Preservatives

The what, why and where of our use of preservatives in creams. 

by Monica Wilde
1 November 2014

 

Sadly in any product where water is a component, bacteria will breed. Preservatives have to be used to prevent this happening. Preservatives are the subject of much controversy and people often ask us why we use this or that ingredient. When a new story about a preservative hits the headlines we are also asked why we don't just drop the product immediately. Hopefully this article will help to explain.

At Napiers the Herbalists we do not just make beauty products for normal skin types. We provide skin care products to many people who suffer from skin irritation, eczema and other skin conditions that make their skin particularly vulnerable. It is vital not to infect their skin with bacteria and make their condition worse. With creams formulated to be used on irritated or broken skin, it is critical that we use an effective preservative to prevent bacteria growing in an open jar of cream. The Cosmetics Regulations also govern the way that these tests are done.

Unfortunately we do have to use a preservative. Very mild preservatives (sorbates, herbal extracts) do not keep the levels of bacteria sufficiently low enough. They are fine for use in purely cosmetic products but not for functional skin care products. Ointments, salves, balms and oils often don't contain preservatives because there is no water in these oil based formulations so they will remain stable with only the addition of an antioxidant.

What we are currently doing

Within the last few years we have removed the controversial paraben preservatives. We replaced them with methylisothiazolinone which was considered safe. In the last 12 months, concerns have been raised by dermatologists that methylisothiazolinone causes allergies in some people. We decided to replace this preservative with phenoxyethanol which is approved by the Soil Association for use in organic products. Some creams have already made the transition and others are in the testing pipeline.

When you change an ingredient you have to retest the product. This is called stability and challenge testing and can take a few months. If a product doesn't pass first time, the test has to be repeated and more months pass. So it can take quite some time for product changes to be made. 

What is phenoxyethanol?

Phenoxyethanol is an ether alcohol that is a mild preservative suitable for use on healthy skin, and in combination with other stronger preservatives is used in products intended for use on irritated skin. It is our main preservative. Phenoxyethanol is less likely to have side effects, such as allergic reactions, than other known preservatives (usually only experienced in large doses) and its use is approved by the Soil Association. www.cosmeticsdatabase.com scores phenoxyethanol as 4 (moderate) out of 10 where 10 is high risk, with a 67% data gap. Please remember that these ratings are for the undiluted, concentrated ingredient. In our cream formulations the total concentration of preservatives is less than 1% of the product. At this point in time, phenoxyethanol is considered the preservative with the lowest risk.

Why combination preservatives?

For products such as Starflower Cream (often used by people with eczema) and Tea Tree & Goldenseal Face and Skin Cream (often used by people with acne or fungal infections) we have historically used a preservative combination, at a maximum of 1%, combining phenoxyethanol with methylisothiazolinone, and the pH adjusters triethanolamine and citric acid. This was to ensure that the creams never become infected with bacteria that could be introduced to broken or irritated skin. We have to be very careful that in replacing the methylisothiazolinone with the gentler phenoxyethanol that the efficacy is not compromised. This takes time and we are in the middle of the development and testing process. Here is some more information about those ingredients:

What is methylisothiazolinone?

Methylisothiazolinone is a widely used preservative that is used as part of a combination preservative to avoid bacteria growing in an opened product that could potentially become a source of infection.

www.cosmeticsdatabase.org scores methylisothiazolinone at 6 (moderate) out of 10 where 10 is high risk with a 63% data gap. Please remember that these ratings are for the undiluted, concentrated product. When methylisothiazolinone is used on its own, the Cosmetic Ingredient Review (CIR) Expert Panel has limited the use to 100 ppm (0.01%). The Cosmetics Directive of the European Union (Annex VI, Part I) also authorises it for use at a maximum concentration of 0.01% (100 ppm). In our cream formulations the total concentration of preservatives is less than 1% of the product and of this methylisothiazolinone is used at or under the maximum of 0.01%.

What is triethanolamine?

Triethanolamine is an alkali surfactant used to adjust pH to neutral on the skin. The Cosmetic Ingredient Review (CIR) Expert Panel reviewed it and concluded that it is safe for use in cosmetic products intended for prolonged contact with the skin, in concentrations not exceeding 5%. Triethanolamine should also not be used in products containing N-nitrosating agents to prevent the formation of nitrosamines. Napiers does not use N-nitrosating agents.

www.cosmeticsdatabase.org scores triethanolamine at 6 (moderate) out of 10 where 10 is high risk, with a 64% data gap. Please remember that these ratings are for the undiluted, concentrated product. In our cream formulations the total concentration of triethanolamine is less than 1% of the product.

What is citric acid?

Citric acid is an alpha hydroxy acid used to adjust pH to neutral on the skin. Citric acid is naturally found in citric fruits and juices but is made commercially from sugar using bacteria and yeast.

www.cosmeticsdatabase.org scores citric acid at 2-3 (low) out of 10 where 10 is high risk, with a 72% data gap. Please remember that these ratings are for the undiluted, concentrated product. In our cream formulations the total concentration of citric acid is less than 1% of the product.

Why don't we discontinue lines?

When a preservative hits the news, some people think that we should immediately withdraw any cream containing it to be "on the safe side" and are angry to see a reputable company like ours still selling it. We take safety very, very seriously. All our products are tested on volunteers in the development stages and  many are used widely in our clinics. Where a product has been safely used for years and only a very small proportion of people react to it, we do not withdraw the product. This is because many people buy a favourite cream, such as Starflower Cream for dry, sensitive, itchy skin, depending on them year in, year out and would be hugely distressed if the product was withdrawn. 

Transparency

We are always transparent about our ingredients and methods. If they are not listed on the website it is purely because we have limited person-hours and will get there, but we will email you ingredients of anything missing.

Dispensing special creams

For people with very sensitive skin or allergies we also have very simple bases in our dispensaries and can make you up a special version of your preferred cream without an ingredient you may be allergic to. This will have a much shorter shelf life and in some instances may need to be kept in the fridge.

We are always here to help so do contact us if you have any questions or concerns.

© Napiers Herbals Ltd 2014 • Edinburgh and Glasgow • Herbalists and Medical Botanists since 1860
'
Offers Banner