Home Cosmetic Science Talk Formulating Your thoughts on the preservatives in these big brand formulas?

  • Your thoughts on the preservatives in these big brand formulas?

    Posted by GeorgeBenson on April 26, 2022 at 6:17 am

    Was browsing through sephora and looking at the ingredients on a couple popular products…and i dont know much about anything but a lot of them dont seem to have the strongest or most complete preservative system. Was wondering what your thoughts are on these and how they’re accomplishing it? Must be working for them somehow though right because they are on sephora…maybe I’m just not recognizing certain preservatives they are using.

    Water/Aqua/Eau, Glycerin, Propanediol, Dipropylene Glycol, Niacinamide, Betaine, 1,2-Hexanediol, Carbomer, Tromethamine, Ammonium Acryloyldimethyltaurate/Beheneth-25 Methacrylate Crosspolymer, Disodium EDTA, Ethylhexylglycerin, Fragrance/Parfum, Prunus Yedoensis Leaf Extract, Tocopherol.

    Water/Aqua/Eau, Butylene Glycol, Glycerin, Trehalose, Methyl Trimethicone, 1,2- Hexanediol, Squalane, Phenyl Trimethicone, Pca Dimethicone, Caprylyl Methicone, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Lactobacillus Ferment Lysate, Carbomer, Propanediol, Tromethamine, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Glyceryl Caprylate, Ethylhexylglycerin, Disodium Edta, Raffinose, Stearyl Behenate, Malachite Extract, Fragrance/Parfum, Polyglyceryl-3 Methylglucose Distearate, Inulin Lauryl Carbamate, Tranexamic Acid, Tryptophan, Hydroxypropyl Bispalmitamide Mea, Beta-Glucan, Limonene, Acorus Gramineus Extract, Linalool, Tocopherol.

    PhilGeis replied 2 years, 6 months ago 7 Members · 16 Replies
  • 16 Replies
  • Camel

    Member
    April 26, 2022 at 8:01 am

    My best guess is that they are using a combination of a high percentage of humectants and preservative boosters. Glycerin, propanediol, hexanediol, butylene glycol, dipropylene glycol… as well as ethylhexylglycerin, glyceryl caprylate and disodium edta, which can all boost preservative efficacy. 

    I’m not sure how well it works without an actual preservative (at least, I don’t recognize one on the list), but I’m hoping they at least did proper testing if they are big enough to be sold at Sephora. 

    Would love to hear what the experts think. 

  • GeorgeBenson

    Member
    April 26, 2022 at 8:58 am

    @Camel how do humectants like glycerin and propanediol help with preservation? Not doubting you I just honestly dont know.

  • Graillotion

    Member
    April 26, 2022 at 9:07 am

    @Camel how do humectants like glycerin and propanediol help with preservation? Not doubting you I just honestly dont know.

    They lower the water activity…. Good research project for you. :) 

    You know…any product that has enough glycols…can be self-preserving.  Lots of the extracts and the likes sold on by repackers…are preserved with this method.

  • grapefruit22

    Member
    April 26, 2022 at 9:11 am

    I have a few Korean products with 1,2-Hexanediol & Ethylhexylglycerin used as a prevention against the growth of microorganisms, they all have PAO 12 months, so at least they were tested. In my understanding, they only protect against growth, so if the bacteria get into the package, they won’t be killed. Recently, someone recommended this preservative to me for a face toner. I’m curious about the opinion of experts.
    I know at least one brand that doesn’t have PAO or an expiration date on their packaging and is sold at big retailers.

  • Camel

    Member
    April 26, 2022 at 9:20 am

    @Camel how do humectants like glycerin and propanediol help with preservation? Not doubting you I just honestly dont know.

    They lower the water activity; the higher % of humectants you have, the lower % of free water there is in the product. Humectants like propanediol have even been shown to boost the efficacy of preservatives. 

  • Abdullah

    Member
    April 26, 2022 at 10:17 am

    They may also have airless package to helps preservation

  • grapefruit22

    Member
    April 26, 2022 at 10:32 am

    Products mentioned by George are in jars. 

  • PhilGeis

    Member
    April 26, 2022 at 11:01 am

    Sephora policy prohibits use of classic preservatives.   They’ve provoked many recalls (search Sephora and recall).  Don’t take preservatives systems of products they sell as models

    Those are garbage preservative systems, esp. for jar packaging.  Humectants at cosmetics levels  do not effectively lower water activity to effect preservation level performance.  “Self preserving” with ’em is BS.   
    Hexanediol can be useful at high (%) levels vs Gram negatives, less so vs Gram +’s and limited vs fungi. 
    EHG is a booster with phenoxyethanol.  Beyond that it is not know n to have a significant effect.

    Do not presume PAO means anything. 

    Please remember, you guys and Sephora’s suppliers use the classic USP style test.  It is validated to nothing - not consumer use and certainly not to manufacturing. 

  • grapefruit22

    Member
    April 26, 2022 at 11:17 am

    @PhilGeis, so how should products be tested? Laboratories don’t offer tests other than ISO 11930, Pharmacopoeia and Schülke Koko Test.

  • PhilGeis

    Member
    April 26, 2022 at 11:35 am

    They should be designed to be safe - formula, package and manufacturing.   Available testing is confirmatory not discriminating and only considers one element.

  • PhilGeis

    Member
    April 26, 2022 at 12:08 pm

    to the title of the original post - if you want to copy a system, look at an authentic “big brand” - Olay, Estee, etc.  Sephora is not a brand - it’s a retailer. .

  • grapefruit22

    Member
    April 26, 2022 at 12:45 pm

    @PhilGeis Looking at their preservatives in water-based products, it looks like they’re just using Phenoxyethanol and Disodium EDTA. What are your thoughts on the combination: Phenoxyethanol + Ethylhexylglycerin + Chlorphenesin + Tetrasodium Glutamate Diacetate?

  • PhilGeis

    Member
    April 26, 2022 at 1:55 pm

    @PhilGeis Looking at their preservatives in water-based products, it looks like they’re just using Phenoxyethanol and Disodium EDTA. What are your thoughts on the combination: Phenoxyethanol + Ethylhexylglycerin + Chlorphenesin + Tetrasodium Glutamate Diacetate?

    Phenoxy/EDTA is weak.  Poor vs Gram + (staph) and fungi.
    Other combination - pretty good system esp. w/ package that prevents direct skin contact in container.   Phenoxy/EHG /chelator effective vs Gram - and Chlorphenesin for fungi but a combin. a little weak for staph.

  • grapefruit22

    Member
    April 26, 2022 at 2:39 pm

    If  Phenoxy/EHG are used at 1%, chelator at 0,1%, formulation has also propanediol at 5%, then Chlorphenesin should be used at 0,3% or lower?
    Big brands use glass bottle + dropper, is it a good packaging? There is no contact with product, but there can be contact skin-dropper, and then dropper has a contact with product. 

  • natiyo123

    Member
    April 28, 2022 at 5:53 pm

    they use glycols and glycerin to lower water activity and they also have chelators… their preservation is quite good actually, at the same time avoiding “controversial” traditional preservatives.

  • PhilGeis

    Member
    April 28, 2022 at 6:13 pm

    natiyo123 said:

    they use glycols and glycerin to lower water activity and they also have chelators… their preservation is quite good actually, at the same time avoiding “controversial” traditional preservatives.

    That is incorrect.  Glycols and glycerine at use concentrations do not lower Aw sufficiently to preserve and those are garbage, politically-correct  systems.

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