here comes the sun: the dangers of chemical sunscreen

What a glorious feeling to again feel some warmth and sunshine. Spring cannot arrive soon enough, especially those of us living in the areas of frequent, sporadic snowfall.

This time of year also means we’re paying more attention to our skin as we take off the many layers of clothing and get some tan lines. We’ve been told many a time about the importance of wearing sunscreen, to stay away from tanning beds, and looking out for any odd-looking moles and signs of skin cancer. However, have we considered what goes into protecting against sun damage?


That’s right: not all sunscreens are made equal. In particular, there is a huge difference between choosing mineral- and chemical-based sunscreens. When choosing healthier options for ourselves and the environment, we need to go beyond the SPF number and really see what sets apart some sunscreens over others.

What’s the difference?

Physical sunscreens use physical UV filters, while chemical sunscreens use chemical UV filters. That means physical sunscreens protect your skin from the sun by deflecting or blocking the sun’s rays, whereas chemical sunscreens work by absorbing the sun’s rays. Some chemical filters can scatter sun rays, but still mostly just absorb them. The UV filters on non-chemical sunscreens are typically titanium oxide and zinc oxide, and chemical sunscreens include ingredients like helioplex, octylcrylene, avobenzone, and more hard-to-pronounce names.

While I’ll go into more detail as to how these substances interact with our bodies and how they’re produced, in all chemical sunscreens and some physical ones, the problem we face is when our body absorbs them. While many physical sunscreens stay on top of the skin to work, recently more physical sunscreens are now made into nanoparticles that can be absorbed.

The reason people often opt for smaller particle sizes in sunscreen is because it feel think and heavy, leaving a white cast on the skin and potentially blocking pores and causing breakouts. Cosmetics will turn to micronization, making particles smaller, to avoid this not-so pretty look, but it comes with a trade-off. The more micronized the particles, the thinner the ‘shield’ and the less protected you are. Larger particle sizes protect better (but they make skin appear whiter).

Chemical concerns.

The micronized particles are more of a growing debate surrounding physical sunscreens. Chemical sunscreens, as mentioned earlier, absorb UV rays and convert them to heat that is dispersed in the skin. Laboratory studies indicate that some chemical UV filters may mimic hormones, and physicians report sunscreen-related skin allergies, which raises important questions about unintended human health consequences from frequent sunscreen application.

For example, one ingredient oxybenzone is in nearly 65 percent of all sunscreens. The Centers for Disease Control and Prevention has detected oxybenzone in more than 96 percent of the American population. With as much sunscreen you probably put on your body, the fact we’re absorbing all of this without necessarily knowing the long-term repercussions can be hard to swallow.

Research reveals that the chemicals commonly used in sunscreen are endocrine disruptors, estrogenic and may interfere with thyroid and other hormone processes in the body. Of the 1,400+ sunscreens tested by the EWG, only 5% met their safety standards and over 40% were listed as potentially contributing to skin cancer. One of the reasons is that a Vitamin A derivative, retinyl palmitate, that is often used in sunscreens was shown to speed up the growth of cancerous cells by 21%.

Environmental aftermath.

As with much of our personal products and toiletries, what we don’t use ends up in the garbage, which ends up in a landfill, which ends up absorbed by other living beings.

There’s still a lot we don’t know about how sunscreen ingredients affect the environment, but if they cause issues in humans, chances are they aren’t great for our planet and all who inhabit it. Though human health and planetary health aren’t exactly the same thing, they are related issues: Any mineral or chemical that might be harmful to humans could also damage wildlife and destabilize ecosystems. Though the studies aren’t exhaustive, researchers have found detectable levels of chemical UV filters in lakes, oceans, and rivers around the world, with the highest concentrations found near wastewater treatment plants.

Again, we probably go back to the answer of just choosing mineral sunscreens over chemical sunscreens, but let’s return again to the growing trend of micronizing titanium and zinc oxides. They’ve been shown to be toxic to zebrafish and potentially harmful to rainbow trout. Some kinds of titanium dioxide nano-particles may also have harmful effects on algae.

Not to mention how these ingredients are first produced. Creating titanium dioxide can result in large amounts of iron sulfate waste or smaller amounts of the more hazardous iron chloride waste. And manufacturing the nano-sized versions may require plenty of extra energy plus more purifying solvent, which generates significant amounts of waste that may be hazardous. It’s hard to tell exactly how the chemicals stack up in terms of production, but metal mining releases more than twice the amount of toxic chemicals as the chemicals industry, according to the EPA.

What’s the best option?

The world of sunscreens is a mixed bag, but that doesn’t deter the necessity for preventative measures against excessive sun exposure. If you want to avoid navigating the world of sunscreens altogether, you can always cover up your skin when outside by wearing light layers and hats.

There are definitely some awesome sunscreen alternatives that use non-nano forms of zinc oxide and use other healthy, natural ingredients that prevent absorbing not-so great things. Check out my Amazon links to check for yourself some of my top choices.

At the end of the day, it’s up to you how you want to protect yourself. Just make sure you’re aware of what you’re putting on (and in) your body and how that might affect the environment. If there’s an affordable and more sustainable option out there, why not choose that instead?

Take care, and keep the faith. -Allie

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