Sunscreens exceed “safe” toxin levels within just hours

Today is Memorial Day—the unofficial start of summer.

So, I hope you’re starting to spend at least 10 to 15 minutes each day in the sun without sunscreen.

Using sunscreen blocks your body’s production of vitamin D. Plus, there are harmful chemicals in sunscreen, as I often warn. And now, a new clinical trial has found that your body absorbs these chemicals into the bloodstream, reaching toxic levels within just hours!

Considering the fact that sunscreen has become a ubiquitous part of summer for most people (thanks to misguided “advice” from dermatologists), this discovery should have made headlines in every major media outlet.

But it didn’t.

So, let’s dive right in, and I’ll tell you what the so-called “experts” won’t…

FDA takes nearly unprecedented step to conduct its own trial

The U.S. Food and Drug Administration (FDA) has been investigating the safety of sunscreens since the 1970s. Initially it was thought that the ingredients in sunscreen sat on the surface of the skin.

But lately, there’s been growing concern that these ingredients make their way into the bloodstream and tissues. And the FDA has been asking sunscreen manufacturers to conduct research to analyze this concern for years.

Of course, this important research never happened. (Or if it did, the manufacturers never made it public.)

So, finally, the FDA took the nearly unprecedented step to conduct the research itself. (An action so rare that it illustrates the seriousness of this problem!)

Chemicals exceed “safe” levels in just hours

For the new trial, FDA researchers enrolled 24 healthy participants to test four commercially available sunscreens (two sprays, one lotion, and one cream).

The participants applied the sunscreen according to labeling instructions four times a day for a total of four days.

Then, researchers tested the participants’ blood for the presence of avobenzone, ecamsule, octocrylene, and oxybenzone—four common chemicals found in sunscreen. In total, they took 30 blood samples over seven days from each participant. The study was also conducted under controlled indoor conditions without exposure to outdoor heat, humidity, sunlight, or water.

It turns out, after just four applications on the first day, all but one of the participants already had concentrations of the chemicals greater than 0.5 nanogram/milliliter (ng/mL) detected in their blood.

In fact, concentrations of avobenzone and octocrylene exceeded 0.5 ng/mL within six hours after the first application. And concentrations of oxybenzone exceeded 0.5 ng/mL after just two hours.

Now, here’s why 0.5 ng/mL is so important…

  1. The FDA determined that any sunscreen that causes concentrations higher than 0.5 ng/mL should be studied further.
  2. These concentrations are based on an index called Threshold of Toxicological Concern (TTC), which is used to estimate cancer risk. And according to the TTC, concentrations higher than 0.5 ng/mL for any one of these four chemicals means the cancer risk would be greater than 1 case in 100,000 after a single dose.
  3. The International Council for Harmonization, an independent group of regulatory authorities that looks at scientific and technical issues involving drugs, linked levels higher than 0.5 ng/mL to an increased cancer risk.

And, it gets worse

Blood concentrations magnify on subsequent days

When you spend a full day in the sun, you probably reapply your sunscreen several times. And in this study, the participants applied sunscreen four times a day.

But researchers found strong evidence that these toxic chemicals actually build up in your blood over time after subsequent applications.

In fact, with one type of sunscreen, concentrations of oxybenzone reached as high as 210 ng/mL in 57 hours. That’s 42 times higher than the “safety” threshold!

So, what does that mean for cancer risk?

Well, let’s do some simple math. Let’s assume all four ingredients reach a concentration of 0.5 ng/mL with one application. Over four days, the participants reapplied sunscreen 16 times. And if the concentrations accumulate, it brings the cancer risk up to 16 cases in 100,000.

Unfortunately, this estimated cancer risk is just conjecture, as researchers haven’t thoroughly studied the real human effects of concentrations beyond 0.5 ng/mL in any of these chemicals.

But we do know that at higher concentrations, oxybenzone accumulates in amniotic fluid, breast milk, and urine…not only the blood. Higher concentrations also affect the endocrine system.

Unfortunately, we just don’t know enough about the effects of the ingredients in sunscreens.

In fact, in an editorial that accompanied the study, authors noted that sunscreen users reasonably presume that basic studies have been conducted to support the safety and effectiveness of sunscreen products. “However, sunscreens haven’t been subjected to standard drug safety testing, and clinicians and consumers lack data on systemic drug levels despite decades of widespread use.”

So, at the end of the day, I still give the FDA a failing grade on this issue…

It did finally study the problem on its own. But the research is long overdue. And we still need more answers.

Plus, the FDA’s guidelines don’t go far enough to clearly determine the safety of sunscreens. In fact, its review and approval process for OTC sunscreens follows standards set before the modern era of drug evaluation. And this ancient, pathetic benchmark needs to change.

Bottom line—avoid commercial sunscreens. They’re clearly unsafe, with too many unknowns.

Instead, simply aim to spend 10 to 15 minutes a day in the sun without sunscreen. This is enough time for your skin to naturally produce vitamin D and melanin (a pigment that works as a natural sun protectant). And if you’re fair-skinned and plan to spend all day in the sun, try making your own natural sunscreen to avoid burning.

P.S. There are a lot of medical myths out there when it comes to the effect of the sun on your skin. In fact, I wrote about this at length in the August 2018 issue of my Insiders’ Cures newsletter (“Shedding light on better skin protection”). To read this article—and my entire archive—subscribers can go to and log in by clicking on the subscribers tab.

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“FDA Finds High Systemic Absorption of Sunscreen Ingredients.” Medscape, 5/6/19. (