The Effect Sunscreen Chemicals Have on Your Hormones

Recently, the Environmental Working Group released their latest report, investigating the hazards of sunscreen. Yes, you read right ‘HAZARDS’ … As we know sunscreens come in mineral and non-mineral formulations (as well as a combination of both). Mineral sunscreens are based around zinc oxide or titanium dioxide and provide superior protection when compared to non-mineral products, but can be toxic if they penetrate the skin. According to the Environmental Working Group, most studies show that these ingredients do not penetrate the skin or to reach the blood, but the research continues. Within non-mineral sunblocks some of the most common ingredients include octisalate (59% of products), oxybenzone (52%), and avobenzone (49%). Of these, it should be noted that oxybenzone can trigger allergic reactions, has potentially hormone disrupting effects and actually penetrates the skin in relatively large amounts. As an indicator of the prevalence of this substance, oxybenzone was found in over half of the 814 beach / sport sunscreens reviewed by EWG’s report.

Wait, there’s more …

A recent European study also detected traces of four common sunscreen chemicals in mothers’ milk, implying the potential for exposure to not only newborns but developing fetuses as well (Schlumpf et al., 2008).

The table below summarises sunscreens with the highest concern for human exposure and toxicity

The Environmental Working Group note that no ingredient is without concern and that their rating system took into account both the range of concerns and the differences in the weight of the evidence for each ingredient.

The chemicals found in sunscreens with lowest concern for human exposure were:

• Avobenzone
• Mexoryl SX
• Octisalate
• Tinosorb M
• Tinosorb S

For those of you who may be interested to read the complete report, it can be easily found at - 

http://breakingnews.ewg.org/2012sunscreen/ 

Reference:

Schlumpf, M., Kypke, K., Vokt, C., Birchlers, M., Durrer, S., Faass, O., et al. (2008). Endocrine active uv filters: Developmental toxicity and exposure through breast milk, Chimia, 62, 1-7.