Why are Preservatives Necessary in Cosmetics?

Science 101: Why are Preservatives Necessary in Cosmetics?

In order to make commercial cosmetic products, ie. those products that we use on our skin and hair, those products you encounter on a day to day basis, a preservative is necessary. 

What is a preservative?

A preservative can be natural or synthetic and is added to food products, pharmaceuticals or cosmetics to prevent spoilage, whether from microbial growth or undesirable chemical changes.(Source). Typically they add nothing to the actual effectiveness of the product but they prevent the growth of microbes which are hazardous to health and cause disease.

Some examples of common preservatives you will see in your every day products are parabens, formaldahyde donors, phenol derivatives, quats, alcohol, organic acids and many others. However in more recent years,  consumers would like their hair and skin care products to be 'green' and 'natural' and are shying away from parabens and many of the traditional preservatives.

Why do we need preservatives?

Cosmetics can be contaminated very easily by microbes, which can cause infection and be damaging to our health. Without a preservative, cosmetics would have to be stored at a low temperature and require fresh, sterile applicators for every use, which means no fingers ladies! Gram negative, Gram positive, yeasts, and moulds have all been found growing in different types of cosmetics. (Source)

What is a Paraben?

Parabens are a class of chemicals used as preservatives in cosmetics. they are mainly used because of their bacterial and fungicidal properties and are particulary popular because of their high efficacy and low cost. They are produced by the esterification of para-hydroybenzoic acid with an appropriate alcohol.

Parabens are amongst the most effective, broad spectrum preservatives on the market and have been used and tested over several years. However several cosmetic brands have been released as paraben free due to controversy from a Danish study.

Are these preservative dangerous?

A danish study showed that when paraben cream was applied to the backs of healthy male volunteers that the chemical could be measured in their blood after a matter of hours. Parabens are known to be absorbed, metabolised and excreted quite quickly so this would make sense.

"Preservatives are designed to kill cells. That is why they are effective. Unfortunately, that is also why they are potentially hazardous. They do not easily discriminate between good human cells and bad microbial cells but ultimately, the risk from using preservatives is significantly lower than that of using unpreserved cosmetics" (O'Lenick,, 2010).

So far there has been no link to the possible carcinogenicity of parabens and their continuous use, hence the ongoing scientific debate. These ingredients have also been used for years with lots of supporting safety data and they are still legal for use in the EU. 

In recent years Phenoxyethanol has taken the place of parabens in many cosmetic lines. In the EU, this preservative can only be used at levels below 1%.

How is this regulated?

Preservatives are regulated by the EU Cosmetic Regulations and in cases where there may be cause for concern that people may be allergic to an ingredient, an ingredient may be banned (as has been the case for many fragrances) or a maximum permitted limit is put in place. It is because of the EU Cosmetic Regulations that products made here in the UK most go through rigorous tests before they are placed on the market anywhere in the EU and their ingredients and amounts declared.

In the EU if a cosmetic preservative is not listed in the Cosmetic Directive 76/768/EEC, you cannot use it unless you go through the processes to have it approved, which can be very costly and complicated.

Once a preservative has been established for a formulation, the product must go through a Preservative Efficacy Test to establish how long the product will be viable before it is compromised by microbes. 

You can see that preservatives are therefore necessary for the safety of commercial cosmetic products.

Is there such a thing as a 'Preservative Free' product?

Truly preservative free products only last for a very short time, meaning that you can only buy them in very small quantities. Small companies are often able to offer products with 'natural' preservatives but often these will have a short shelf life and many of the preservatives will only combat the growth of a small number of microbes. 

The alternative to buying green preservative free products is to make your own.

Some preservatives you may be able to use in those products you make yourself at home:

Neem Oil - Used in India since the time of Sanskrit, Neem has really proved its worth and is one of the most powerful oils on the market today. As well as being anti-fungal and anti-bacterial, it is also an anti-protozoan!

Rosemary Extract - We’ve previously told you about the wonders of rosemary oil for your hair, but who knew it could work miracles for your skin too? Rosemary extract works against aging processes such as dark spots, thickening and wrinkling, as well as being anti-bacterial and anti-microbial.

Honey - Made by busy bees, honey is known for being highly stable against microbial growth because of it’s low moisture content and water activity, low pH and anti-microbial constituents.

Bee Propolis - More from our buzzy friends, propolis is a mixture of beeswax and resins collected by the honeybee from plants. Used by bees to protect the hive, offering both anti-bacterial and anti-fungal attributes, the Greeks and Romans would use it to heal skin abscesses!

Embrace Your Inner AfroDeity
Leilu






Resources:

Anthony J. O'Lenick, Jr., (2010) Siltech; Cosmetics and Toiletries; Comparatively Speaking: Cosmetic Preservatives; http://www.cosmeticsandtoiletries.com/formulating/ingredient/preservatives/91617569.html?page=3
http://chemistscorner.com/alternative-cosmetic-preservatives-what-are-your-options/
http://chemistscorner.com/how-to-prevent-contamination-in-cosmetic-products/