Possible Reasons for Why We Differ in Our Perception of Scents

I thought this was an interesting post on another blog by scent scientist Avery Gilbert about research into why we perceive the same scent molecules differently: Is Fragrance Preference Written in Your DNA?

He begins by saying “How is it that the same odor molecule smells strong to one person and not at all to another? Or that some find an odor disagreeable while others judge it mildly pleasant? Extreme person-to-person variation is the hallmark of odor perception. It intrigues and frustrates sensory scientists—not to mention fragrance designers and chefs.”

I think about these issues when I work on new scents, so it was interesting to me to read his post on new research into differences in our olfactory receptors that can cause these differences in the way we smell things. The differences go beyond some people being anosmic to musks, and they go beyond preferences and personal experiences. As Gilbert says, people can “disagree about an odor’s basic olfactory character (e.g., is it like musk, urine, or sandalwood?).”

The person-to-person variation is fascinating and challenging all at the same time.

The Difference Between Ingredients, Ingredient Lists, and Notes

I’ve had a number of people ask me about the differences between what’s actually in the bottle (ingredients), what is listed on the box (ingredients list), and what is listed in the notes for a fragrance. I’ll give a brief explanation of how these things differ.

The notes given for a fragrance are a description of what the scent is supposed to smell like rather than an exact list of what is in it. The fragrance might have an oakmoss note, but you won’t know from the notes list if it has real oakmoss in it or not. The fragrance might list jasmine or rose, and you won’t know if these are partly synthetic and partly natural, all natural, or all synthetic. With the exception of all-natural perfumes, most floral accords these days are combinations of naturals and synthetics. Some companies let you know that the product includes natural ingredients by listing the phrase “essential oil” or “absolute” after the item, as in patchouli essential oil or jasmine sambac absolute.

A list of ingredients is required, but the USA and EU (European Union) requirements are different. In both cases most of the fragrance ingredients are kept secret by lumping them into the word “fragrance” or “parfum” in the ingredients list. The list also contains the non-fragrant ingredients, usually water (or aqua) and specially denatured alcohol such as SD39C. Some fragrances may list colorants or sunscreen additives.

In addition, the EU requires that certain fragrant ingredients be listed rather than lumped into the secret “fragrance” term. The EU created a list of 26 fragrance materials they deem to be potential allergens and these items must be disclosed in the ingredients list if they occur at a level higher than 10 ppm (parts per million) in a leave-on product like perfume. Oakmoss/treemoss is one such item, so if you see Evernia prunastri or Evernia furfuracea on the ingredients label you know the product has natural oakmoss or treemoss in it. Some perfume lovers who want natural oakmoss look for this listing on the label. Some synthetic ingredients must also be listed, like linalool and eugenol, but it’s worth noting that many of these ingredients are also found in natural essential oils and thus can be of natural or synthetic origin. Remember that even if this ingredients list looks long, it is not a full listing of what’s in the perfume formula because many more things are hidden in the “fragrance” or “parfum” term.

I’ve not made my labels conform yet to the EU listing requirements since I don’t sell in the EU, but it is something I’ll probably do later this year. I do indicate the prescence of natural oakmoss in scents by listing “oakmoss absolute” in the list of notes, and over the next few months I’ll be substituting the new natural low allergen moss into all my formulas.

I hope that’s the last post of this nature for a while (I’m guessing people want to hear about other things too, but you’re always welcome to write with suggestions or requests for post topics); I hope some of the info has been helpful.

Understanding the Nature of a Sensitizer

Many people want to have the informed choice whether to use products with natural oakmoss and other potential sensitizers, but to make an informed choice they need to understand the way a sensitizer works. You can use a product that contains oakmoss for years and then all of a sudden start reacting to it with itchy, red rashes. It takes cumulative exposure before your body becomes sensitized enough to start reacting, and you never know when that might start, if at all. I have not been sensitized to anything so I can’t offer personal experience (I’m very lucky not to have any skin, sinus, or headache issues with fragrance at all, at least so far).

I hear a lot of people say just to avoid products with oakmoss “if you are allergic to it” but this really isn’t accurate. By exposing yourself to moss over and over you can become sensitized to it and start having allergic reactions on your skin. One of the big questions is how many people will be sensitized and whether the numbers merit regulating the material. That question has to be answered by research and statistics, and the regulating bodies decided it is enough of a problem to set rules on oakmoss levels. Then the next big question is what level of the sensitizer is acceptable in the product, and I suspect researchers don’t really know how low to set it in many cases. However, now that we have a good treated natural oakmoss with low levels of the two main identified sensitizers, atranol and chloroatranol, it makes sense to switch to the new moss to prevent new people from becoming sensitized.

For people to make informed choices, they need the information. A significant portion of fragrance collectors don’t understand how a sensitizer works, and the general public is probably more in the dark. All this talk about the issue should at least help people understand more about what sensitization involves.

Edited to add: I think consumers can make their own choices as long as the information gets to them. I hate to see fragrance labels looking like drug labels, but we may need to use more extensive and informative product labeling in order to leave as many choices up to the consumer as is possible. In the case of oakmoss though, the new natural moss product with low allergen levels really seems to make sense.

Oakmoss and IFRA 43rd Amendment

The Now Smell This blog had a discussion yesterday about the 43rd amendment to IFRA and I made a couple comments that I thought could use further explanation. The 43rd amendment keeps the usage rate for oakmoss at 0.1%, but any oakmoss used must have atranol and chloroatranol levels of less than 100 ppm. The only natural moss I know of that currently meets this standard is the new moss I purchased in early January from Biolandes. I had sampled it last fall and found it to be very nice, especially as compared to the synthetic alternatives, as I have mentioned on this blog a few times.

The synthetic options I have tried for oakmoss don’t really smell very close to real moss; Evernyl/Veramoss is a nice, sweet, earthy, slightly powdery smell, but it lacks many of the qualities of real moss (it has much softer character to me and misses the green and darker qualities real moss has). Givaudan Oakmoss substitute is not one I like, though maybe some other perfumers might like it. Orcinyl 3 is a synthetic that is supposed to work well together with Evernyl, but I have not tried that one yet. My search stopped with the Biolandes moss because it is a natural moss with the atranol/chloroatranol removed and it smells very much like regular natural moss. I had been skeptical that I’d like it since I’ve not liked other low-allergen versions of naturals I’ve tried (bergamot and lavender), but the moss is very nice and is so much better than the synthetic alternatives I’ve tried.

As a perfumer, I need to decide if I’m going to follow the IFRA guidelines (and there’s no choice about it if I want product liability insurance), and if I choose to follow the rules I need to find an alternative to the oakmoss I’ve been using. Since I like this new low atranol oakmoss and it should be safer from a sensitization standpoint, I bought a kilo and will be working it into my formulas. I took Jour Ensoleille off my list for now because it will be the first scent to be reformulated with the new moss; the oakmoss note is more important to that scent than to my others, so I’m starting there with the hardest one.

The reason I expressed some concern on NST about the 100 ppm ruling possibly being changed is because I’ve read a research paper that was part of the input that went into the 43rd amendment decision process, and that document suggested 2 ppm. Apparently they compromised on 100 ppm for the final ruling, but seeing that 2 ppm worried me. (That paper was called the SCCP, or Scientific Committee on Consumer Products, Opinion on Oak Moss/ Tree Moss, sensitization only April 15, 2008). The Biolandes moss shows no atranol or chloroatranol at all at a detection level of 50 ppm, but they need to measure it with a better detection level to document how low it really is.

So, from my viewpoint I think I’ve found a solution that will let me continue to create moss notes in fragrances. I think there is hope on this oakmoss issue because of the new low atranol moss, perhaps in combination with low levels of things like Evernyl. There are still many other restrictions being introduced on other ingredients in the 43rd amendment and I hope we can find solutions as we move forward, but I will be very sad if this is the end to many old classics. I’d love to see some exceptions granted for old classic formulas even though that’d be tough to decide where to draw the line. This is indeed a major blow to perfumery, but I think it would be unfortunate to just give up. There are still a lot of beautiful fragrances that can be made, and perhaps it’s not too late to find a way to save at least some of the old classics. The industry does listen to its customers even though the regulating boards don’t seem to be listening yet. I’m no expert on IFRA or these regulating organizations, so these are just my thoughts from dealing with the rules as they come along.

Edited to add:

Ayala just posted about the oakmoss issue today on her Smellyblog and is also using and liking this new low atranol moss, so I’m really glad to hear that! She also addresses the issues I was wondering about for why the big oakmoss panic for 2010?

And PerfumeShrine addresses the larger topic today concerning this latest panic about the 43rd amendment.

Spring Blossoms and Weekend Update

The wisteria is in full bloom in our area, so I snapped this quick photo today to post for spring.  I don’t have any in my garden, unfortunately, but it sure smells good.   My sweet peas are about a foot tall though, so I’m hoping for some of their scented flowers in a few weeks.

Here’s another review of Tabac Aurea, and this one shows the variability from one person to the next as this reviewer gets quite a bit of leather from it whereas the previous reviewer did not: review on Nathan Branch blog.

I think this scent is one you really need to try for yourself.  If you like tobacco it’s worth trying, but it’s always good to sample first to see what the scent is like to your nose and on your skin.

A fun garden-related aside: the botanical artist whose jasmine vine decorates my boxes and packaging has just illustrated another book.  Her name is Bobbi Angell and her illustrations have appeared in seed catalogs, in the weekly New York Times gardening Q&A column, and in garden and botanical books.  This most recent book, called Our Life In Gardens,  was written by Joe Eck and Wayne Winterrowd (two authors gardeners will recognize).  I just got a copy from Amazon and want to squeeze in some time to read it this spring.

I hope those who went to sniffa in NY this weekend are having fun! Sounds wonderful.

Tabac Aurea Reviews (and a note on scent individuality)

There’s a lovely review of Tabac Aurea posted today on I Smell Therefore I Am and the blog is giving away some Tabac samples if you are interested in adding your name to the hat. I’ve had feedback from more people on Tabac now as more samples get out, and it brings up the topic of scent variations from one person to the next.

Most of the feedback on Tabac so far has been wonderful, with people enjoying it very much. It appeals to people who want a tabac that’s not overly smoky or masculine but is still woodsy. People say it is an unsmoked pipe tobacco scent, which is how I intended it to be (I’ve not liked the cigarette vibe I get from a few tabac scents I’ve tried).

One variation in how people perceive Tabac Aurea is the sweetness level. To me, it is a woodsy gourmand with a gentle sweetness (not nearly as sweet as something like the scent Collection, but sweeter to me than the dry and woodsy Bell’ Antonio). The sweetness in Tabac Aurea comes from several ingredients: the tabac itself, some tonka, a sweet musk, and some amber/vanilla.

Many testers have found the scent to have a mild sweetness about the same as I do, but a few people have found it quite dry and I’m guessing some of them might be anosmic to the sweet musk in it. I couldn’t resist using this musk because it goes so beautifully with the tabac. The musk has a warm golden feeling to it and it has some soft subtle fruity notes that complement the tabac very well. This musk adds a lot to the yummy golden almost honeyed drydown of Tabac Aurea. Those who don’t smell the musk will miss out on some of that, though the tabac itself is yummy and the various amber ingredients add to that golden feeling too.

Another perception that varies is the amount of leather people get from Tabac Aurea. It has both tobacco and leather notes, and to me the leather opens stronger and softens as it goes, but to me the scent has more tabac overall than leather. Most of my testers found that to be true as well, but some people do get more leather than others, presumably because they are more sensitive to leather notes and pick them up at lower levels. So the leather to tabac ratio in Tabac Aurea will depend on whether you are relatively more sensitive to leather or tobacco. Sensitivity is different from liking vs not liking; people can sometimes very much like a note they are sensitive to as long as it is kept soft enough so as not to overwhelm the other notes for them.

Here’s another way to look at this. If you were to take the main ingredients of the tabac accord and put them in one vial and put the main constituents of the leather accord in another vial and let people sniff the accords in isolation, they’d probably mostly describe them in similar ways. Then if you asked the same people to mix a blend of the two accords that seemed to smell like it was balanced 50/50 leather/tabac, I bet the percents they’d use of each accord would vary a lot.

I hope I’ve not totally bored you with this topic, but it’s worth remembering that people will vary in their perception of scents depending not only on their preferences but also on what ingredients they are sensitive to and what ingredients they are anosmic to. Keeping that in mind will help you understand when you smell something and find it different than someone else does. Neither one of you is nuts, lol. 🙂