Sunscreen Filters

SUNSCREEN FILTER INGREDIENTS: What should you look for?

Physical vs chemical sunscreen filters:

Sunscreens contain chemical or physical filters to protect skin from the sun’s harmful ultraviolet (UV) rays. Chemical filters like avobenzone, oxybenzone and octinoxate absorb and deactivate UV rays changing the light energy to heat. Physical filters like zinc oxide and titanium dioxide sit on the skin’s surface. Light is largely reflected and scattered away from the skin.

Concerns with chemical sunscreen filters:

Most chemical sunscreen filters are made up of small particles that are absorbed into the skin. Examples include oxybenzone, octinoxate, homosalate, octisalate and octocrylene. By contrast, physical sunscreen ingredients like zinc oxide and titanium dioxide contain large particles that sit on the skin. Dozens of studies in the last decade have examined the potential health hazards of sunscreen chemicals, including skin irritation or allergy, hormone disruption and skin damage that occurs when sunlight interacts with sunscreen chemicals. Many sunscreen chemicals are known or suspected hormone disruptors, allergens and carcinogens.

The Environmental Working Group (EWG) is an American environmental organization that specializes in research and advocacy in areas including toxic chemicals. They are a non-profit, non-partisan organization dedicated to protecting human health and the environment (www.ewg.org). The EWG rates products and ingredients according to their safety. A hazard score from 1-10 reflects known and suspected hazards of ingredients: 1-2 = low hazard, 3-6 = moderate hazard and 7-10 high hazard.

The biggest offenders are oxybenzone and octinoxate. EWG gives oxybenzone a high hazard rating of 8/10 and octinoxate a moderate hazard rating of 6/10. In addition, these two sunscreen filters have been found to be ocean contaminants that bleach coral. Therefore, Hawaii and Key West have banned the sale of sunscreens containing oxybenzone and octinoxate.

Health Canada, the FDA and several medical associations maintain that these chemical filters are safe only because there are no randomized clinical trials proving otherwise, not because they have actually been proven to be safe. However, we can be proactive and avoid these filters. There will never be double-blinded randomized clinical trials regarding the above because they would be unethical. 

Choose physical sunscreen filters:

Zinc oxide and titanium dioxide are safe, gentle and natural minerals that block both UVB (burning) rays and UVA rays, which are associated with photoaging and skin cancer. Also, since these minerals just sit on the skin to provide sun protection, they are comfortable and non-irritating.

Daniel