# Ivory Soap's purity **URL:** \ **Category:** Factual Questions\ **Created:** [March 22, 2013, 2:21am UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602 "2013-03-22T02:21:33Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [March 22, 2013, 2:21am UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/1 "2013-03-22T02:21:33Z")
For decades, Ivory soap has always advertised that it’s “99.44% pure.” But I just bought some, and for the first time it has “aloe scent,” yet it still claims to be “99.44% pure.” Now, I don’t know how they add the scent, but shouldn’t it affect the purity somehow? Unless the scent itself is “99.44% pure,” it should make some difference, right? And by the way, what’s in that remaining 0.56%? ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [March 22, 2013, 2:42am UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/2 "2013-03-22T02:42:47Z")
[Cecil answered](http://www.straightdope.com/columns/read/424/if-ivory-soap-is-99-and-44-100-pure-whats-the-other-56-100) your second question twenty years ago. ---
**Author:** ![Learjeff](https://avatars.discourse-cdn.com/v4/letter/l/94ad74/32.png) [@Learjeff](https://boards.straightdope.com/u/Learjeff)\ **Post date:** [March 22, 2013, 4:12pm UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/3 "2013-03-22T16:12:12Z")
Cecil answered the other question too, by mentioning the important issue is “pure what?” If the scent is added on purpose, it’s not an impurity, by definition. Impurities are things we don’t want or didn’t intend to be in there. ---
**Author:** ![Si\_Amigo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/si_amigo/32/2877_2.png) [@Si\_Amigo](https://boards.straightdope.com/u/Si_Amigo)\ **Post date:** [March 22, 2013, 5:03pm UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/4 "2013-03-22T17:03:32Z")
nm ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [March 22, 2013, 5:07pm UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/5 "2013-03-22T17:07:41Z")
“You’re soaking in it.” ---
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [March 22, 2013, 5:10pm UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/6 "2013-03-22T17:10:59Z")
> [@Learjeff](#): > > If the scent is added on purpose, it’s not an impurity, by definition. Impurities are things we don’t want or didn’t intend to be in there. Unless they’ve updated the definition of “pure” soap, they still have to cram scents into that .56% …which is probably not that hard. The human nose can easily detect scents in the parts per million (actually, that’s the “this reeks of …” level), and industrial scents are very highly concentrated. According to this article ([http://www.extension.iastate.edu/Publications/PM1963C.pdf](http://www.extension.iastate.edu/Publications/PM1963C.pdf)) > [@](#): > > “Although the detection threshold concentrations of substances that evoke a smell are low, often times in the parts per billion (ppb) or parts per trillion (ppt) range, a concentration only 10 to 50 times above the detection threshold value often is the maximum intensity that can be detected by humans.” ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [March 22, 2013, 6:11pm UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/7 "2013-03-22T18:11:49Z")
> [@dstarfire](#): > > Unless they’ve updated the definition of “pure” soap, they still have to cram scents into that .56% …which is probably not that hard. I heard a really interesting take on the concept of additives (the actual discussion was about base oils vs. additives in motor oil) when someone pointed out that the main differences between Coca-Cola, iced tea, orange juice and hot chocolate were a few percentage points of additives to water. I’d wager that most soaps on the market are probably in the 95-99% pure soap range as well, and that 99 44/100 pure is probably a marketing tool more than anything else. ---
**Author:** ![typoink](https://avatars.discourse-cdn.com/v4/letter/t/ecb155/32.png) [@typoink](https://boards.straightdope.com/u/typoink)\ **Post date:** [March 24, 2013, 2:57am UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/8 "2013-03-24T02:57:57Z")
For the record, I should point out that Aloe-scented Ivory is an abomination. It still pretty much just smells like Ivory soap, only with a tiny hint of weird. If you’re going to have exactly _two_ varitions of your product on the market, would it kill you to make them more than just barely distinct? ---
**Author:** ![usedtobe](https://avatars.discourse-cdn.com/v4/letter/u/ec9cab/32.png) [@usedtobe](https://boards.straightdope.com/u/usedtobe)\ **Post date:** [March 24, 2013, 3:25am UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/9 "2013-03-24T03:25:48Z")
Do they still use the “So pure it Floats!” line? I suspect the reason it floats has nothing to do with the soap - it is just how much air is trapped in it during mixing/whipping. Hell, if I form a really thin-walled ball of lead, it’s float - pure or not. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [March 24, 2013, 5:12am UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/10 "2013-03-24T05:12:35Z")
> [@usedtobe](#): > > Do they still use the “So pure it Floats!” line? > > I suspect the reason it floats has nothing to do with the soap - it is just how much air is trapped in it during mixing/whipping. > > Hell, if I form a really thin-walled ball of lead, it’s float - pure or not. Air isn’t soap and has no cleansing capability, so I’d classify air as an impurity. Which means their motto is the opposite of true - the reason Ivory floats is because it’s so impure. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [March 24, 2013, 6:51am UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/11 "2013-03-24T06:51:16Z")
> [@typoink](#): > > For the record, I should point out that Aloe-scented Ivory is an abomination. It still pretty much just smells like Ivory soap, only with a tiny hint of weird. > > If you’re going to have exactly _two_ varitions of your product on the market, would it kill you to make them more than just barely distinct? I actually like the aloe scent, even though I bought it accidentally. It masks the generic scent of Ivory. ---
**Author:** ![typoink](https://avatars.discourse-cdn.com/v4/letter/t/ecb155/32.png) [@typoink](https://boards.straightdope.com/u/typoink)\ **Post date:** [March 24, 2013, 7:23am UTC](https://boards.straightdope.com/t/ivory-soaps-purity/653602/12 "2013-03-24T07:23:07Z")
> [@panache45](#): > > I actually like the aloe scent, even though I bought it accidentally. It masks the generic scent of Ivory. Remind me to never bathe with you. Err. Something like that.