Shining A Light On The Sun Blog Series - Part 4

Ronit Mor, ND

About The Efficacy And Safety Of Sunscreens
Are you aware that the FDA itself says it is “not aware of data demonstrating that sunscreen use helps prevent skin cancer”? According to the Environmental Working Group’s (EWG) 11th Annual Sunscreen Guide, there are currently more than 880 beach and sport sunscreens, 480 moisturizers and 120 lip products with SPF but the surprising truth is this: beyond the knowledge that sunscreens prevent sunburns, little else is known about the safety and efficacy of sunscreen lotions and sprays.

Furthermore, the FDA allows most sunscreens to claim that they play a role in preventing skin cancer even though there is little scientific evidence to suggest that sunscreen alone reduces cancer risk, particularly for melanoma, the deadliest type of skin cancer. The fact remains that despite the public significantly reduced exposure to sunlight and a multi-billion dollar sunscreen industry, melanoma rates have tripled over the past three decades.
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Surprising Facts About Sunscreens
There are many disturbing facts that might tempt us to abandon sunscreen altogether. Here are some of the more surprising facts about sunscreens, adapted from the EWG report:

• No proof that sunscreen prevents skin cancer. The FDA’s 2007 draft sunscreen safety regulations say: “FDA is not aware of data demonstrating that sunscreen use alone helps prevent skin cancer.” The International Agency for Research on Cancer (IARC) agrees. IARC recommends clothing, hats and shade as primary barriers to UV radiation and writes that “sunscreens should not be the first choice for skin cancer prevention and should not be used as the sole agent for protection against the sun.”

• Sunscreens might increase the risk of the deadliest form of skin cancer for some people. Are you aware that a 2007 meta-analysis of 17 (out of 18 known) studies on the subject concluded that: “there was no statistically significant effect of use of sunscreens on risk of melanoma”? In fact, this study has even detected an increased risk of melanoma among sunscreen users in latitudes greater than 40 degrees. What this study further reveals is that there are virtually no studies done on whether sunscreen has any benefit or harm for those with darker skin or for those living significantly south of the equator.

• Anything that you rub on your skin enters your blood stream in about 30 seconds. That could pose a problem if you are slathering your skin with poisonous chemicals. Active ingredients in sunscreens come in two forms: mineral and chemical filters. Each uses a different mechanism for protecting skin and maintaining stability in sunlight. The most common sunscreens on the market contain chemical filters. These products typically include a combination of two to six of the following active ingredients: oxybenzone, avobenzone, octisalate, octocrylene, homosalate and octinoxate. Chemicals filters are easily absorbed through the skin and into the body and can cross the placenta and enter unborn children. Mineral filters consist of zinc oxide and titanium dioxide. Mineral filters usually rate as safer in the EWG research, however most of these mineral filters are used in nano particle form. This means these ingredients are so small they may be inhaled (spray sunscreens) or enter the bloodstream very easily. According to the International Agency for Research on Cancer (IARC), when titanium dioxide is inhaled, it is considered a potential carcinogen.

Sunscreen Ingredients Better Left Untouched
The Danish EPA recently reviewed the safety of active ingredients in sunscreen and concluded that most ingredients lacked information to ensure their safety. Sixteen of the nineteen ingredients studied had no information about their potential adverse effects in humans. And while the published studies suggest that several chemical filters interact with human sex or thyroid hormones, none of the ingredients had sufficient information to determine the potential risks to humans from hormone disruption. The Danish EPA reported adverse effects observed in laboratory animals exposed to UV filters include reproductive/developmental toxicity and disruption of the hypothalamic-pituitary-thyroid axis (HPT). Following are ingredients you might want to avoid:

• Retinyl palmitate (a form of vitamin A) may speed the development of cancer. Inactive ingredients make up 50 to 70 percent of a sunscreen product. Retinyl palmitate and methylisothiazolinone are such ingredients. Recently available data from an FDA study indicate that retinyl palmitate, when applied to the skin in the presence of sunlight, may speed the development of skin tumors and lesions. Methylisothiazolinone, a preservative, has been found in laboratory studies showed to be a skin sensitizer and allergen.
• Oxybenzone. Found in almost all chemical sunscreens, oxybenzone is an allergen and potential endocrine disruptor. It is easily absorbed through the skin, particularly in children, and can interfere with hormone development.

• Nanoparticles. Nanoscale particles of minerals are often found in titanium or zinc based sunscreens. These tiny particles have not fully been studies and there are no regulations governing their use or labelling in the U.S.

• High SPF factors. High SPF ratings were found by the FDA to be “inherently misleading”. What’s more, products with these ratings often contain more of the above toxic ingredients.

• Retinol or retinyl palmitate. May actually speed the development of skin tumors and lesions.

• Fragrance or Perfumes. These are considered trade secrets in the U.S. This means a multitude of chemicals, including suspected neurotoxins and endocrine disruptors, may be hidden behind these seemingly innocent terms.

• Parabens. Parabens are endocrine-disrupting chemicals that mimic the female hormone estrogen and are linked with reproductive disorders in boys and possibly cancers in women.

• PABA (Para-aminobenzoic acid). Has high incidence of allergic reactions in response to its use.

• All spray sunscreens. The FDA announced their investigation of spray sunscreen safety in 2011, but have yet to release a verdict. However, Consumer Reports recently issued a warning against the sprays that advises parents to stay away from using them on children.

For Part 5 of this blog series, click here.