Home Cosmetic Science Talk Formulating Pregnancy and Safe Sunscreens

  • Pregnancy and Safe Sunscreens

    Posted by stanley on July 21, 2021 at 8:05 pm

    Besides Zinc Oxide and Titanium Dioxide (which is questionable) what other sunscreens are safe for pregnant women? 

    stanley replied 2 years, 8 months ago 7 Members · 12 Replies
  • 12 Replies
  • pharma

    Member
    July 21, 2021 at 8:46 pm

    The new ones used in Europe for example UltraSun. They’re not yet approved in the US if I’m not mistaken.

  • bill_toge

    Member
    July 21, 2021 at 8:50 pm

    most of them, apart from PABA derivatives and possibly benzophenone-3

  • stanley

    Member
    July 21, 2021 at 9:35 pm

    Not sure how to formulate with ZnO and TiO2.  Just make a nice face cream and add ZnO and TiO2 to it? Just not sure where to start on this one.

    water            89%
    carbomer       0.3%
    HEC               0.1%
    EDTA             0.1%
    bg                 1.9%
    almond oil     4.7%
    avocado oil     3.0%
    span 80-        2.0%
    pelemol bid-c 0.9%
    shea butter - 1.41%
    steric acid-    0.9%
    cetyl alcohol  2.0%
    lip gms 470   0.9%
    Vitamin E-     0.15%
    isononyl isononoate-  0.8%
    ZnO-  20%
    allianz OPT-  2.80%
    preservative- 1.00%

    My cream looked nice but soon as I put in the ZnO it turned into paste.

  • abierose

    Member
    July 21, 2021 at 10:52 pm

    Are you sure those percentage amounts are correct…? Looks like it adds up to over %100…

  • ozgirl

    Member
    July 21, 2021 at 11:31 pm
    Sunscreens are serious business and in some countries they are classified as drugs/medicines.
    If you still want to proceed you will need to have the product tested to ensure that you are achieving the correct SPF.
    It is is not simply a case of adding some ZnO to a face cream. I would recommend hiring a formulator with experience in sunscreens.
  • Bax65

    Member
    July 22, 2021 at 12:46 pm

    Regulatory approved UV filters are safe to use also by pregnant women.
    But you will need to check which filters are okay to use in the region where you want to bring your product to the market.

    I would recommend connecting to a supplier of UV filters (or their distributor). They normally have formulation suggestions available.

    General remarks about working with ZnO:
    Adding 20% of ZnO alone only gives you a relatively low theoretical SPF. Maybe something around 10 to 15. In detail this also depends on the formulation type. ZnO is not giving a high SPF but its protection is almost completely in the UVA area.

    Best way of incorporation depends if you use a coated or uncoated material. But generally: If you add 20% of an insoluble powder you will allways experience a significant viscosity increase in your formulation. Tou counteract you will need to rework the whole thing.

    But as the sum of your ingredients adds up to almost 140 you “only” added ~15% ZnO anyway.

  • stanley

    Member
    July 22, 2021 at 3:29 pm

    Thanks for the input… I understand sunscreens are serious.  That is why I am asking about the process especially when I was given parameters to work with.

    The water is 59% and not the 89.  I made the lotion first then split in half to add the ZnO. This is where I got the paste.

  • chemicalmatt

    Member
    July 22, 2021 at 5:24 pm

    @Stanley that ZnO crash is due to  the enhanced solvation of ZnO in a surfactant system crashing the carbomer/HEC rheology. TiO2 will not dissolve significantly so it doesn’t affect it same. If you want to use ZnO try a silane coated version. Also, as @Pharma and @Bill_Toge mentioned, the organic chemical sunscreens are safe excepting the ones Bill cites. Bonus for Europe and elsewhere: they are allowed to use Uvasorb HEB, the best UVA absorber in commercial distribution while us suckers in the USA are left only with avobenzone now that the benzephenones are outta’ here.

  • Bax65

    Member
    July 26, 2021 at 10:56 am

    they are allowed to use Uvasorb HEB, the best UVA absorber in commercial distribution

    Please note that Iscotrizinol (alias Uvasorb HEB) is described as UVB absorber with some capacity in the UVA area.
    Most effective and stable UVA absorber is DHHB (Diethylamino Hydroxybenzoyl Hexyl Benzoate, alias Uvinul A Plus) - but for a US sunscreen this - unfortunately - doesn’t matter anyway.

  • stanley

    Member
    July 26, 2021 at 3:35 pm

    @Bax65
    @chemicalmatt

    This is still good information.  Thank you for sharing…
    Since we are talking about Europe and other parts of the world….does ZnO and TiO2 have any issues or limits beyond the USA?

  • bill_toge

    Member
    July 27, 2021 at 8:58 pm
    zinc oxide is best used in W/O and anhydrous products, as it’s quite basic in aqueous solution and can cause preservation issues (it fixes the pH around 7-8 and an enormous amount of acid is required to lower it)
    when used as filters, titanium oxide and zinc oxide are limited to 25% w/w in Europe, both in nano and non-nano forms
    also Tinosorb S / Escalol S / Parsol Shield (INCI bis-ethylhexyloxyphenol methoxyphenyl triazine) is a good broad-spectrum filter that behaves well in O/W emulsions, and has a transparent finish
  • stanley

    Member
    July 29, 2021 at 8:57 pm

    @Bill_Toge
    Thank you..i am not too familiar with ZnO products and how they look.  I have a few experiments but the texture was a little bumpy looking.  Not grainy at all.  I am having problems getting the batch to thicken like a viscous cream.  any suggestions?

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