Oxybenzone (Benzophenone-3)

“There are many things that we know we know. There are things that we know we don’t know. But there are also things that we don’t know that we don’t know. And this last category grows each year.” This statement applies to many things in life, but also especially to do with the safety of cosmetics. How can we be sure and guarantee that ingredients in cosmetics are safe if we don’t ask ourselves what effect daily use has, on children, pregnant women and from long term use. Safety is a relative term that has been demonstrated many times throughout history. Remember a certain type of phthalates which were once safe but are now no longer permitted to be used in cosmetics. “At that time we didn’t know that we didn’t know it, but now we do know it”. Therefore today more information about Oxybenzone.

When are cosmetics “safe”?

Safety is a difficult subject. When I advise people about cosmetics I don’t want to make them panic but I do think they should be aware when deciding on whether to use a cosmetic product or not. And how can you consciously decide if you simply don’t know…One thing is absolutely clear: the fact that beauty products are tested doesn’t guarantee that their long term use is safe. Cosmetic products are not medicines, and it is relatively easy to bring cosmetic products/ingredients onto the market. When I’m giving advice about cosmetic products it is based upon research from so-called peer review journals. I try and explain whether the investigations are independent and properly carried out. Not always easy…And no matter how scientific the approach is, after reading and assessing all the information, my advice is given with a personal touch. If I can recommend a product I must firstly ask myself: would I be happy to use this on my own skin and that of my childrens? For products containing the ingredient oxybenzone (benzophenone-3) on the basis of what I know the answer is : no. But perhaps your opinion will change after reading this piece. But that is, at least, your conscious decision!

What does Oxybenzone actually do?

Oxybenzone is a common ingredient in sun creams. It’s use is approved, but for some years this substance has come under discussion. And that is not so strange if you look at the results gained from several independent scientific investigations. Oxybenzone is used in different cosmetic products. A lot, of course as a sun filter in sun cream products. It protects against UVB radiation and to some extent UVA radiation. It is not the strongest filter and so has to be combined with other filters. It can add strength and stability to the other filters. It is used, alongside this, in other cosmetic products such as moisturisers, lip balsam, body lotion, nail polish and shampoo. Its purpose, among other things, is to strengthen and stabilize the smell and colour in these products.

Irritation

Together with perfume and preservatives, sun cream filters are one of the most common causes of skincare allergies. In particular the chemical filters can cause skin irritations. Oxybenzone is a forerunner in this area.

Absorption by the body

Absorption of oxybenzone in the body is, in my opinion, one of the most important reasons for choosing an alternative filter. It is undoubtedly clear that oxybenzone is very readily absorbed into the skin and subsequently gets into the circulation finally ending up in the urine. It has even been found in breast milk. Although several chemical filters can penetrate through the skin, the uptake of oxybenzone is exceptionally high. In 2008 a study carried out revealed that 96.8% of the 2,517 urine samples contained oxybenzone. The concentration was associated with the use of cosmetics. An estimated 10% of the amount applied penetrates through the skin. Moreover it seems that oxybenzone can build up in the body. In an investigation carried out 25 people applied sun cream, containing 4% oxybenzone, twice a day over 5 consecutive days. It was clear to see that after 3 to 5 days after the last application there was still oxybenzone found in the urine samples. Children have more difficulty breaking oxybenzone down than adults as the enzymes used in the breakdown are less effective in children.

Hormonal activity

Oxybenzone has a hormonal activity. That is to say; this chemical can attach itself to a hormone receptor and imitate the action of a hormone. That has been established with the aid of a test tube and animal testing. The extent of the harm caused is not known, the hormone activity is low. Yet we don’t really know the effects of long term use and use by groups at risk such as pregnant women, breast feeding mothers and women in a high risk category for breast cancer.

Toxicity

A study carried out where rats were given Oxybenzone twice daily for four weeks, showed that it was not toxic for rats. This dosage is many times higher in rats than in humans, so the chance of this in humans is very small.

Cell damage

Oxybenzone can form free radicals. In sunlight oxybenzone is readily oxidised to form oxybenzone semiquinone, a powerful substance which attacks our anti-oxidants. This anti-oxidant system (our army) protects us against cell damage and the development of cancer. Having said that it has never been proved that Oxybenzone increases the risk of people getting cancer!

To smear or not?

As I pointed out in my last blog it is far safer to smear in a product containing Oxybenzone than to sit unprotected in the sun. I’ll repeat it once more: regular protection against the sun can stop around 80% of skin cancer cases from occurring. And even getting sunburnt once can substantially increase the chances of getting skin cancer. So I advise you to consciously look at the ingredients in your sun cream and be sure! I promise a list of suitable products very soon….

Regards and have a good weekend,

Jetske.

(Dr. Jetske Ultee-Research Physician Cosmetic Dermatology)

You can listen to my interview with Dutch radio station Radio 1 about oxybenzone here. You can also read:
‘Help with Choosing a Sun Cream’,
‘Acne Improves Due to the Aun?; A Myth!’,
‘Do Anti-Oxidants Also Really Work in a Cream?‘,
‘what to do’ if you’re sunburnt: ‘You’re So Red!‘ and
‘The Recipe for Beautiful Skin‘.