Although the vast majority of the 2,000 ingredients used to make fragrances are completely harmless, around 24 commonly used substances are known allergens.

And these could cause a small proportion of eczema sufferers, or those with sensitive skin, to break out in a rash when they use the perfume.

However, at the moment there is no obligation for the manufacturers to label which substances are included in the mixture, so consumers do not know which perfumes could cause them problems.

Dr Susan Parker: 'companies should be more open'

Lucy Davis has to avoid perfumes because she cannot tell which will irritate her skin, and which will not.

"I tend not to use fragrances at all because I know my skin is sensitive - but I don't know what it is sensitive to."

Consultant dermatologist Dr Susan Parker said that it was time for the companies to be more open.

She said: "There are 24 ingredients that the EEC are currently looking at as being the main sensitizers, and if those were labelled, that's not an unreasonable request."

New labelling arrangements

The trade association for the industry, the Cosmetic, Toiletry and Perfumery Association, said it was trying to arrange clearer labelling with the EC.

A spokesman said: "Consumers who are allergic to perfume should avoid products which contain parfum. The industry is currently discussing ways in which labelling of specific fragrance ingredients could be agreed and introduced."

More than 800 perfumes have been launched in the last decade, and fragrance producers are notoriously secretive about the formulas used to produce each distinctive smell.

If the fragrances were labelled properly, consumers could then take allergic 'patch tests' to work out which ingredients were not tolerated.

Small amounts of a number of different ingredients are spread on different small areas of skin, and examined later for any signs of allergic response, such as reddening, or rash.