One would think a water-free, powder-based, mineral make-up wouldn't need any preservative. No water = no need for preservative, right?
Except, in some circumstances, yes.
It was Olivia's detailed question about this that inspired todays post.
She was also gracious enough to allow me to share her several-part query with you, so let's get busy with her questions.
" Loose mineral makeup can get away with not having preservatives, right? However, sometimes people will wet a sponge and apply the color. Doesn't that mean a chance for bacterial growth? I find this dangerous – especially in eyeshadows. Isn't it much safer to add some type of preservative in all mineral makeup?
Also, oil may not contain any water when added to mineral makeup but I am thinking – to prevent it from becoming rancid – it would be better to add preservatives.
I guess what I am asking is, shouldn't makeup – no matter what form – contain some preservative as a safety measure?"
Olivias observation that some people introduce water to 'dry' make-up is an excellent point and does indeed give cause for concern.
To answer your questions:
Dry Make-up and Preservative - Commercially MadeCommercially made make-up will have a preservative added – regardless of whether or not it is an anhydrous formula. Check the ingredients list of any powder make-up and you will find there is indeed preservative added.
However - that doesn't mean you can introduce a wet sponge to a dry powder and expect the formula to stay fresh for very long. Dry make-up is rarely preserved with a broad-spectrum preservative - which is imperative if water is introduced to the product.
Dry Make-up and Preservative - Home-CraftedIf your own home-crafted make-up is water-free and the make-up does not risk coming into contact with moisture at all (wet sponges, etc) or other users, then it is not necessary to add preservative.
However - water-free make-up without preservative should ideally be used/replaced after 6 months. If you are very meticulous about cleanliness (using clean brushes, never dipping fingers into the mixture etc), then you might use the make-up up to a year.
My own water-free make-up has no added preservative. I use predominately jojoba when choosing oil. Aside from lasting longer than most oils, it is very well tolerated and has a neutral scent. I will on occasion save a container of make-up for a period of time after use - purely for observation.
Oil in mineral make-up - How about Rancidity?Some pressed powder make-up types (foundation, blush, eyeshadow etc) are made up of a combination of powders with oil as a binder. It is possible to retard the rancidity of the oils by adding vitamin E.
However - vitamin E is not a preservative, so if it's preservative power you want, you need to add preservative.
How About Natural Preservatives?Olivia also asked about how 'natural' preservatives such as rosemary extract stack up against commercial preservatives.
I did a blog post on this right here in 2013 that hopefully answers this question.
Commercial Cosmetics Going BadFinally, Olivia made an interesting observation about store-bought make-up. Her experience was that make-up no longer seemed to last 'as long as before' – that it seemed to go bad and/or smell rancid in a shorter period of time.
My theory as to why this happens: most companies have opted to replace the paraben preservatives in their products due to the paraben paranoia scare campaign. Consumers are now paying the price and having to replace make-up more frequently.
(find links to LisaLise posts on parabens here)
Do TellHave you ever experienced commercial make-up go bad? Please share in a comment below.
PS: Visit Olivia at The Unknown Beauty Blog for make-up tutorials, tips and inspiration.