April 04, 2012
by Robert Tisserand
I am not against transparency in labeling. I think it’s a subject that could use a lot of discussion. But I am against ingredient obsession. In a society that allows alcohol, tobacco and firearms to be freely purchased, and that turns a blind eye to the widespread use of illegal drugs, why are we concerned about whether a consumer product might contain a few parts per million of chemical X? Should we not be concerned, rather about whether the product itself is safe?
Ingredient tunnel vision is seriously bad for your health. It will turn you into an obsessive, paranoid, vicious, spitting fireball of righteous indignation. You will write searing blog posts, develop gastritis or worse, lose sleep, and die young. And for what? Essential oils and their constituent chemicals are very frequent targets. Because essential oils contain chemicals, and because almost all chemicals are, to some people, toxic by definition, many bloggers in the green movement have become anti-fragrance and anti-essential oils. For a while I though that, when they realize that linalool is found in lavender oil, and that limonene is in lemon oil, they will relent. I was wrong. Obsession is, in fact, relent-less. It allows no release, no vacation, no light side. It is all-consuming!
Because essential oils are alleged to contain “allergens”, they are also favorite targets of regulators and legislators, especially in Europe. And, we in North America know full well that whatever happens in Europe must be good, because Europeans are more intelligent. Their accents prove this. Since I have been living in the US (12 years now) my accent has slowly become less English English, and more American English, and my mental faculitoes have detturiated protortionisely, as you kan see.
More on Europe soon. But first, a new study financed by Silent Spring Institute, written by Robin Dodson et al, and published in Environmental Health Perspectives. EHP claims to be peer-reviewed, but if this report is anything to go by, its reviewers need replacing. In fact, they might as well not bother with peering, since it clearly accomplished nothing. The report is entitled: Endocrine Disruptors and Asthma-Associated Chemicals in Consumer Products. Classes of chemicals that were tested for include UV filters, cyclosiloxanes, glycol ethers, parabens, phthalates, alkylphenols and fragrances. The “fragrances” tested for include these essential oil constituents:
For your edification, I have highlighted one essential oil and also some foods that naturally contain said chemical. No rationale is given for why these particular substances were selected. This is important, not only because they have now become what might be called “target chemicals of concern”, but because the list could have been so much longer. It could include almost every essential oil constituent in existence. Now, at a rough guess, this is in the region of 1,000. The above list is said to represent “asthma-related chemicals”. This is not defined anywhere, but the article begins with “Laboratory and human studies raise concerns about endocrine disruption and asthma from exposure to chemicals in consumer products” and it goes on to talk about “asthma-related chemicals.”
Fragrance chemicals do not cause asthma, but they can exacerbate asthmatic symptoms. Many fragrance chemicals have this potential because they are very mild respiratory irritants in concentration. It’s the nature of the beast. However, listing limonene, isobornyl acetate, terpineol etc., is not helpful. If you are asthmatic, and you tend to react badly to fragrances, then you stay away from fragrances. Mounting a new campaign to list particular fragrance ingredients on consumer labels will not accomplish anything. It will not meaningfully make fragrances safer, and if consumers need a warning that a product is fragranced, this can be accomplished in either one word: “FRAGRANCE”. Or two: “CONTAINS FRAGRANCE”.
The paper states that, if a compound is “available from plant materials”, it was described as natural, and if “commonly synthesized”, then it was described as synthetic. But there is no list! No classification! So we don’t know which they regard as natural, and which as synthetic! In the text, limonene is mentioned as being natural (correct), isobornyl acetate as synthetic (incorrect) and hexyl cinnamaldehyde as natural (incorrect, since it is always synthesized. It is also spelled wrongly throughout the article. I’m Just saying…).
No direct evidence is provided for any adverse health effects for any of these compounds, and there is no discussion of the factors involved, although several papers are cited: “Fragrances, particularly terpenes such as limonene, are associated with secondary chemical reactions in indoor air, and can contribute to the production of formaldehyde, glycol ethers, ultrafine particles, and secondary organic aerosols (Nazaroff and Weschler 2004; Singer et al. 2006). Exposure to fragrances has been associated with a range of health effects, including allergic contact dermatitis, asthma and asthmatic exacerbations, headaches, and mucosal symptoms (Heydorn et al. 2003; Kumar et al. 1995; Steinemann 2009).”
Dodson and friends do not mention that moderate-to-high levels of ozone are required for these reactions to take place, nor that cleaning products (which can also contain volatiles such as formaldehyde, benzene, toluene and xylene) are the only ones that have been reported to cause actual health problems (Nazaroff and Weschler 2004). Ozone-limonene reactions can produce hydroxyl radicals, and these in turn can contribute to formaldehyde formation (Fan et al 2003). However, this was only observed under conditions that were admitted to be not typical of “nonindustrial indoor environments.” And, the statement that terpenes such as limonene can contribute to the formation of glycol ethers is not true. Nazaroff and Weschler (2004) state that both terpenes and glycol ethers were found in some cleaning products, not that one is formed from the other! And while I’m on my soapbox,, ultrafine particles and secondary organic aerosols are the same thing. Now, if I can find this many holes in a research paper without breaking a sweat, where is the so-called “peer-review”? And how much credence can we give any of the findings?
The Kumar et al (1995) study did find exacerbation of respiratory symptoms in asthma patients when they smelled perfume scent strips, as used in magazine advertising. And other research shows that if you give asthma patients strong fragrances to inhale, they may react adversely. The same is true for people with multiple chemical sensitivity, but it is not true of the general population.
Under extreme conditions terpenes such as limonene and pinene do form particles that are respiratory irritants. These conditions require (a) moderate-to-high ozone, and (b) substantial quantities of vaporized terpenes. These may be hazardous for vulnerable individuals, such as babies, older people, or people with asthma. However, it’s a leap to assume that fragrances cause health problems. They don’t. Yes, a fragrance could trigger an asthma attack in a person with asthma. But it cannot cause asthma. In a mostly supportive Forbes blog post based on Dodson’s article, Amy Westervelt quotes the following lines:
“This study presents a clear example of biased, advocacy-based research,” says William Troy, Ph.D., Scientific Advisor the International Fragrance Association North America. “It is a repackaging of older information and the methodology used defies basic principles and standards of scientific protocols and investigations. The advice to consumers based on study findings is simply wrong,” said Dr. Troy.
“There’s been a lot of work done on exposure to these chemicals in average households, and we know that these chemicals are found in air and dust in peoples’ homes, and the CDC [Center for Disease Control] has shown that we find them in our bodies as well,” says the study’s lead author Dr. Robin Dodson. “Now we’re trying to understand where the chemicals are coming from, and how people are exposed to them.”
There is a degree of naivete in this last statement. As far as the fragrant compounds are concerned, they are naturally found in some common foods (see Table), so that could be one reason that they are found in our bodies. Limonene and pinene are ubiquitous simply because so many trees produce them. If you have pine furniture, it is giving off limonene and pinene vapors. If you have paint thinned with turpentine, same deal, because turpentine is made from pine trees. If you live near trees…basically, if you’re breathing, you are inhaling limonene and pinene. How much you are inhaling, what the ambient ozone level is, and whether or not you have asthma are all considerations in whether these vapors might present a hazard. Some advice:
- If you are asthmatic, beware of strong fragrances.
- In high-ozone conditions (usually hot weather combined with factory exhalations and/or much vehicular traffic) beware of exposure to high levels of fragrant molecules.
- When using cleaning products, paints, glues or varnishes, ventilation is important.
- Note that some types of office equipment, such as photocopiers and fax machines, give off ozone.
Dodson advises avoiding fragranced products, and looking for ones with plant-based ingredients. So would that include or exclude essential oils? I’m baffled.
Dodson R, Nishioka M, Standley LJ et al 2012 Endocrine Disruptors and Asthma-Associated Chemicals in Consumer Products.
Fan Z, Lioy P, Weschler C et al 2003 Ozone-initiated reactions with mixtures of volatile organic compounds under simulated indoor conditions. Environmental Science & Technology 37:1811-1821
Heydorn S, Johansen JD, Andersen KE et al. 2003 Fragrance allergy in patients with hand eczema – a clinical study. Contact Dermatitis 48:317-323
Kumar P, Caradonna-Graham VM, Gupta S et al 1995 Inhalation challenge effects of perfume scent strips in patients with asthma. Annals of Allergy Asthma & Immunology 75:429-433
Nazaroff WW, Weschler CJ 2004 Cleaning products and air fresheners: exposure to primary and secondary air pollutants. Atmospheric Environment 38:2841-2865
Steinemann AC 2009 Fragranced consumer products and undisclosed ingredients. Environmental Impact Assessment Review 29:32-38
Robert Tisserand is internationally recognized for his pioneering work in many aspects of aromatherapy since 1969 and frequent contributor to the aromaconnection blog.