Home Cosmetic Science Talk General Science OSU Zinc Study (mixed spf filters)

  • ketchito

    October 25, 2021 at 2:27 pm

    @JMc That’s one of the risks of using uncoated inorganic filters. Both TiO2 and ZnO are catalysts (TiO2 being more active than ZnO). So, the best way to avoid (or at least delay) photocatalitic reactions in your sunscreen is to use coated inorganic filters (stabilized with alumina and coated with some fatty ingredient to increase dispersibility), antioxidants and excited state quenchers.  

  • PhilGeis

    October 25, 2021 at 3:04 pm

    Wonder at use of DMSO.  Maybe pharma can comment -  didn’t see that factor controlled.

  • oldperry

    October 25, 2021 at 7:46 pm

    Yeah this seems like it’s pretty much a scientist ignorant of how sunscreens are actually made (using coated zinc oxide) “discovering” something that industry has known about and solved decades ago.

  • JMc

    October 25, 2021 at 8:31 pm

    Yeah - I had the same feelings. Thanks all! Hopefully it will blow over (but I feel like it’s definitely another week I’m glad I hang out in the lab and don’t handle the CustServ calls, lol). Cheers :)

  • Shams

    October 26, 2021 at 2:10 am

    Hi @Perry & everyone else.
    I also came across these links.
    I am a bit confused and seeking clarification please: 
    Does this study apply only to sunscreens where a combination of ZnO + other organic UV filters are present or even if ZnO is used alone.
    @Perry Are you able to please share links for the safety of coated and uncoated ZnO

  • oldperry

    October 26, 2021 at 5:13 am

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