Sort out which are myths or scares and put what you read into perspective

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- Preservatives

- Hair dyes

- Fragrance (Parfum)

- Artificial nail systems


What is an allergy?Person scratching their arm

‘Allergy’ is a term that is often misused to describe all kinds of adverse reactions. There are two main types of adverse reactions that may be experienced: irritant reactions and allergic reactions.  In fact there’s a big difference between being irritated by a substance and being allergic to it.

Irritant reactions are the most common adverse reaction and should not be confused with allergic reactions. An irritant type of reaction occurs rapidly following use of a product. Redness of the skin, sometimes with an itch, is characteristic of an irritant effect. This clears up rapidly after ceasing to use the product that is causing the problem.

Allergic reactions are excessive reactions by our bodies to substances in our environment that are harmless to the majority. Unlike irritant reactions, allergic reactions involve the body’s immune system. A person who is allergic to a substance may be sensitised to it for the rest of their life yet most people would never become allergic to that same substance. Everyone is different – what you will become allergic to is determined by your genes.  Some people may never develop an allergy.

To find out more about allergy and how it works, click on the image below to look at the full infographic:

Infographic thumbnail

How does allergy work?

There are two main types of allergy:

  • Immediate:Immediate and delayed reactions an allergic reaction that occurs suddenly, generally a few minutes after exposure to the allergen. Common examples are hay fever triggered by pollen or allergic asthma triggered by animal hair.
  • Delayed:
    an allergic reaction that does not show until some time, usually 24 to 72 hours, after contact with the allergen. An example is ‘allergic delayed contact dermatitis’ triggered by skin contact with the allergen and producing a local reaction at or near the area of contact. If further contact with the allergen is avoided, there will be no further reaction and the skin heals.


Can cosmetics cause allergies?

"People can even be allergic to commonly used products. It’s not that ingredients in these are unsafe – it’s the way the body reacts to them can differ from person to person."
Dr Chris Flower, Director-General of CTPA and a Chartered Biologist & Toxicologist

Almost any substance, natural or man-made, has the potential to produce an allergic reaction in someone, somewhere; the body does not differentiate whether something is natural or synthetic - it is the properties of the substance itself and not its origin that is key. As with some foods, you may not know you are sensitive to a cosmetic ingredient until you try out a product and have an adverse reaction. However, where a higher risk of allergy has been identified, such as with some hair dyes, the product will always carry a warning label and users will be advised to carry out an allergy alert test before applying the product in full.

Cosmetic products are subject to strict European safety rules to ensure that they don’t pose a health risk. Safety assessments include allergy safety, which greatly minimises the risk of products causing adverse reactions.

"The process of determining the safety and composition of a product is rigorous and great care is taken to constantly re-assess the science behind it. This means a team of scientists will be involved ensuring the latest scientific knowledge and safety evaluation techniques are used. It can take many years to bring a product to market."
Dr Emma Meredith, Director of Science at CTPA and a Pharmacist

Why are ingredients known to cause allergies used in cosmetics?

Substances known to cause widespread allergic reactions are not used in cosmetics but each person is different and we might find we are allergic to substances that others use or consume without any problems. For example, many people eat peanuts and yet some cannot, and whilst pollen makes summer miserable for hay fever sufferers the majority have no such problems.

It is not possible to avoid all substances in cosmetics that might cause a rare allergic reaction in someone any more than we could avoid all foods to which someone might be allergic (such a list would include nuts, eggs, wheat and flour, and so all biscuits, cakes etc., shellfish, many fruits and many common vegetables).

It is important to always check the ingredients list of the cosmetic product you intend to buy or use to make sure it does not contain any ingredients to which you are allergic.

PreservativesCartoon of bacteria cell
Of all classes of cosmetic ingredients, preservatives are more likely to cause allergies than the rest. However, preservation is essential for cosmetic safety and quality, and avoiding preservatives completely is not possible.

There is a small pool of effective preservatives that are allowed to be used in cosmetics. They are needed to keep products bug-free, but unfortunately some people may be allergic to one or more of them. Only a few have the rare quality of being able to work across a variety of products in order to keep them safe and microorganism-free without changing the formulation which creates the look, feel and smell.

preservative film iconView a short film clip to see why preservatives are so important.

The European Commission infographic emphasises the importance of preservatives for cosmetic products.  Preservatives are used in cosmetic products all around the world and the International Cooperation on Cosmetics Regulation (ICCR) has also produced an infographic to highlight their importance.

Hair dyesHair colorant pack
Permanent and oxidative hair dyes are used because they are the best way to achieve permanent hair colour and the only way of colouring grey hair. The number of reactions to these hair dyes is very low and they are safe to use when instructions are followed, including an Allergy Alert Test.

One hair dye, para-phenylenediamine (PPD), is safely used in hair colorant products.  However, you may see PPD being used (illegally) in so-called “black henna” temporary tattoos.  If applied directly to the skin in a temporary tattoo, PPD can cause quite severe reactions. Consequently, this use of PPD is prohibited. Find out more about the illegal use of PPD and how to avoid it.

Fragrance (Parfum)Fragrance bottle
Although rare, reactions to fragrances sometimes occur. Consumers diagnosed as allergic to certain fragrance ingredients should avoid all fragrance, which is shown on the list of ingredients by the word "parfum", unless they have checked with the manufacturer of a particular fragrance whether or not the problem ingredient is present in the product. However, 26 fragrance ingredients known to cause a higher incidence of allergy will be listed individually to help consumers make an informed choice.

Find out more about fragrance allergies and fragrance-free cosmetic products

Artifical Nail Systems
Many artificial ‘build-up’ nails are based on substances called acrylics or acrylates.   

HEMA and di-HEMA trimethylhexyl dicarbamate are methacrylate chemicals which are active components of artificial nail systems.  When exposed to UV-light by means of a UV or LED lamp, the nail is ‘cured’, meaning that HEMA and di-HEMA polymerise to form the hard, durable surface of the artificial nail.

In a small number of cases, the uncured (unreacted) methacrylate monomers can produce an allergic reaction if they come into contact with the skin. 

Dermatologists are seeing more patients with allergies to UV-cured artificial nails. 

Therefore, whether visiting a nail salon or carrying out a home manicure  it is extremely important that all information labelled on-pack and the directions for use are read and followed carefully every time, to ensure that any uncured HEMA and di-HEMA are removed following the curing process.

The nail system should only be used with the corresponding LED or UV lamp which is specified by the manufacturer.  If the incorrect lamp and nail system are used together, the nail system may not be fully cured, which can lead to more uncured methacrylate monomers remaining on the nail surface and a possible increased risk of allergy.

This is especially important for home use, to make sure the product is used and applied as intended and only on the nail bed.

If you have any concerns about your nails and how to care for them, do speak with your nail salon professional who will be able to advise you on how often you should have your artificial nails applied and how to keep your nails in best condition.

Acrylates have a wide range of applications, including in certain medical and dental procedures.  If an individual develops an allergy to methacrylate chemicals, through exposure to the chemicals in any of these applications, this can have implications for any future dental and medical procedures.

Ingredient labellingIngredient Booklet Cover Thumbnail

All cosmetic products sold in the European Union (EU) must display a complete ingredients list. In whatever European country you buy your cosmetic product, the ingredient names will be the same. 

This helps users to identify products with ingredients to which they know they are sensitive. Ingredient names must, by law, comply with European requirements and use the International Nomenclature of Cosmetic Ingredients, known as INCI.

The CTPA has produced an ingredient labelling help note for dermatologists.  The booklet is available to download as a pdf file.

What does ‘hypoallergenic’ mean?

‘Hypo-‘ means ‘less than’ or ‘decreased’ so, when used to describe cosmetics, the term hypoallergenic means ‘reduced potential to cause allergic reactions’. Manufacturers will have made special efforts in the selection of ingredients and by product testing to reduce further the already low incidence of adverse reactions to cosmetic products. These products may still contain fragrance, identified in the ingredients list as ‘parfum’.

What should I do if I have an allergic reaction?

In practice, few reactions are true allergies. Most turn out to be irritations and indicate that the particular product and your skin are not compatible. Such reactions will be temporary and mild, usually with a little redness, itching or other slight discomfort.

However, you should always contact the manufacturer (careline or helpline numbers are provided on the pack) so that they are aware that someone has experienced a reaction to their product. They will then be able to advise you further on what action to take next. If the reaction persists or recurs or you are otherwise concerned you should consult your GP.

Your GP may refer you to a skin specialist, such as a dermatologist. A dermatologist will be able to diagnose the cause of the problem, advise on how to treat it and help you to avoid further reactions in future. In particular, they will advise on the ingredient(s) that you should avoid.Consumer Guide

Manufacturers of cosmetic products want consumers to enjoy using their products.  However companies want to know if someone has a reaction to their product.  A guide has been produced to help explain what to do in such an instance and why it is important to inform the cosmetic product manufacturer.

Where can I find out more?

Download our allergy factsheetAllergy Factsheet

To find out more about allergies and preservativesview information from the European Cosmetics Trade Association, Cosmetics Europe.

To find out more about dermatologists and cosmetic allergy visit the British Association of Dermatologists.

If you want to find out about different types of ingredients in your products, visit what's in my cosmetic?