The Truth about Hand Sanitizers
Washing the hands with warm, or hot, water and soap is the best methodology for preventing the spread of infectious diseases, as this approach removes from the hands the oils which can harbour dangerous microbes.
However, hand sanitizers also have their place (especially in public venues where soap and water are not available) as many sanitizers are very effective at killing microbes. That being said, it is important to be aware that some sanitizers can have potentially dangerous side effects, when used consistently, and only certain types of sanitizers can kill viruses. As well as examining the basics on sanitizers, I will also look at the importance of cleaning under the fingernails.
The Two Types of Sanitizers
Hand sanitizers are divided into those which are alcohol-based, and those that are alcohol-free.
The alcohol-based ones (between 60 and 95% alcohol) are more effective than the non-alcohol versions. The non-alcohol versions will still reduce microbe levels, but not as effectively as the alcohol-based ones.
The first generation of alcohol-free sanitizers were based on the antibacterial agent triclosan, (also used in soaps, cosmetics, and some toothpastes), which proved to have dangerous side effects.
Triclosan, while effective against bacteria, also contributed to causing antibiotic resistance in bad bacteria, by also killing good bacteria on the skin. In a 2011 study (done at the U.S. Centers for Disease Control and Prevention), researchers found those who were most likely to use hand sanitizers, over soap and water, for hand washing, were nearly 6 times more at risk for catching norovirus (which causes acute gastroenteritis).
Triclosan has also been linked to impairing immune function, clearly something to be avoided if we are trying to keep viruses at bay. Researchers at the University of Michigan School of Public Health found that children and teens with higher levels of triclosan in their bodies were more likely to be diagnosed with hay fever and other allergies.
Finally, animal studies indicated that triclosan could negatively affect hormones, as it is a xenoestrogen, having a tendency to bind to estrogen receptors, and interfere with natural estrogen binding.
In April, of 2019, the American Food and Drug Administration banned 28 antimicrobial ingredients, including triclosan, from being used in over-the-counter hand sanitizers sold in the US, based on the above-mentioned concerns. (Source)
So, why am I discussing triclosan, if it is banned from the marketplace? Well, even though triclosan is banned in the U.S., it has not yet been banned in Canada. Health Canada still allows triclosan to be used in some cosmetic products if the concentration is below a specified level. Products containing higher levels of triclosan must be approved through a formal drug application process.
"Health Canada has approved 64 marketed drug products with a Drug Identification Number that contain triclosan. These are not all hand sanitizers ― some are soaps, hand washes and toothpastes." (Health Canada)
The horrible irony is that, while Health Canada has concluded that triclosan is safe for us to use, the Environmental ministries have determined that it is highly toxic to fish and aquatic life, affecting "growth, reproduction and survival". The ministry for Environment and Climate Change reports that triclosan is “continuously present” in the Canadian environment (and is also found in rivers and lakes throughout the world).
Therefore, triclosan has recently been added to the official list of toxic chemicals under the Environmental Protection Act, and the federal government is currently working on a program that would require companies to reduce their triclosan by 30%, by May 2020. (Source)
New generation alcohol-free hand sanitizers now usually contain quaternary ammonium compounds (most commonly, benzalkonium chloride) instead of triclosan (and related compounds). Benzalkonium chloride is primarily used as an antimicrobial agent and preservative, though it also serves as a surfactant (detergent), which means it can work in a soap-like manner if water is also used.
“It has been well-established that benzalkonium chloride is not genotoxic nor does it display tumorigenic potential, but safety concerns have been raised in local usage such as for ocular and intranasal applications.” (So, don’t put it in your eyes or nose.) (Study)
Nonetheless, with regular usage, it is not uncommon that one might have an allergic reaction to benzalkonium, therefore discontinue use if symptoms arise. Symptoms of an allergic response can include red, swollen, blistered, or peeling skin, rash and/or hives. For those highly chemical sensitive symptoms are worse, including trouble breathing, swallowing or talking, swelling of the face, lips, mouth, tongue, or throat, or tightness in the chest and wheezing.
Given that so many chemicals commonly used in cosmetic products are xenoestrogens (which disrupt hormones in an unhealthy manner, especially in children), we also should read the ingredients on our sanitizer to ensure it is free of other potentially toxic compounds.
If your hand sanitizer is scented with anything other than natural essential oils from plants, then it likely contains toxic chemicals. Companies are not required by law to disclose the ingredients which make up their scents, and these fragrances often are made up of dozens of chemical compounds.
Synthetic fragrances usually contain phthalates, another type of xenoestrogen which mimics hormones, and can alter genital development in infants and children, and lead to cancer in adults. (Source)
So, the takeaway is: read the ingredients of your hand sanitizer, especially if you live in Canada (or are buying from “Dollar Stores”).
Alcohol Based Sanitizers
The best choice for hand sanitizers currently appears to be those which are alcohol-based. Alcohol at a level of 60%, or more, will effectively kill bacteria and fungi, while at less than 60%, it may only reduce the growth of germs, rather than outright killing them.
The big advantage of the alcohol-based version is that, at 60% or more, alcohol will also destroy many viruses including the influenza A virus, rhinovirus, hepatitis A virus, HIV, and Middle East respiratory syndrome coronavirus (MERS-CoV). Alcohol does this by destroying the protein envelope that surrounds and protects viruses, which is essential for viruses to survive and replicate.
Even alcohol-based sanitizers can include fragrances, which, again, can contain toxic chemicals, so choose one that has no fragrance, or only uses natural, essential plant oils. These products also commonly contain glycerin, a safe compound added to help prevent the skin from becoming too dry as a result of repeated application of alcohol.
Back to Washing
Now, even the superior alcohol-based, 60% and stronger, hand sanitizer, does not kill all types of germs. For dealing with norovirus, Cryptosporidium (a parasite that causes diarrhea), and Clostridium difficile (bacteria which cause bowel problems and diarrhea), hand washing has proven far more effective. (Source)
And if hands are visibly dirty, it is more effective to wash with soap and water than to use even an alcohol-based hand sanitizer. As well, if one has just coughed or sneezed into their hands, hand sanitizer will not be sufficient to disinfect them, because the mucous contamination protects the microbes from the killing agents.
It has been well established that the most efficient way of reducing risk of spreading and contracting any virus is to wash the hands with soap and water, regularly, and to avoid touching the face as much as possible.
Finally, a word about fingernails. Did you know that fingernails harbour the most bacteria found on the human hands? (Source)
Back in the 90s I recall a doctor who had a book promoting the idea that the majority of pathogens enter the human body from under the fingernails. He even had a line of products designed to keep fingernails sanitized. Though I cannot find any of his original material, his thesis does hold true.
Thus, fingernail hygiene must be part of our sanitizing regimen (and a point to note is that artificial fingernails harbor a greater number of pathogens than natural nails). It is also important to ensure that we wash thoroughly, or sanitize, the skin surrounding the nails.
Ideally, nails should be kept clean, short, and should not extend past the fingertips. I realize that men are more comfortable with this concept than women, therefore women with longer nails should at least use a nail brush frequently when washing hands.