Chemist Mom Reads the Label: Hand Sanitizer

Health & Wellness on 03.21.11
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 Photo: colon+right-bracket/Creative Commons

Does your day care insist on using hand sanitizer, even though you would prefer to stick with soap and water? Here we take a closer look at the ingredients on the label of one popular brand, and offer some explanations to put your mind at ease, as well a peek at some of the many issues that consumer product formulators need to keep in mind when selecting the chemical ingredients they use.

As you will see, reading chemical labels is no simple exercise. The information on the web is a good starting point, but also contains a lot of mis-information (though usually on the over-protective side of things). Of course, we have reduced reams of studies to a couple of remarks, trying to capture the most important issues. Hopefully these comments will reduce 'chemically' from outright confusing to merely complicated. You will be the best-informed parent at the day-care debates over hand sanitizer!

So let's dig in. Ingredients listed on the popular hand sanitizer marketed under the tradename Purell include:

Ethyl Alcohol 62% w/w, Water, Isopropyl Alcohol, Glycerin, Carbomer, Fragrance, Aminomethyl Propanol, Propylene Glycol, Isopropyl Myristate, Tocopheryl Acetate.

Ethyl Alcohol 
More commonly known as ethanol, ethyl alcohol puts the punch into wine, beer, and vodka. It has many known negative health effects, but is an effective germicide and safe to use when applied to the hands. In fact, it is the opinion of this mom that alcohol-based hand sanitizers are better than the alternatives, in spite of the risks to toddlers getting away with a sip or two of their hand sanitizer. Control the risk with good supervision, and contact a doctor immediately in case you suspect your toddler got ahold of the hand sanitizer behind your back. Conclusion: the safest option, less risky than some of the diseases it protects against.

Isopropyl Alcohol
Isopropanol, contained in Purell at 5%, most likely serves the combined purposes of discouraging teenagers from drinking the stuff, improving the rate of evaporation, and supporting the germicidal effectiveness of the ethanol. Isopropyl alcohol is changed into acetone inside the body; acetone is naturally produced in the body as well, so is not a particular threat, but it can worsen the intoxication effects of ethanol by blocking the path your liver uses to clean alcohol out of your bloodstream. Conclusion: we would not add isopropanol to our home-made product, but it is safe to use on hands, with the caution about poisoning noted above.

Also known as glycerol, this natural part of your body's chemistry is of low toxicity, and is added to many foods. Reports on the web indicating potential for kidney damage should not cause you to worry; these are based on a misunderstanding of medical reports. In some medical testing, glycerin is used to cause (induce) kidney failure. But it is not the glycerin that is damaging the kidney, it is the side effects of muscle death which injection glycerin directly into the muscle causes. The danger of glycerin in a hand sanitizer for children is that it is sweet. Anything that encourages young children to taste a chemical product should be avoided. Conclusion: a safe ingredient, and probably not enough sweetness to make hand sanitizer attractive to toddlers who will hate the taste and irritation of the alcohol.

Carbomer is also basically harmless. Glycerin and carbomer are probably added to improve the consistency of the product.

Whenever you see this industry code word, you are taking  a gamble. It is a secret identity for a lot of chemicals which are considered safe at the very low concentrations found in the final product. But concern is increasing that the sum of exposure to these chemicals in the average daily routine, as well as the potential for harmful effects even at very low concentrations. It is also a common source of allergic reactions to consumer products. If your child reacts to hand sanitizer with redness or irritation after a period of using it without trouble, you should look for products specifically formulated for "sensitive skin." Conclusion: do you trust the company you are buying from? Then the fragrance they use can be trusted too.

Aminomethyl Propanol
This alcohol can irritate the skin and eyes. It is certainly present at amounts less than 10%, at which concentrations it will likely not cause irritation. Conclusion: safe as used.

Propylene Glycol
Some sources indicate that this common skin conditioning agent may be carcinogenic, mutagenic or have reproductive effects. But a comprehensive review of the test data by the OECD in 2001 ranked the chemical of low concern and found that long term studies provided sufficient evidence to rule out these effects.

Propylene glycol has also been accused of being a sensitizer. But studies have shown that if there is any allergy-inducing potential of propylene glycol, it is very weak. In susceptible people, PG can cause "non-immunological contact urticaria," which sounds scary, but just means a temporary redness with swelling. It is this reaction which may account for the "false positive" determination of sensitizing effects. Nonetheless, the body of evidence available do suggest that certain people are susceptible to either an allergy or to be easily irritated by propylene glycol.

The conclusion? Many studies, even at relatively high dosages and with human subjects, exist. This gives a relatively high degree of confidence to the finding that this chemical is safe as used. Nonetheless, a small percentage of people may react badly to propylene glycol, with redness and swelling as symptoms. If your child shows redness or swelling after using any cosmetic product, stop use immediately and consult your pediatrician on substitutes.

Isoprpropyl Myristate
Isoprpropyl Myristates is distilled from coconut oil. It is a common ingredient in skincare products for two reasons. First, it helps to dissolve waxy substances like lanolin that smooth and preserve the skin. Second, it helps the ingredients in a skin treatment penetrate the skin. This can present a danger: the isopropyl myristate can help transport toxins as well as beneficial chemicals into the skin. As a precaution: only use one skin product at a time. Presumably, the chemist that chose to use isopropyl myristate is confident it presents no hazard in this product; but no one has reviewed the combination with other products. Isopropyl myristate itself may irritate skin and eyes, though not at the concentrations in hand sanitizers, but is otherwise not harmful to humans. Conclusion: we would not use a penetration enhancer in our home-brew, but it should be safe as used.

Tocopheryl Acetate
Under the common name Vitamin E acetate, this chemical seems less scary. But it has also been linked by some sites to cancer. In fact, studies show that Vitamin E acetate uses its antioxidant properties to fight cancer. Most likely, the citation of these studies in public databases under cancer findings was not understood to indicate a beneficial protection. Conclusion: safe, even beneficial, as used.

Two Ingredients *not* in Purell
Triclosan, Benzalkonium chloride. These two ingredients do not show up on a Purell label, because the alcohol is doing the job ofkilling the bugs on your child's hands. Yes, you are trading a risk of alcohol poisoning against the risks of these bactericidal drugs. We think the trade-off is the right one, but every parent has to do what they think is best for their child. You should be aware thatpediatric studies involving children of 6 months to five years of age have been designed with alcohol-based hand sanitizers, indicating that the medical community also deems this safe. If you are still in doubt, ask your pediatrician.

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