sunscreen with zinc oxide

[wxz123]

Does anyone knows how much zinc oxide I need ( % ?) to make a 30 SPF lotion?
Thanks

 

[Deda]

Is your zinc micronized?

 

[wxz123]

I am not sure what that means??

 

[Deda]

Different places sell different kinds of Zinc Oxide powder, micronized is a smaller crystal.

You need less micronized zinc oxide than non-micronized.

 

[wxz123]

ok, than what if its micronized....how much should I use for 30 SPF?

 

[Deda]

Sorry, sick today - forgot to answer.

Use 20% of micronized and 25% of non-micronized.

(for homemade only - if you want to sell it you must comply with FDA drug monographs and have your formulas lab tested.)

 

[wxz123]

No problem

Do I really have to tested in lab before selling? i did not have a clue :roll:

 

[Deda]

Oh, yeah, SPF is a drug claim. Whole new ball game.

 

[wxz123]

Do you know where I can test it?? I would really appreciate!!!

 

[Deda]

You need to start by doing some research at the FDA.

 

[IanT]

glad you posted this... Ill have to look into this as well