Recently, a fragrance blogger who is given to disliking Terre d'Hermès made an embarrassing error regarding the usage of Iso E Super in the fragrance. He wrote the following on Fragrantica:
"From the Wikipedia iso e super page: 'The very popular Terre D'Hermes (Hermes, 2006) contains 55% Iso E Super (of the perfume compound).' But now: 'IFRA restricted to 21.4% in concentrate for perfume use.' That is from the evocativeperfumes site. When they use percentages it always means the fragrance portion, and does not include the perfumer's alcohol content, from what I understand . . . in any case, from what I've read about safety testing on iso e super I would not use the original TdH even if I preferred it to the latest formulation!"
Reading this would lead one to believe that the EDT now contains up to 21.4% Iso E Super, where once it was 55%. However, he misunderstands what he wrote. He cited percentages in two categories: "Of Compound" and "In Concentrate." There is an obvious difference between them, which was pointed out by another member, who calls himself "blonc":
"In order to help avoid confusion, I'm going to correct the review below by Bigsly, who doesn't understand the numbers he was discussing. From the Wikipedia iso e super page: 'The very popular Terre D'Hermes (Hermes, 2006) contains 55% Iso E Super (of the perfume compound).'It's important to understand the phrase in parenthesis above: Of The Perfume Compound. That refers to the combination of ingredients before being diluted in alcohol to bring the final product down to eau de toilette strength (an EdT is usually 12% to 15% perfume compound and 85% to 87% alcohol).But now: 'IFRA restricted to 21.4% in concentrate for perfume use.' That 21.4% represents the final perfume including the alcohol. In other words, the formula Terre d'Hermes is 55% Iso E Super, but that's before being diluted. The final product, after being diluted down to EdT strength, is more like 7% Iso E Super, which is far below the 21.4% allowed by IFRA (55% of the formula, diluted down to 13.5% strength). Hopefully that helps clear up any confusion. I mean, come on now, if TdH was 55% Iso E Super after being diluted in alcohol... holy moly, it would be at least twice as strong as the strongest EdP. It'd be an attar! And it would be unwearable."
There was never any doubt that the formula (at least at one time) contained 55% Iso E Super. Whether it still does is up for debate, but I never thought the EDT (or EDP) contained that much! "Of Compound" refers to the aroma chemicals combined in a formula before the addition of alcohol. "In Concentrate" refers to the concentration of the fragrance in alcohol as the final product: EDC, EDT, EDP, etc. Division by dilution is necessary. When you consider that the average EDT is roughly 87% alcohol to 13% formula, and you further consider what percentage of the formula contains one specific aroma chemical, the result is likely around 5% for Iso E in TdH. Put another way, with TdH EDT, almost 100% of what you smell is not Iso E Super.
When you consider that aftershaves are 96% - 99% alcohol, you realize just how little of the fragrance formula is available. I suspect there's a drop of Iso E Super in Clubman Classic Vanilla, along with roughly one hundred other conventional aroma chemicals, but I would be lucky to detect less than 1% of any chemical, its fragrance is so vague and, compared to most EDTs, relatively cheap (and Classic Vanilla's formula by no means smells cheap). Unfortunately, the percentage of alcohol in most alcohol-based aftershaves is so high that the alcohol itself becomes a note. With the average EDT, the concentration of the formula is meant to be just high enough to mask the alcohol, and sometimes it doesn't even do that adequately.
This is interesting when considering how people complain about being overwhelmed by Iso E Super. They pretend to smell huge amounts of it in fragrances like TdH, when in reality they're not smelling it at all. They're "Feelers," not "Tasters." They "feel" that something is true, even though it isn't. Instead of actually using their noses to gradually analyze, they chronically sample and make snap judgments. The result is chronic disinformation about fragrance materials and their effects.
I wish I could use magic to dispel the disinformation campaign waged against Iso E and other materials, like Ambroxan, but alas, I left my wand in my other pants. I guess the old reality-based mainstays of logic and simple math will have to do instead.
Update 1/23/18:
The blogger in question has published a rebuttal to my post in which he states the following:
"I certainly wouldn't be the one to applaud more restrictions on Iso E Super (because I seem to be one of the people who have become hypersensitized to it), but unfortunately that doesn't seem to be an issue with IFRA at the moment . . . I still don't understand why it's necessary to talk in terms of 'in concentrate' and 'in compound' when we know the alcohol content is going to be so high, and we also know that of course it's been diluted into the alcohol, or else it would smell differently when we sprayed it!"
His article basically admits that I'm right, and I'll answer his question here: we need to talk in these terms because they're distinctions. Without these distinctions the percentages lack specificity, and therefore lack meaning. If someone says 55% of Iso E is in a fragrance, I need them to clarify whether he is referring to the formula prior to dilution in alcohol, or if he is referring to an attar from Saudi Arabia. Generally the percentages aren't that high, so it's more likely I'd hear something like, "There's 8% Iso E Super in this frag." Again, is that the formula, or is that the final fragrance, where there's probably something like .8% ies?
Another humorous issue with this person's blog post is this snippet:
"As to claims that some people are imagining ies content, we only have to turn to the Wikipedia page on this aroma chemical to see the reality there."
Unfortunately the Wikipedia page misleads the blogger into thinking that Iso E Super causes olfactory hypersensitivity, when in fact it only says that it causes topical hypersensitivity, otherwise known as a "rash," and this is only proven via animal testing on mice. Thus far there is little to no information regarding olfactory sensitivity on the Wikipedia page, which only says:
"Iso E Super may cause allergic reactions detectable by patch tests in humans, and chronic exposure to Iso E Super from perfumes may result in permanent hypersensitivity."
"Hypersensitivity" has its own Wikipedia page, which states that these are a set of undesirable reactions produced by the normal immune system, "including allergies and autoimmunity." Since "patch tests" are skin tests, and because "hypersensitivity" is another word for "allergies," one can only conclude that the blogger has either misunderstood the material he has cited, or hopes that his readers will. I can say that any suggestion that miniscule amounts of Iso E Super in commercial fragrances will cause strong negative reactions to one's sense of smell are unsupported by my friend's "patch test" argument.