Home Cosmetic Science Talk Formulating Sufficiently preserved?

  • Sufficiently preserved?

    Posted by Rmecca on April 6, 2023 at 11:05 pm

    Hi all, I’ve recently decided I want to try formulating some of my own personal care items and I’m taking a look at products I currently enjoy to get a baseline. However I also have been doing a lot of reading here on preservation systems, and I’m wondering if two products I use are sufficiently preserved. They are marketed green/natural/etc and I’m starting to get wary of that when it comes to preservation. Without knowing amounts, just the ingredient lists, how do these look?

    Face cream by Oneka:

    Water (Aqua), Aloe Barbadensis Leaf Juice (Aloe Vera), Calendula Officinalis (Marigold), Polyglyceryl 1-2 Dipolyhydroxystearate, Fucus Vesiculosus (Seaweed Extract), Ricinus Communis (Castor Seed) Oil, Xanthan Gum, Theobroma Cacao (Cocoa) Seed Butter, Rosa Canina Fruit (Rose Hip) Oil, Hypericum Perforatum (St.Johns Wort) Oil, Tocopherol (Vitamin E), Vegetable Glycerine, Panthenol, Hippophae Rhamnoides, (Sea Buckthorn) Oil, Polyaminopropyl Biguanide.

    I only see polyaminopropyl biguanide (aka polyhexamethylene biguanide, PHMB). Can this preservative be used effectively as the sole preserving ingredient? Based on my limited reading it seems that it is effective vs gram negative/gram positive bacteria as well as yeast and mold. If that’s true and it doesn’t need other preservatives/boosting ingredients, is there any reason this doesn’t feature on more ingredient lists? I feel like I don’t see it very often. Or, should this product ideally have other ingredients in the preservation system?

    And the product I’m most worried about, a body wash by Alevia:

    Filtered Water, Coconut Oil, Aloe Vera, Dead Sea salt, Acadian Sea Kelp, Citric Acid, Plant Glycerin

    There’s nothing in here that can actually preserve…right? I know salt, acid, and glycerin can have some antimicrobial activity but I highly doubt any of these are in high enough concentration. I quite like this body wash. It purports to be gentle to the skin’s microbiome. I have noticed a decrease in clogged pores on problem areas of my skin since switching to this body wash. I would love to recreate this, but properly preserved.

    In reading through this forum, I’ve come across a few preservation systems that have been recommended in an oil in water emulsion (which I think this is?) that also avoid parabens/formaldehyde releasers, which I’d like to avoid. I know it’s impossible to predict based on ingredient list alone, but does the addition of the following seem reasonable?

    0.5% phenoxyethanol (appears that 0.5% is recommended here just as well as 1%)

    0.05% ethylhexylglycerin (booster, keeping in line with ratio found in Euxyl PE 9010)

    Some amount (not sure how much?) of phytic acid (chelant) and sodium benzoate (to help with yeast/mold/fungi)

    pH 4.6-4.8

    Any help with assessing the preservation system of either of these products, or feedback on how to make them safer if necessary would be much appreciated!

    PhilGeis replied 9 months, 1 week ago 5 Members · 8 Replies
  • 8 Replies
  • PhilGeis

    Member
    April 10, 2023 at 1:45 pm

    Oneka is silly. I’m more familiar with PHMB but Biguanides are good for swimming pools, poor in cosmetics.

    Phenoxy/EHG/chelator/Benzoate at that pH should be ok.

  • Rmecca

    Member
    April 17, 2023 at 1:42 pm

    Thank you! What about polyaminopropyl biguanide makes it more suitable for pools and less for cosmetics? Is there a safety issue or is it just more suited for the types of microbes that would be a problem for pools?

  • PhilGeis

    Member
    April 17, 2023 at 4:07 pm

    Pools as simple water solution without the cosmetic poo and goo and biguanides are substantive - cosmetic packaging offers much more surface area to a small volume of product.

  • Rmecca

    Member
    April 19, 2023 at 3:00 pm

    Thank you for the explanation!

  • Unknown Member

    Member
    April 24, 2023 at 11:01 pm

    Pools that are just water without any biguanides or other cosmetic additives are actually quite beneficial. geometry dash scratch

  • Unknown Member

    Deleted User
    April 28, 2023 at 5:03 am

    I’m not too familiar with PHMB as a preservative, I tend to stick to the more traditional and well-known preservatives, even if the end customer doesn’t like them, as we know they are reliable.

    I would also be concerned about the body wash. Not only because it is not preserved, but also because all those natural ingredients, especially coconut oil, are known to introduce microbes into a formulation. There is a higher tolerance when it comes to QC testing for natural ingredients on microbial content than many other raw materials.

    I’m also confused as to how it cleanses the skin with no surfactant content; you almost may as well use water on its own! And how is the coconut oil emulsified into the formula? It must be floating on the top, or there is an emulsifier in there which they have not listed. If the product is not hazy and coconut oil is not floating on the surface, then it must be at such a low concentration and the ingredients thereafter are also included at a minute level; you are being conned into buying filtered water if you are purchasing this product!

  • Story

    Member
    May 6, 2023 at 7:20 pm

    For the Body Wash, they’re only listing the active ingredients. Is that all that’s on the label? There’s no way these are all the ingredients!

  • PhilGeis

    Member
    May 7, 2023 at 3:19 am

    ALL ingredients must be listed with very few exceptions - e.g perfume ingredients.

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