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HELP ????
Posted by Chela on September 25, 2023 at 8:48 pmHi there! I need some help with some preservatives I’m using. Wondering if it’s enough to use as a broad spectrum system. Working with a 4.5-5.5 PH in a hydrous solution for a scalp/hair treatment (about 10oz/300ML). Using Phytocide Aspen Bark Powder at 2.5%, Potassium Sorbate and Sodium Benzoate. Will this be enough to provide full preservation? Wondering if to add Benzyl Alcohol for that extra push. However, I wouldn’t want it to be too drying on the hair shaft.
Also using Cetearyl Alcohol as an emollient to break down/mix in my added oils.
Would love some good and positive feedback! Thanks in advance.
PhilGeis replied 10 months, 4 weeks ago 4 Members · 13 Replies -
13 Replies
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Good grief - drop the silly PhytoBS. No one knows what’s in the stuff - other than the claim of “salicylates”. Assume you are chasing “clean” BS, control your pH to <5, drop the sorbate, do add benzyl and perhaps a long chain glycol. You need a chelator like EDTA. Find your own green one but not gluconolactone.
Your problem is Gram negative bacteria.
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Hi Phil! Thank you for your response. Very helpful information. I thought about dropping the Phytocide, I used it primarily because it made my hair feel extra silky and because it helped heaps with lowering the PH in my formulation. I might go with Citric Acid as a mild chelator instead and to help reduce the PH instead of the Phytocide (after mixing the preservative in). May I ask why you suggested to drop the Potassium Sorbate? I have a preservative that has a mixture of Benzyl Alcohol, Potassium Sorbate, and Sodium Benzoate all in one… with Benzyl Alcohol ranging as the highest. Would using that mixture used at 1.5%, plus Citric Acid and the Cetearyl Alcohol be effective? So far no bacteria, mold or yeast seem to be present after a week of testing (without the citric acid added yet). Thanks in advance.
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Prob doesn’t hurt to add sorbate - the stuff isn’t that stable through time consistent with consumer use.
Citrate is not that good a chelator in this context (but prob as poor a prevative as phytoBS). Maybe GLDA?
“seem to be present” - is this in challenge testing or just de facto content testing?
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I’m currently testing this myself trying to figure out what works best for the formulation to be effective not just in preservation but effectiveness with what I’m trying to achieve with this product to give actual results. I have been performing tests to identify contaminants and no visible bacteria, yeast or mold has been present after a week of diy testing. This is all prior to sending it for a USP61 and Challenge test.
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Even if not looking to be distributed internationally yet?
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Yes - the bugs are the same anywhere and USP is way way to easy to pass. Use ISO 11930 A crtieria.
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Dr Phil….has even written a book on the topic…. if you have interest. 🙂
Aloha
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Thank you for the support in tagging Phil!
I will definitely check it out. Aloha!
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Does passing the ISO 11930 criteria A mean the product is also recognized as safe in US markets? In other words, does passing ISO 11930 criteria A make USP<51> unnecessary?
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These are effectively the same test in execution with 51 crtieria being less stringent. As established passing through stability, it would be seen as justifying marketing.
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