not happy if they get into cracks in the skin and other places, where they can cause a lot of damage. So if you can figure out how to keep your hands away from your nose and mouth, there is nothing better you can do for yourself.

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