'Shop-bought sunscreens are made to meet certain standards  under EU law they have to be safe to use and are tested to check they give the protection claimed on the bottle.'

London - Organic enthusiasts are risking contracting skin cancer by using DIY sunscreen, doctors warn.

In a worrying trend on the internet, alternative health bloggers are advising people to use coconut oil and beeswax to protect their skin because shop-bought sunscreen has “toxic ingredients”.

Some advocates claim that ingredients such as carrot seed oil and red raspberry seed oil have a sun-protecting SPF of up to 50 – a claim dismissed as “absolute nonsense” by medical experts.

Sarah Williams, senior health information officer at Cancer Research UK, said: “Shop-bought sunscreens are made to meet certain standards – under EU law they have to be safe to use and are tested to check they give the protection claimed on the bottle.

“With a homemade sunscreen, there’s no way of knowing how much protection, if any, you get.”

Dr David Fenton, a consultant dermatologist in London, said that cancer is a real risk if people expose themselves to the sun without proven protection.

“We have no idea how safe these products are if they are produced in the kitchen sink,” he said.

“Obviously anyone who tries to mix their own sun protection is really putting themselves are risk. Anyone who relies on something like this is putting themselves at real risk of a melanoma.”

Cosmetics firms have to carry out substantial testing before they can assign an SPF value to a product.

According to strict industry rules, each active ingredient has to be shown to remain stable when it mixes with other ingredients, not degrade over time, and have a consistent level throughout the cream.

Emma Meredith, director of science at the Cosmetic, Toiletry and Perfumery Association, said: “The idea of people making their own sun protection products is of great concern to us.

“It is very important to stress that effective sun protection is vital for health and using sunscreens is one part of a sun safe regime. ‘There are no short-cuts to making a sun protection product and there should be no home-made options.”

Dr Mervyn Patterson, who runs cosmetic clinics in London and southern England, said: “Making and using these home brew products is really taking your chances.

“It is like Russian roulette - you don’t really know what the ingredients do, there is no way to measure their SPF, it is just absolute nonsense and really quite dangerous.”

Other experts said that people who really are worried about the chemicals added into commercial sun screens should simply cover up or stay out of the sun.

Matthew Gass of the British Association of Dermatologists said: “When it comes to sun safety it is important to understand the level of protection that you are being afforded by the products you use.

“When making your own sunscreens at home it is not possible to accurately test their effectiveness, and you run the risk of doing damage to your skin in both the short and long term.

“Industry developed sunscreens are tested for safety and efficacy, but there are alternative means of sun protection. Make sure you protect the skin with clothing, including a hat, T-shirt and glasses.

“Spend time in the shade between 11am-3pm when the sun is at its most powerful, and make sure you keep babies and young children out of direct sunlight.” - Daily Mail