Safe Handling of Cosmetic Ingredients

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Making cosmetics at home has become a quite common thing in the last years, there are more and more suppliers of cosmetic ingredients and more and more ingredients are becoming available to the DIY homecrafter.
However, while the will to make cosmetics has increased significantly, the same cannot be said about the will to understand and study exactly what we are dealing with.

[I have written already a post on the most common mistakes people do when they start making cosmetics at home, you can read it here… repetita iuvant!]

The toxicity of common cosmetic ingredients can be extremely high.

Being too comfortable around cosmetic ingredients is a dangerous thing. Even people who work in the cosmetic industry risk getting too comfortable around the ingredients, but at least they know about these risks.

Unfortunately I have seen online many people comparing the making of cosmetics at home to simple cooking, and if this could be true to some extent, it is also true that the cosmetic ingredients we commonly use are much more toxic and much more concentrated than any food item we might deal with. A simple example: caffeine can be deadly if ingested above a certain amount and when making cosmetics we usually handle its pure powder form.

Here are a few important points to consider:

– Storage of Cosmetic Ingredients: 
Many suppliers of cosmetic ingredients don’t send the ingredients in safe containers. Sometimes I have received powder ingredients in thin plastic bags, tied with a knot. Needless to say, I have ever since avoided these suppliers, but the first thing I did upon receiving such badly packaged ingredients, I put them in a proper container, with a tight and good lid. If I had a glass container, that would be my first choice, but sometimes I had to use plastic as well. I then labeled the container with the INCI name of the item, the supplier name, and the date of expiry.
Ingredients should be stored in a dedicated space, absolutely well separated from food items.
Serious suppliers do this labeling job before shipping the ingredient.

Sometimes I have had to create dangerous liquids, for example the bottle containing 18% Sodium Hydroxide solution (for modifying the pH). This solution is dangerous but is pretty odorless and transparent which makes it even more so. For such bottles or jars I write “VERY DANGEROUS” on the bottle, using a red marker, and I have also painted skulls on the lid and all sides so that it would be apparent even to any other person coming in contact with this jar or bottle that it is definitely not a water bottle and not something that should be drank or used for cooking (even if, of course, such jars and bottles are NEVER kept in the kitchen or near a cooking space).

• Preserving systems:
  I keep seeing posts written by people who dislike preservatives simply because they are “poison” (their words) and this actually gets me because: yes, preservatives are not fresh water and therefore they need to be handled carefully, but they are essential if you are adding water to any of your cosmetics (and sometimes they should be added even in anhydrous formulas).
  I have had multiple people write to me that they chose to not add a preserving system to their formulas and they were perfectly fine. They usually write something similar to this: “My cosmetic is just fine: there are no visible signs of mold or bacteria, no change in smell nor color…”. Well, trust me, there is no way you can tell by simply staring at your cosmetics if they are full of bacteria/mold or not.
  Let’s make some healthy scaremongering: badly preserved cosmetics can lead to blindness and even death (no joking here – check online news).
  If you are on your own formulating cosmetics journey, like I am, I hope you understand that preserving your formulas is absolutely essential.
  I have been thinking about writing a post on preserving systems but I do not feel I have the skills to do that in a comprehensive way, so please do study about this from other sources.
• GMP – Good Manufacturing Practices
  If you are on your formulating cosmetics learning trajectory, then one of the first things you should learn about is also GMPs. Of course the industry has very strict rules and regulations, and for a good reason. While my equipment is not of the industrial scale and I use a mixing blender instead of the proper mixers and omogenizers, I do my best to follow all the best practices that try to ensure a successful formulation in the end. For example I use 70% isopropyl alcohol to clean and wipe all the equipment before using it, including jars, bottles and lids (with an extra care to not wipe it away immediately but giving it a little time to actually do its job), using goggles, gloves, my lab vest. Not allowing pets, kids, even teens, in the spaces while formulating. Having separate beakers, jars, bottles, spatulas, stick blenders totally dedicated to the formulating of cosmetics and nothing else. These are, in a sense, common sense practices as well. But yet again, even if I follow all the possible GMPs I can follow in my home setting, I am always very aware that no amount of GMPs can substitute proper testing of the final result. This means that as much as I can follow GMPs, I can never be sure that what I have made is properly homogenized, or properly preserved, or that the ingredients were in fact stored properly in all their life cycle (who knows, maybe during the shipping something went wrong, the truck was in the sun for too long, for example). So risks are always present. All I can do is to try and limit the dangers by following good GMPs.
• Handling Acid and Alkaline ingredients:
  If you don’t know what the pH is, don’t care to learn about it, don’t have a way to measure it… I would highly suggest you not to start formulating your own cosmetics.
  These are dangerous ingredients, when added to a cosmetic they should always be buffered and they need to be handled with special care (as always, following GMPs, wear goggles, wear gloves, wear long sleeves, don’t allow any distraction when using them (no kids, pets, whatever might come in the way)).
  When dealing with ingredients that have pH<2 or pH>12, you are dealing with ingredients that are so willing to react with water that if they touch the skin they are going to use whatever water they find in it: this is how they “burn” the skin.
  But while Acids hydrolize proteins and create a hard necrotic barrier that stops themselves from entering the skin any further, alkaline ingredients instead saponify the fats in the skin (those of you who make soaps should already be acquainted with this), creating a soft necrotic tissue that lets hydrogen ions penetrate further and create more damage. It is possible to assess the severity of the contact with an acid after few hours, but with an alkaline substance it can take even 2 to 3 days.
  What I do if I come into contact with these substances despite following GMPs:
  – immediately wash under running water (for a long time – at least 15 minutes)
  – I would call the doctor (specially if the drop hit the eyes) – this hasn’t happened to me thus far
  – do not rub the eyes: the damage will be greater
  The damage is proportional to the concentration of the substance, the area of contact and the time it was left there.

– Ingredients and pH
The importance of the pH is not only with regards to acids and bases: any ingredient cosmetic ingredient has a preferred pH range at which it should be used and this might create incompatibilities with other ingredients.
I have already talked about it in the post about pH, but let’s say it again: while some substances will simply not work well if one doesn’t respect their pH range (high molecular weight hyaluronic acid for example, or even carbopols which work well only around pH 5-6), other ingredients can become really nasty.
It is the case, for example, of Urea (never above pH 6) and Niacinamide (good between pH 6 and pH 7.5).
If you are learning about cosmetic formulation, you need to learn about each ingredient you intend to use way before you start formulating with it. Research for incompatibilities with other ingredients and research the suggested pH range of use.
Avoid mixing too many ingredients, specially if you have just started making cosmetics (I know it is tempting): try making simple cosmetics instead.

– Ingredients and their concentration
Also concentration can be critical: adding a higher percentage of an ingredient to a formula compared to what is suggested in the MSDS is never a smart idea.
The least damage you will do will be wasting the ingredient: Q10 suggested concentration of use is 0.1%. If you add 1% to a formula, you will make the formula very expensive but it won’t be more effective. You will simply end up having a very yellow cream and a waste of 0.9% of the ingredient.
But it can get worse than this with certain ingredients: alpha-bisabolol is a very good, soothing ingredient at 0.5% but it can irritate at 1% or above. Glycerin is hydrating if used around 5%, but it might dry the skin if used at higher concentrations. Allantoin is a lovely film-forming, hydrating and soothing ingredient but its solubility in water is limited to 0.5%. If you add 1% it will form micro (and not so micro) crystals that can actually damage your skin when you apply the cream.

Making cosmetics at home is an amazing thing, but it has real risks!
So, if this is what you want to do, get books about cosmetic formulation, learn about it, study, research the ingredients and use proper GMPs to try and mitigate any risk.
That’s all for today!
Hope this was helpful and good luck on your journey 🙂