*Cosmetic Preservation and why it’s important* A Thread

So let’s start with the basics. What exactly is a preservative? It is a substance/chemical that helps control microbes that can enter products through the raw materials, during manufacturing, and through consumer usage and handling.

When it comes to microorganisms there are at least two classes that are a problem in cosmetics: Bacteria and Fungi. Remember there are several microorganisms under each category and not EVERY microorganism can be seen with the naked eye!

To understand why preservatives are in cosmetics you need to understand the foundation. Last time I talked about the requirements for microbial growth. It can be divided into physical and chemical requirements. Here’s a summary:

Now what is the goal of using preservatives? Instead of providing microorganisms with the ability to grow, we are REMOVING any possibility for them to grow. That means making a product at a non-optimal pH, temperature, using biocides, etc.

The MAIN reason preservatives are added to cosmetics is to PROTECT THE AQUEOUS PHASE. Remember when I told you that microorganisms like to grow in water? By protecting the water phase this will lead to a LONGER shelf life for your cosmetics

Not all cosmetics will have an aqueous phase so technically, preservatives aren’t ALWAYS needed, however if you have an anhydrous product that will come into contact with water at some point, preservatives will SAVE YOU

If your cosmetics that have an aqueous phase do not have a preservative or do not have some type of preservative system that is protecting it, this will lead to a SHORTER shelf life and HIGHER chance of contamination. We don’t want that

When it comes to preservatives, there is NO preservative that works in every formula and on everyone (yes, that even includes parabens) BUT there is a guideline that chemists try to go by when selecting preservative(s) for a formula:

When you see a preservative on an ingredient list, it is not necessarily JUST acting as a preservative for your cosmetics. It can also serve several other functions. Example: Citric acid may be used as a preservative, exfoliant, pH buffer..

This is why I tell y’all not to read an ingredient list at face value! You never know why an ingredient is in a formula! This is not to discourage you from looking at the INCI BUT keep in mind an ingredient list does not tell you everything

Another thing to take note of: the synergistic effect! The synergistic effect is an effect produced by the combination of ingredients where it is GREATER than the sum of effects of each component taken separately. Let me give you an example:

Let’s say I’m cooking chicken, instead of adding salt to one chicken and pepper to another chicken, I notice that a COMBINATION of salt and pepper had a greater effect on the flavor of the chicken compared to just seasoning them separately

A common example of synergy with preservatives that you will see on your ingredient list is phenoxyethanol and ethylhexylglycerin. These two preservatives are almost ALWAYS used together because they have proven and tested synergy.

After preservatives are added, they SHOULD be tested to see if the preservative system is GOOD ENOUGH to protect the formula. Not every brand tests their products to see if the preservative system is good so imagine what can happen..

Overall, the goal of testing preservatives is to use the least amount of preservatives that will kill microorganisms in a certain amount of time. If it does not kill them off within this time, the system is not good and needs to be fixed

Even if your cosmetics do not contain a preservative there are ways chemists can prevent microbial growth. So when you look at an ingredient list and don’t see a preservative don’t be afraid. There are ways around this. Here’s a summary:

Lastly, here is a take home message to think about: There is ALOT of fear mongering about preservatives. They are not bad. Preservatives and the LEVELS they are used in cosmetics are demonstrably safe (including parabens).

But when people continually demonize the preservatives that work, that leads chemists to use something that may not be as effective and may not even be safe. The more demonizing there is, the less options we will have to work with.

That’s all I got for today! Stan preservatives for clear skin