Soap nuts are demonstrated to be less of an irritant than mainstream detergents – even the “so called” Free and Clear products.
In vitro (test tube) ocular testing of soap nuts/saponin has recently (2009) been conducted via a US independent laboratory. A non-disclosure agreement limits me at this time from providing all the specifics regarding who conducted the tests, plus the patented processes that were utilized. No animal testing of any kind was involved.
The tests were conducted using cultured human cells from the cornea. The tests evaluated the level of irritation that exposure to soap nuts/saponin-based and mainstream commercial detergents would develop. It is significant to note that ocular testing is possibly the best measure of toxicity due to the sensitivity of the eye.
For the saponin detergent a variation of NaturOli’s Extreme 18X was used. It was reduced to a level of potency equivalent to that of the other detergents it was compared to. Given the high concentration of Extreme18X, adjustments needed to be made to have a true apples-to-apples comparison.
Note: Triton X-100 is not a commercial or retail “brand” detergent. It is a non-ionic surfactant commonly used for laboratory testing. It is used as a proper control sample for such testing.
See: http://en.wikipedia.org/wiki/Triton_X-100 for more information.
The study is quite complex, but the net of the net is the following comparative results:
NaturOli’s Soap Nut Liquid Laundry Soap – “minimally irritating”
Triton X-100 (the control sample) – “mildly irritating”
2X Ultra Tide HE Free Detergent – “moderately irritating”
Seventh Generation HE Natural Free and Clear Detergent – “mildly irritating”
Method Green 3X Concentrate Free and Clear – “severely to extremely irritating”
Very significant to this testing is that each of the detergents selected for comparative study are the detergents marketed as the “greener” and more natural of each brand.
There were no surprises to me in the results of this testing. I have intentionally put tiny amounts of saponin and other detergents in my eyes to personally experience the results first hand. These results are consistent with my experience. I’ve tried many others, too. Soap nuts liquid and saponin is very gentle relative to everything I’ve personally tested.
VERY IMPORTANT: Please do not even think of trying this yourself. It’s not fun – at all. It hurts, and you could cause yourself serious harm. Even “moderately” is an understatement in my opinion, and “extremely” doesn’t come close to doing it justice. Wow! OUCH!
It should be noted that NaturOli’s Soap Nut Liquid Detergent contains only vegetable glycerin, olive leaf extract and “food” grade preservative as additives to its saponin extract. NaturOli uses a proprietary aqueous extraction process (water based) that is also very safe and benign. As I’ve mentioned elsewhere, there are soap nut liquids that utilize very hazardous chemical extraction processes. Not all saponin extracts are alike. Hence, this test does not imply that all soap nut detergents will produce the same results.