Skin deep?

We regularly avoid food additives with strange- sounding names, spurn salt, and shun saturated fats in the quest for a healthy lifestyle. Ingredient labels on food are scrutinised as never before for signs of unwanted preservatives, flavourings, and colourants. And yet, after a healthy breakfast of wholegrain, non-GM cereals with nothing added, millions will make straight for the bathroom and splash, rub and spray cocktails of unknown chemicals on to their skin and hair.

While makers of baked beans and ketchup are required to list every one of their ingredients, cosmetic producers are not. Indeed, in some cases, the list of ingredients would be so big, that it would be physically impossible to reveal all. Cosmetics generally consist of an extensive combination of chemicals, with more than 3,000 available to makers in Europe. Critics maintain that little is known about the health impacts of many of them, particularly the effects of prolonged use.

Chemicals in hairsprays, perfumes and loose powders can be inhaled, irritating the lungs, while lipstick is inadvertently licked and swallowed. Chemicals in all kinds of dyes, cosmetics and fragrances enter the body through the skin surprisingly easily – that is why rub-on and spray-on pain-relievers work, and it's also the way that an increasing variety of drugs are being delivered. Kim Erikson, author of Drop-dead Gorgeous – Protecting Yourself from the Hidden Dangers of Cosmetics, says that the advantages of the synthetic ingredients in cosmetics are that they are inexpensive, stable, and have a long shelf-life: "Manufacturers love them, but although the majority of products appear safe in the short run, the results from long-term use could be unhealthy."

Researchers at the Université Louis Pasteur, Strasbourg, say that one of the problems facing doctors trying to find the source of any problems is that new compounds are constantly being used as the industry makes refinements to its products. Another problem is the impracticality of carrying out long-term observations on the effects of chemicals. Some researchers and consumer groups fear that because the chemicals are used regularly, over time a cumulative build-up may result in as-yet-unknown effects on health.

Meanwhile, in the short term, skin allergies are a problem for an increasing number of consumers, who may be particularly sensitive to fragrances. One notable coup for the EU Scientific Committee on Cosmetic and Non-food Products is that it has pioneered a requirement for fragrance-makers to list any of 26 different ingredients that can cause reactions. Until now, the ingredients of fragrances have been allowed to bask in anonymity, leaving the consumer to find out the hard away whether or not the allergen to which they are sensitive is included. But that requirement, which should come into force within two years, applies only to the listed ingredients known to cause problems in some people.

So toxic are some substances in use that consumers can react to the tiniest of amounts: "Oak moss is widely used and is a very important cause of reactions," says Dr Ian White, consultant dermatologist at St John's Institute of Dermatology, Guy's and St Thomas' Hospital in London. "Until very recently we did not know that it was chloratranol in the moss that was so fantastically potent." As a result of this discovery about oak moss, whose role is to help the fragrance stay longer on the skin, it is expected that pressure will be exerted to restrict its use in cosmetic products.

Some researchers and consumer groups believe that, of all of the cosmetics on the market, some hair dyes pose the biggest potential risk. This week, the EU's Scientific Committee on Cosmetic and Non-food Products will conclude that the safety of 57 chemicals used in hair dyes cannot be guaranteed. As that is almost half the total number of chemicals most widely used in the industry, the chances are that many consumers may well have been exposed to one or more of these compounds. The committee's decision, which has implications for the four out of 10 women, and an unknown amount of men, who use dyes, comes in the wake of research linking dyes to a range of health problems, including cancer, foetal problems, allergies and skin problems. Links have also been made with arthritis and lupus.

Doctors say that although any major epidemiological investigation would take years to complete, some action is needed in the meantime: "There is a need for measures to be introduced to protect the consumer in the interim. The European cosmetic industry uses a considerable number of permanent hair dyes, and the safety of many of these has not yet been assessed by public authorities," states the EU Scientific Committee's report. The concerns centre mostly on permanent dyes, including oxidative hair products, which make up the biggest segment of the growing market. These products are resistant to fading as a result of shampooing, but recolouring is needed every month to six weeks because of new hair growth, and as a result, chemicals can be in contact with the scalp for up to 45 minutes at a time.

Research at the University of Southern California found that women who used permanent hair dyes at least once a month were up to three times more likely to develop bladder cancer. An American Cancer Society study looking at other types of cancer found that using black dye for more than 10 years was associated with a small increase in risk of death from multiple myeloma and non-Hodgkin's lymphoma. Fears have also been raised about the risk of arthritis and damage to unborn children linked to permanent hair dyes. Research by the US Food and Drug Administration has found, too, that almost one in four people had suffered an allergic reaction to personal-care products, including hair dyes.

The EU Scientific Committee on Cosmetic and Non-food Products, which met yesterday in Brussels, will later this week publish its report on hair-dye chemicals. "The problem with hair dyes is that the safety profiles on the substances that are being used are not complete, or are inadequate, or do not conform to present standards. There are questions about the safety of individual chemical substances by themselves, and also about what happens when they are mixed together to form the products to which the consumer is exposed," says Dr White, who also heads the committee.

"Our object is to make it a safer world for consumers. Problems have been raised by member countries about each of the 47 hair-dye chemicals that we consulted them on. We are going to say this week that not one of the safety dossiers on them, provided by the industry, conforms to current guidelines. In other words, the industry has failed to prove that they are safe," says Dr White.

But why do so many of us use these products so liberally without even knowing what is in them? "It is a social thing. It's about appearances, but it is very important to people. It's not uncommon, for example, to hear people say that they would rather be dead than grey. Our job is to protect them as much as we can, and that is what we will be doing when we publish our report."

With much more research to do, and increasing evidence of links with ill health, the hope is that people who do use hair dyes and other cosmetics don't live to regret it.