The “burning” question regarding the ingredients: Oxybenzone

The “burning” question regarding the ingredients: Oxybenzone

Based on their ingredients, there are two different types of sunscreens available in Canada: mineral and non-mineral sunscreens.

Although not normally labeled as such, it is very easy to tell the differences between mineral and non-mineral sunscreens by simply by looking at the ingredients listed on sunscreen products.

Sunscreens that use a varying combination of chemicals to ‘absorb’ the UV radiation, such as oxybenzone and avobenzone are non-mineral sunscreens while sunscreen that contain minerals, such as titanium dioxide or zinc oxide, to “block” UV radiation are, you guessed it, mineral based sunscreens. 

As you can see, these two types of ingredients provide UV protection in two different ways – one by absorption (chemical) and one by reflection (mineral).

Most of the criticisms regarding sunscreen composition are directed towards its chemical ingredients; the most problematic being Oxybenzone.

Properly known as 2-hydroxy-4-methoxybenzophenone or benzophenone-3, oxybenzone is one of the main ingredients in non-mineral sunscreens as it is relied upon to provide UVB protection, by absorbing UVB radiation, and UVA protection by acting as a chemical stabilizer for avobenzone, an effective but less chemically stable UVA agent.

Not only has oxybenzone been shown to be easily absorbed through the skin and into the blood stream from sunscreen application, it is also a known hormonal disruptor – a classification of chemicals that can mimic or disrupt the bodies natural production of hormones which may lead to several health consequences including some cancers (e.g. bisphenol-A and breast cancer). However, long-term low environmental exposure to oxybenzone has yet to be conclusively linked to any negative health effects.

We simply do not know if there are any long term health effects from exposure to oxybenzone from sunscreens especially in specific segments of the population including children and pregnant women who may be more vulnerable to hormonal disrupting chemicals.

Should we be concerned?

According to the precautionary principle, it may be prudent to avoid oxybenzone based on the lack of scientific evidence that it poses any long-term harm especially to those who may be more vulnerable to hormonal disrupting agents.

With that being said, we should not be paranoid either. Lack of evidence does not necessarily mean that oxybenzone poses any significant harm. For that reason, the Canadian Cancer Society states:

Like other Canadian and international organizations that make sure laws are enforced to protect health and the environment (regulatory agencies), the Society is not concerned at this time about oxybenzone in sunscreen. The research on oxybenzone is limited, and so far no animal or human studies suggest this chemical might cause cancer
(http://bit.ly/dqgNog)


  
Based on this information, it is up to you whether you want to use sunscreen that contains oxybenzone. There are alternatives available including mineral based sunscreens (zinc oxide and titanium dioxide) that you may want to use instead but, as we will see in the next blog entry, these types of sunscreens have their own issues. 

We all know that the primary way to stay safe from the harmful effects of the sun is by staying in the shade, avoiding the sun during peak hours or remaining covered while outdoors.

Even though the long term of being exposed to the ingredients in sunscreen is still not known, it remains a great secondary measure of sun protection. If we are ever in a situation where the only available protection is from a chemical based sunscreen that contains oxybenzone, rationale says “use it”.

The science is clear what happens when you are exposed to the sun without protection.

Next up on Be “Sun” Savvy
•    Issues regarding mineral based sunscreen
•    Issues regarding retinyl palmitate (vitamin a) in sunscreen and issues regarding sunscreen sprays
•    Proper sunscreen etiquette
•    Conclusion

Sources of Information
Canadian Cancer Society. (March, 2010). Sunscreen and cancer. Accessed on June 18th,
2010 at http://bit.ly/dqgNog


Environmental Working Group. (2010). EWG’s 2010 sunscreen guide. Accessed on June
15th, 2010 at http://www.ewg.org/2010sunscreen/


Gavura, Scott. (June, 2010). The great sunscreen cover up. Science-Based Medicine.
Accessed on June 18th, 2010 at http://www.sciencebasedmedicine.org/?p=5541