Cosmetics Under the Microscope, Microbes and Mi...

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Cosmetics Under the Microscope, Microbes and Mini-Beasts

Mention the phrase 'safe cosmetic' to someone and they will most probably reel off a selection of ingredients that they don't want to put onto their skin. While the 'toxins in, toxins out' populist philosophy has some merit the biggest risk posed by your cosmetic obsession lies elsewhere in the land of microorganisms.

The problems arising from Microbial contamination are very real for cosmetic brand owners who essentially produce micro-feeding broth every time they put that water in a bottle or jar and try to sell it. Practically everything that we label as a cosmetic product could fall foul of micro contamination, which is why it pays to have a plan...


Ignorance is not bliss.

Before I go on I will say this, many small brand owners that make products for market stalls, in small batches or who have only just started making their range feel happy that they don't have a problem because they have never seen anything growing or smelling off! Like with many things in life the fact that you haven't seen any microbial growth or change with your own eyes doesn't mean it doesn't exist. In fact, you could be storing up a whole host of problems especially as many of the pathogenic bacteria don't look like anything at all until they grow so numerous that your product falls apart. Stability issue or micro fail? It is very hard to tell without testing...

So what should you do?

1 ) Risk assesses your ingredients.

Synthetic oils, refined vegetable oils and other oily materials (emollients etc.) are low risk, as bacteria, yeast and mould need water to live and these ingredients area water-free. However, low risk doesn't mean no risk and as such oily ingredients should still be stored in clean, dry and temperate conditions to keep them clean.

Unrefined oils, specialty unsaturated oils, butters and waxes are slightly higher risk and should be monitored for signs of rancidity.While these are also water free their instability (unrefined oils and unsaturated) and/or their surface area allow a doorway for potential micro issues.

Dry powdered ingredients such as clays, micas, herbs and exfoliating particulates can be particularly troublesome as their large surface area paired with their porosity (clays) or organic matter (natural exfolliants or herbs) gives fungal spores a great little hiding spot.Irradiation or UV treatment before use can help clean these suckers up!

Any ingredients that contain water including water its self will need special attention too and are often preserved by the ingredient manufacturer before you get to them. That said careful handling and ingredient testing is recommended for larger batches.

2) Be careful with your mixing.

In a factory setting we abide by Good Manufacturing Practice guidelines such as those laid out in the international ISO standard. At home or on small-scale production plants it isn't always practical to have everything documented so that it can be audited but that doesn't mean you shouldn't have a robust manufacturing procedure. Making sure that your workbenches are clean, equipment sterile and air free from particulates is a great start as is personal hygiene and handling (wear gloves and a hair net and lab coat).

3) Check packaging.

Your finished packaging may be another source of contamination as it is easy for airborne particles including microbes to fall into open boxes of containers and sit waiting to be hydrated by your cosmetic product. It isn't always best to sterilize the containers before use - it really does depend on where they have come from, if you bought a full box or not and what is going into them. You won't know how clean the packs are if you don't swab them and get a micro count but having an understanding of the risk and levels of risk will help you make a plan of action.

If you do need to sterilize any equipment or packaging you will have to look into an appropriate broad-spectrum anti-microbial cleaning solution. Alcohol at 70% in water is a decent all-round cleaner but may not get everything sterile. Baby bottle cleaning solutions or hospital disinfectants may be a better option in some cases.

And then what?

Once you have assessed the potential risks around each of your formulations and manufacturing protocols you can start to think about investing in testing.

Micro testing of cosmetics takes two general forms - the Micro count and the Preservative Efficacy Test (PET).

A Micro Count will do what you would expect from the name - it counts the number of microbes that can be found in a sample. This count is good as it gives you a snapshot of the cleanliness of your product, packaging or ingredient. However, being only one moment in time it won't give you much of an idea of how the product will stand up to use. For that we need the PET.

Preservative Efficacy Testing puts your product through its paces in terms of how robust it is against micro contamination. This is essential for leave-on skin care products, anything to do with babies, the elderly, very dry skin conditions, acne, eye products, products for pregnant women or children's cosmetics to name but a few.

A sample of your product is challenged by introducing a set dose of microbes at regular intervals and seeing if the microbes thrive, sit without growing before eventually dying or dying immediately. A pass here will mean that your formula stands a good chance of performing well in-use.

Preservative Efficacy Testing is expensive and depends on the protocol chosen (you can test to BP (now EP), USP or the new (2012) ISO 11930 standard) but it is arguably the most crucial test of all to do on your product especially when you are creating a new formula, have changed your packing to something more risky or are making the product in a non-GMP facility.

It is usual to carry out your PET on a manufactured batch when the product is being launched as a final step in the R&D process. In some cases where a product has a long shelf life or may last a long time (due to large packaging or small dose size) it may be necessary to run further PET as the shelf life progresses as just as antioxidants and vitamin based actives can disappear or be used up over time so can your preservative system. This can add substantial costs to your R&D but is essential for some highly active cosmetics such as eye serums and sunscreens.

Many of our customers struggle with the costs of testing their formulations and nearly everyone tries to find a way to minimize this R&D expense. The bottom line here in Australia is that while there is no law spelling out the testing that you HAVE to do on a cosmetic there is a clear requirement for the brand owner to place products that are safe onto the market and if push came to shove and you as a brand owner can't prove your products are safe you are at a distinct disadvantage. It is likely that any product liability insurance you have will expect that you have tested your products to determine they are 'fit for purpose' and would probably not pay out on any claim if you as a brand owner couldn't present the evidence needed to back up your products. In that regard PET and micro counts act as value-adding security to your business as well as peace of mind for your customers.

So can you minimize the costs and stay safe?

It probably isn't going to be necessary to run tests on every ingredient, every batch and every formula in your range so do take the time to draw up a micro and stability risk assessment plan for your products and then talk that over with your manufacturer, formulator or testing provider. Once you have found a way of keeping your ingredients clean and manufacturing in optimal conditions your micro risk profile will drop considerably.Selecting packaging that helps rather than hinders your micro cause will also work in your favour.

So the secret to producing safe cosmetics is?

It is simple really. It doesn't pay to ignore the fact that microbial contamination is your number one safety concern. Pay it the attention it deserves, take care with your formulating, manufacturing and packaging and test, test, test so that when the time comes you can sell with confidence knowing that yours are safe cosmetics.

Amanda Foxon-Hill

13 June 2014

More about: Cosmetics

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