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Wow! Those Volatile Organic Compounds Smell Great!

by Eric Hall

February 23, 2014

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Donate I came across a post on Facebook which is actually pretty dangerous. Not in the normal way I tackle on this blog of people buying useless products or increasing the risk of disease long-term by not getting proper medical treatment, but in a more immediate "please don't do this ever" sense. The accompanying photo is to the left - as linked from the post on the site Pinterest. The suggestion is to put "1 [tbsp] Vicks Vapor Rub & 2 [tbsp] water in your Scentsy." Note: Don't do this!!This led me down the scent/candle/essential oil rabbit hole and I will share a little about the dangers of these practices.

First - don't put these two things in anything that heats up. These Scentsy warmers are designed to melt scented wax products sold by the Scentsy company. The danger of putting vapor rub in with water and heating it is it can cause splattering (and thus a burn), could potentially start on fire as it evaporates, and is directly against the label directions on the vapor rub. So just don't do it.

Does Vapor Rub Work?

This is an interesting topic. There is the common belief it does work in a couple ways. One that often goes around is to put vapor rub on a child's feet and put socks on when they go to bed to relieve cold symptoms. There is very little plausibility that this does anything, and could be slightly harmful for younger children in that it could irritate their skin. It is just silly.

The more traditional use is to rub it on a child's (or adult's) chest for relief of cold symptoms. There isn't much in the way of study here either, though one study did come up. The study seemed to convince Dr. Swanson at Seattle Children's Hospital, but I am not as convinced - though she does provide a reasonable hypothesis as to why the results were as they were. As Dr. Swanson reported on the study design:
  • 138 children between 2 and 11 years old enrolled in a 2 day study while they suffered from cold symptoms. These kids did not have asthma or other lung issues and weren’t using any other medications or interventions, not even honey.

  • Parents were randomly placed in 4 different groups: one group that used no treatment and 3 treatment groups that used either placebo ointment, petrolatum (think Vaseline) on a child’s chest, or Vicks VaporRub (petrolatum with camphor [4.8%], menthol [2.6%],and eucalyptus oil) on the chest. To ensure families in ointment groups didn’t know which ointment they were rubbing on the child’s chest, they had parents put a strip of the vapor rub under their own nostrils so they couldn’t smell if the ointment they applied was medicated or not. Hmmmmmmm…would you be able to comply with this? Would you sneak a sniff at another time?

  • Children (and parents) were assessed for cough, congestion, and difficulty sleeping (one of the biggest consequences of colds).

The study size was small, and I don't see this as being well controlled. The parents put a strip under their nose while applying the ointment, but I know I can still smell the vapor rub in the morning when I've used it. I don't think this is an easy thing to control. To go with that, because the assessment was largely what parents reported, better controls would be important. I just don't see this as definitive. What were the findings?:
  • Most significant were results rated by parents: children treated with Vapor Rub were significantly more able to sleep than were children randomized to receive petrolatum or no treatment.

  • Researchers wrote, “Combinations of aromatic oils in a petrolatum base have been used for generations, but this study demonstrates that this therapy is indeed effective.”

  • As rated by their parents, children with URIs who were treated with Vapor Rub had more nighttime relief from cough, congestion, and sleep difficulty than did children treated with a placebo ointment, petrolatum, or with no treatment.

  • It’s unclear why Vapor Rub helps children sleep. The researchers theorize that it is due to relief of other symptoms (cough/congestion).

  • Twenty of the 44 parents in the Vapor Rub group reported one or more mild adverse event, such as skin irritation. No parents in the other two ointment groups reported side effects.

The "ancient medicine" gambit in reporting the results makes me further question the results. An argument from antiquity should not be a reason something works. The only argument for mentioning the many decades of use is in assessing the relative safety (it shouldn't be the only thing, but it does help).

Dr. Swanson does make a good point in mentioning that one possibility is the kids with the vapor rub sleep better because the camphor and menthol helped the children feel the air in their nasal passages as they breathed. I can say anecdotally, as a kid I enjoyed putting on vapor rub when I had a cold. It might have been a placebo effect. Though Dr. Swanson concluded she wasn't convinced it was helpful, she also didn't see much harm in it for children over 2, especially if it helps them sleep. I would agree with her conclusion.

It's Chemical Free (apparently)

The other part of the Pinterest post was this statement:
...easy breathing with no chemicals in or on your body. Best info yet!!
I'm not sure how this is expected to do anything without getting any chemicals in or on your body, but any basic knowledge of science should tell you this is wrong.

One Scentsy consultant has her own blog on the subject. She of course had an interest in deterring people from the practice of putting vapor rub in the warmers. For one, it voids the warranty. The other is the "dangerous ingredients" which should not be inhaled - but sure enough she has an alternative product to use instead! She points out the dangers of some of the ingredients - and she is correct in a sense that in large enough doses, they can be dangerous (camphor and turpentine for example). It is also reasonable to say the concern of side-effects is increased when warmed because it is increasing the rate of evaporation. Probably good reason to avoid the vapor rub warming - and certainly not "chemical-free." As a side note - how does one live being "chemical-free?" Isn't that a bit like being "existence-free?"

What's in the wax?

Some websites are very critical of Scentsy. As one website points out, Scentsy admits their ingredient list is a secret. They have good motivation to do so, as they don't want people copying their product, and scents are very difficult to patent unless the applicant can show it is a new molecule.

The website also points out the wax in Scentsy products is made from petroleum. They then make the false equivalency that this somehow means they contribute to pollution by referring to the Deepwater Horizon spill in the Gulf of Mexico. Petroleum wax is a by-product of refining oil into other products. I personally find using these by-products to be better than simply disposing of them from an energy standpoint. In the case of Scentsy, the wax isn't even burned, so any concerns about combustion products is nullified. I don't find any valid argument in pointing this out.

Another website called "Organic Slant"is more critical of Scentsy. They make several claims about the "dangers" of Scentsy and then go on to tout how essential oils are so much better (but only the brand they sell of course). They do point out one legitimate misrepresentation by Scentsy. Scentsy's claim:
"Scentsy Warmers only warm the scent out of the wax - the wax remains in the warmer, thus there is no danger of chemicals being released into the home."
Organic Slant responds:
No danger of chemicals being released? Really? Fragrance oils are made from chemicals created in a lab. The fragrance oil is completely released until the wax is unscented. Obviously, it doesn't take a rocket scientist to figure out that you are inhaling chemicals from the fragrance and CHEMICALS ARE BEING RELEASED INTO YOUR HOME AND BODY.
Very true. If no chemical was released, there would be no scent. So even though the site makes it sound like any chemical in your home is dangerous (which is also very disingenuous), we really need to be more precise with our scientific terms like chemicals and stop using buzz words like "chemical-free" which would truly mean "nothing."

The site goes on to describe the "dangers" of volatile organic compounds (VOCs):
The toxic chemicals released by air fresheners "particularly those with pine, orange and lemon scents " are known as volatile organic compounds (VOCs). These are well-proven toxins, many of which have been linked to a range of diseases and conditions when being inhaled even in low concentrations over a long period of time.

Some of these chemicals includebenzene, petroleum-derived chemical, which causes cancer in animals and has been linked to leukemia;xylene, which has been linked to nausea and sick building syndrome, as well as liver and kidney damage;phenol, which can cause kidney, respiratory, neurological and skin problems;naphthalene, a suspected carcinogen, which has been linked to blood, kidney and liver problems; andformaldehyde, a colorless, unstable gas. Inhaling formaldehyde fumes in even small amounts can cause coughing, a sore throat, and respiratory and eye problems. Formaldehyde has been linked to cancer, particularly in the nasal cavity.
Ok - so here's where this website starts to misunderstand the science. A VOC is basically any chemical with carbon in it (making it organic) and having a high vapor pressure at room temperature. In other words, a VOC easily turns into vapor and disperses in a room. This is how almost all smells work, not just the ones in Scentsy (as pointed out in this blog defending Scentsy for example). So the essential oils Organic Slant touts as a safe alternative - also contains VOCs. While the VOCs listed above can be dangerous if in high enough concentrations, any VOC, including essential oils, can cause irritation and health problems if the concentration is high enough.

I'll give an example. One of the oils touted by many essential oil defenders is oil of thyme, which one of the main components is thymol. It is one of the antiseptic ingredients in Listerine mouthwash. It is also a component of "organic" and "natural" insect sprays and cleaners (which I do use in my home because I like the smell). But just because it is labeled as "natural" or because it "comes from plant sources" doesn't make it free of danger. Let's look at a couple of notes from the MSDS:
Personal precautions
Use personal protective equipment. Avoid dust formation. Avoid breathing vapours, mist or gas. Ensure adequate
ventilation. Evacuate personnel to safe areas. Avoid breathing dust.

Environmental precautions
Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment
must be avoided.
In fact - even the handling instructions are to avoid formation of vapors - which is precisely what essential oil proponents are telling you to do. Precautions include wearing an N100-type mask when handling the stuff. This is because what makes it have a scent, and what makes it vaporize easily is because it contains VOCs. But remember - it is 100% natural and safe if I believe the essential oil people.

Another consideration the "natural" and "oil" crowd don't consider is the uptake of heavy metals in plants and thus ending up in the oil. In fact, much research has been done on using plants as a way to clean up heavy metal contamination in heavily contaminated soils in a process calledphytoremediation. I looked at several different oil sites - and while all claim their purity is the best - they don't say anything about testing for these type of contaminates in the oils - only that they have the best process for extracting the oil. It should be noted these oils are complex mixtures of chemicals, and thus the processes they describe sound a bit dubious as to guaranteeing purity. It is possible that as you are breathing in the vapor, you are also breathing in heavy metals.

It should be obvious I am being a bit inflammatory in my statements. I don't necessarily think that having a little bit of plant oil diffused into the air in your home is harmful (because the amount is very small). In fact, the nice smell might provide enjoyment to many. However, the claims that these vapors are the magic cure for everything is wrong. To also claim that it is 100% safe - even when ingested (as some do - see the comments on an earlier blog on essential oils) - is also wrong. Like any product, it can be dangerous at a high enough dose. With some of these oils, the dose is not all that high. With others, there isn't good data on what is safe for vaporizing or ingesting. I advise caution on using these as air fresheners, and even more caution before you start swallowing these products.

Organic Slant has other options they claim are better:
1) NON-GMO soy tart or candle is one option. (only non-GMO or else it's just as bad as breathing in paraffin)

2) Beeswax. It has a natural light honey aroma, burns clean, and can actually HELP your health! Beeswax emits negative ions into the air and can help rid your home of toxins.

3) Young Living essential oils in the wide variety of cold air diffusers available. You have hundreds of essential oils to choose from ALL which produce positive therapeutic benefits!! One example: the Thieves blend, an exotic cinnamon clove scent that has been shown in research studies to kill 99.96% of airborne bacteria. Another study showed diffusing Lavender reduced blood cortisol levels (stress hormone) by 20%.
Number 1 shows a complete misunderstanding of combustion. Number 2 is almost comical - much like the long argument I had with the grounding/earthing proponents - these ion claims are simply preposterous. Number 3 is also much like the earthing proponents claim - the cortisol claim. Cortisol is a stress hormone, which often comes up with woo treatments as the treatment reducing stress. Yet in every case I have read to this point, there isn't good controls for the simple relaxation component of the treatment. If I sit in a chair and relax, my stress is likely to go down - whether I am breathing lavender, cinnamon rolls, coffee, or even listening to quiet classical music. It isn't the oil doing the job, it is the relaxation.

What should we conclude?

Don't take advice from social media when it comes to anything health related. In fact, don't even take my word for it. Talk to a doctor about your health. Maybe even talk to two. Look at the science. Look at the plausibility.Follow the directions on the label off the products.

Vapor rub is likely a placebo effect if used as the label directs, but if used in that manner is mostly harmless.

Do feel free to use Scentsy products, diffuse oils, or any other scented commercial product if you like the smell, but don't expect anything magical to happen.

Don't believe any claims if they include "all-natural," "chemical-free," or include other buzz words or distracting scare-tactics that obviously don't understand the science.

So don't put vapor rub in your Scentsy warmer. It doesn't do anything and is potentially dangerous.

by Eric Hall

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