There are two basic types of sunscreens — chemical and physical. Each work differently to block the sun’s rays.

Chemical sunscreens protect skin by absorbing the sun’s rays. They do this by seeping into your skin. This is why chemical sunscreens apply smoothly, without leaving a thick film, using active ingredients such as oxybenzone, octinoxate, octisalate and avobenzone, which are created by extracting and processing various chemicals from crude oil. Such derived substances are known collectively as petrochemicals.

The problem is that many petrochemicals disrupt endocrine and hormone activity, and what’s worse, they actually encourage UVA damage, deeper in the skin.

In short, chemical sunscreens protect the skin’s surface from the temporary discomfort of sunburn by simply passing the problem deeper, where it festers unnoticed until years later when dermatologists begin diagnosing serious skin problems including skin cancer.

 

 

What makes petrochemicals so bad in sunscreen?

Quite simply, petrochemicals weren’t meant to interact directly with humans or animals. The list of reasons is long and growing. Here are just a few of those known so far.

  • Petrochemicals penetrate skin, causing bioaccumulation and systemic exposure, building up in the blood and fat deposits. Toxic in themselves, they damage DNA over time.
  • Many petrochemicals (like oxybenzone) mimic estrogen in the human body. This is linked with numerous diseases, including cancer and early female puberty.
  • Many petrochemicals do not biodegrade, accumulating in water supplies and ocean sediments, feminizing fish and damaging coral. Most tropical aquatic parks have banned petrochemical sunscreens.
  • Petrochemical sunscreens exchange UV damage for toxic chemical damage. Unable to convert UV rays into harmless energy as well as mineral sunscreens, active petrochemical ingredients are actually photo-degraded by both UV energy and each other — breaking chemical bonds, disabling UV absorption capacity, and creating reactive free radicals in the body. These events are not only linked to the development of cancer, they can produce severe inflammatory skin reactions – in essence, chemical burns.
  • Individual petrochemicals absorb UV rays within diverse finite wavelength ranges. In other words, no single petrochemical is broad spectrum, and so petrochemical sunscreens must use a cobbled amalgamation of compounds, all with various abilities to do harm to the body while they degrade their neighbors’ solar protective capabilities.

Compared to environmental contaminants in our air, food and water, chemical sunscreen produces exposure levels thousands to millions of times higher.

 

In Closing: What is chemical sunscreen?

In the final analysis, do chemical sunscreens work? In the short term, yes, since most who use such products do avoid sunburn. However, they fail miserably for long term protection, evidenced by the fact that while per capita, inflation adjusted use of chemical sunscreens has quadrupled since 1975, rates of skin cancer per capita have tripled in that same time period.

Traditional sunscreens made from petrochemicals, even those marketed as “broad spectrum” or “for sensitive skin” or “baby safe,” simply do not deliver on their promise of staying safe in the sun.

The truth is that the only safe, fully effective sunscreens, both for short term and long term protection, use zinc oxide (not titanium dioxide, which contains a toxic heavy metal and doesn’t disperse UV energy as efficiently as zinc oxide) as their sole active ingredient.