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  • Preservatives with low irritation

    Posted by Anonymous on February 6, 2020 at 12:48 pm

    Hi there! 

    I am working on my own skincare line and currently have a gel cleanser with Potassium Sorbate, Sodium Benzoate, and citric acid as my preservatives and for my light moisturizer I am unsure, can I use the same? 
    Do you have any experience with irritation with these preservatives? 

    I would like to know your thoughts! 

    EVchem replied 4 years, 2 months ago 3 Members · 3 Replies
  • 3 Replies
  • OldPerry

    February 6, 2020 at 1:31 pm

    That depends on what ingredients are in your light moisturizer.
    Citric acid is not a preservative. You should also have a chelating agent in the formula (like Disodium EDTA).

    You would get more helpful answers if you listed all the ingredients in your formula.

  • alchemist01

    February 6, 2020 at 3:53 pm

    Sodium benzoate and citric acid are not a good combination. At low pH or in generally poor storage conditions (excessive light, heat, etc.), citric acid can cause the benzoate to decarboxylate into benzene, which is highly carcinogenic. 

    If using sodium benzoate I would also take Perry’s recommendation and add a chelating agent, because metal ions can also catalyze benzene formation. It’s actually for this reason that you find EDTA in Coca-Cola.

  • EVchem

    February 6, 2020 at 7:35 pm

    That hasn’t been found conclusive (Sodium benzoate + ascorbic acid) as far as I know

    In November 2005, FDA received reports that benzene had been detected at low levels in some soft drinks containing benzoate salts and ascorbic acid. CFSAN immediately initiated a survey of benzene levels in soft drinks and other beverages. The vast majority of the beverages sampled to date (including those containing both benzoate salts and ascorbic acid) contained either no detectable benzene or levels well below the 5 ppb EPA MCL for benzene in drinking water.

    Never hurts to have a chelator though (though if it is a salt it can interfere with emulsion)

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