Home Cosmetic Science Talk Formulating Advanced Questions Pentylene Glycol and Preservative 12 Compatability

  • Pentylene Glycol and Preservative 12 Compatability

    Posted by OliviaLeigh on June 6, 2024 at 8:38 am

    Hi everyone - Its been a long time 🙂

    I have a question regarding a hydrating gel Im formulating which includes 5% pentylene Glycol for its moisturising and penetration enhancer ability but I know it can act as a preservative also. My question is can I or should I lower the preservative 12 in my formulation?

    92% water phase (pentylene glycol added here)

    5% oil phase

    2% cold process emulsifier

    1% preservative 12

    PhilGeis replied 2 weeks ago 4 Members · 19 Replies
  • 19 Replies
  • Microformulation

    Member
    June 6, 2024 at 10:31 am

    Is it leave on or rinse off? Also, with Preservative 12 (Phenoxyethanol/Ethylhexylglycerin, a dupe for PE9010) you need a chelant as well.

    In the end, any answers are theoretical. You could use the recommended level for Leave-on but in the end, testing is key.

  • OliviaLeigh

    Member
    June 9, 2024 at 12:56 pm

    Hi! Sorry for late reply 🙂

    Thank you. Its a leave on serum. I hadnt realised Preservative 12 needed a chelator! The whole formulation is made with natural plant oils and derived ingredients, preservative 12 is the only none natural ingredient I use. Is it essential? Thanks

    • PhilGeis

      Member
      June 9, 2024 at 1:29 pm

      Yes - a preservative is essential and a chelator is part of it. try phytic acid

      • OliviaLeigh

        Member
        June 11, 2024 at 6:22 am

        Hi - So why I asked why the chelator was essential was a moisturiser I now sell is again 99% of natural origin, using distilled water and hydrosols in the water phase with cosmetic vit c and hyaluronic acid powder. Its passed by cosmetic assessors and so far seems stable for about 8 months now. Each batch is given a 6m sell by date. I was thinking of making a couple of alterations to do with the essential oils but in no rush, would you still suggest I incorporate the chelator too?

        I will be adding a chelator to the new serum as has been advised.

        Thanks - Olivia

        • PhilGeis

          Member
          June 11, 2024 at 9:29 am

          Thanks Olivia. Your understanding is not uncommon but is profoundly inadequate. I don’t see a preservative in the formula you describe just above. Please add a chelator AND a preservative

          Please understand “cosmetic assessors” are junior bureaucrats with little knowledge of cosmetic microbiology. The concept is a product of even more ignorant regulators, the folks who brought us the total BS of PAO. Assume they’ve given thumbs up based on some version of challenge - ISO, USP, EP - tests that are not validated in any context. They do show baseline efficacy that, with clean RM’s and sanitary manufacturing, can get clean product out the door. However, The primary purpose of cosmetic preservation is protection in use.

          A 6 month sell by date is absolutely meaningless. Even if compliance (how is that enforced?), the consumer will have the product for more months, even years through which preservative stability must be maintained. Major manufacturers who validated their preservatives to in use risk establish stability for 3 years.

          Please add a chelator AND a preservative


          • OliviaLeigh

            Member
            June 11, 2024 at 9:58 am

            Hi Phil - Thank you for your reply I so appreciate having this website to come and ask experienced chemists like yourself these questions, its invaluable to me!

            I use the preservative 12 at 1% in the moisturiser - sorry forgot to add in the last message.

            So Ive been looking up chelators and the one you advised is quite expensive for 10g would Sodium gluconate work? and at what percent with the preservative 12 do you recommend?

            Thanks, Olivia

            • PhilGeis

              Member
              June 11, 2024 at 10:19 am

              Gluconic acid isn’t that great. If you hold Phenoxy/EHG to 0.80% or less would you consider 0.1% EDTA? You’d still be 99% natural.

            • OliviaLeigh

              Member
              June 11, 2024 at 1:17 pm

              Hi Phil- Yes I could try that …so just to be clear no need for the preservative combo to add up to 1%… o.8% Phenoxyethanol EHG, Plantaserve E, Euxyl PE 9010, Preservative 12- learning! 🙂 plus 0.1% EDTA - Is it known to cause any pH drift?

            • OliviaLeigh

              Member
              June 11, 2024 at 1:27 pm

              Is this the right one? - EDTA Disodium salt dihydrate

            • PhilGeis

              Member
              June 11, 2024 at 6:23 pm

              If it goes into solution. Sorry for one more - did we talk about benzoate earlier too?

            • OliviaLeigh

              Member
              July 3, 2024 at 10:25 am

              Hi Phil - Sorry I was meant to reply but probably got distracted!

              So I got Sodium Phytate finally and I just wanted to run by the amount I should use with PE 9010 - The recommendation for SP is 0.05 - 0.5, should I use in addition to the 1% PE 9010 if so, how much? Or reduce the preservative and replace with chelator to make back up to 1% 🙂 I have vit c and hyaluronic acid powder in the formulation with well sourced and supplied plant based oils, essential oils, butters and hydrosols - Thanks 🙂

    • Graillotion

      Member
      June 9, 2024 at 2:40 pm

      If it makes you feel any better, use the PE 9010 at .85% and the chelate at .15%….and bingo….you have elevated your preservation beyond belief…and not changed your ratios. 😉

      Another one that can usually be passed off on those that don’t understand chemistry is… GLDA, aka TSGD.

      Good luck.

      • Graillotion

        Member
        June 9, 2024 at 2:43 pm

        Do you have any idea…. how much edta you eat every day…should you partake in any type of processed food? 😂

        • OliviaLeigh

          Member
          June 11, 2024 at 6:53 am

          Ive done a little more research and thought I should add I do used Rosemary CO2 exract at 0.1% and citric acid for pH adjusting which i see is also classed as a weak chelator, will this help with preservation without a chelator? Only asking because I use this combo in my moisturiser I sell already and has passed assessment.

          • OliviaLeigh

            Member
            June 11, 2024 at 7:03 am

            … Rosemary CO2 only good for the oxidation in oils!! Sorry getting in a muddle 😀

        • OliviaLeigh

          Member
          June 11, 2024 at 7:01 am

          I found sodium gluconate could I use this in combo with Preservative 12 as you suggested?

      • OliviaLeigh

        Member
        June 11, 2024 at 6:39 am

        Hi

        Thank you 🙂

        So I quickly found a UK supplier for EDTA Disodium salt dihydrate 100%, could I use this at 0.15% with the preservative 12? Finding it harder to find Phytic Acid, GLDA :D. I havent looked hard enough though.

        Any other suggestions? Im UK based and I really want to elevate my preservation! Now I know I can never turn back! Every day is a learning day 😀

        Thank you again!

        Olly

        • PhilGeis

          Member
          June 12, 2024 at 3:40 am

          Good luck! Appreciate your concern for your customers safety.

  • PhilGeis

    Member
    July 3, 2024 at 10:40 am

    ok

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