Cosmetics and cancer

Cosmetics are made up of a variety of different chemicals. And many of the rumours about cosmetics and cancer are based on common misunderstandings about these chemicals. The claims assume that if a chemical is linked to the development of cancer in cells in a lab experiment, it will also cause cancer in humans. But this is misleading for a number of reasons.

Human beings are much more complex than cells in a lab dish. 

Many concerns arise from studies that test the effects of chemicals on cells in lab experiments. But applying a high dose of a chemical directly to cells in a dish is very different to applying a cosmetic to our bodies. For example, our skin forms a formidable barrier and prevents many chemicals from being absorbed. And when chemicals do get inside our bodies, they tend to be broken down by our body and safely removed. So something which is harmful to cells or even animals may not cause health problems in humans.

The dose may be different. 

At very high doses, many common chemicals are dangerous to our health. For example, taking a standard dose of ibuprofen will help to reduce inflammation but taking too much may cause stomach ulcers. High doses of some chemicals contained in cosmetics may cause cells to turn cancerous in a laboratory experiment. But legislation means that cosmetics for sale in the UK must be safe – normal use of these cosmetics must not cause harm to humans.

Natural chemicals are not necessarily better for you than man-made ones. 

The rumours about cosmetics and cancers also often imply that synthetic or man-made chemicals are worse for you than natural ones. This is not scientifically meaningful because natural and man-made chemicals are not fundamentally different. Many natural chemicals can cause cancer so avoiding synthetic chemicals will not have a large impact on your cancer risk.

The charity Sense about Science has produced an excellent document about chemicals and our lifestyle. And this also highlights the need to look at alarming stories about chemicals in context:

• The concentration of a chemical is important. Some chemicals are detected in the body at levels of ‘parts per billion’ – this equates to one grain of sugar in an Olympic sized swimming pool.
• Our bodies are able to process and remove harmful substances.
• And even if a chemical is present in our body, that doesn’t mean it is doing any harm. Our bodies contain traces of many substances that we are in contact with. These include both natural and synthetic substances, and some are beneficial and some are harmful at certain levels.

There are very tight regulations in the EU and the UK about cosmetics. Manufacturers must ensure that their cosmetic products are safe before they can be sold. The EU has produced a list of banned substances that are not allowed to be used. And other chemicals are only allowed in cosmetics subject to special restrictions. For example, they may only be present in limited amounts or may only be used in rinse-off products. This applies to both natural and synthetic chemicals.

Deodorants and parabens

Many scare stories about cosmetics relate to chemicals called parabens. Many of these stories focus on deodorants, and you can find out more on our deodorants page. Some recent media reports suggest that parabens found in breast tissue come from other cosmetic products rather than deodorants. However, there is no good scientific evidence to suggest that parabens from any cosmetics can cause cancer in people, nor that the levels of parabens found in these tissues are harmful.

Lipstick

Another persistent hoax claims that lipsticks contain lead and therefore cause cancer. This is not true and you can find out more on our CancerHelp UK website.

Moisturisers

Rumours that moisturisers could cause skin cancer also make the rounds occasionally. Most recently, such a claim was made based on a laboratory study which found that moisturizing creams could increase the risk of skin cancer in mice that were already exposed to high doses of ultraviolet (UV) radiation, mimicking the effect of heavy sun exposure.

But that is a long way from saying that this also applies to humans. Our Science Update blog took a thorough look at what the scientists actually found and what it means for humans.

Hair dyes

Hair dyes have been involved in cancer scares too. But there is no clear scientific evidence to show that hair dyes could cause cancer. See our take on the evidence on our hair dyes cancer controversy page.