Friday, May 10, 2019

Sunscreen may not be as harmless as we thought


Wired reports:

Today, researchers at the FDA revealed the results of a small clinical trial designed to test how four of the most common sun-filtering molecules on the market behave after they’ve been sprayed on and rubbed in. The results, published in the journal JAMA, show that contrary to what sunscreen manufacturers have been saying, UV-blocking chemicals do seep into circulation. Now, don’t panic and toss your tubes. There’s no evidence yet that they’re doing anything harmful inside the body. But the revelation will have serious impacts on sunscreen manufacturers going forward, and may change what options you’ll find on drugstore shelves before the year is out.

“Everyone had always thought that because these are intended to work on the surface of the skin that they wouldn’t be absorbed, but they are,” says Theresa Michele, director of the FDA’s division of nonprescription drug products, and coauthor on the FDA-funded study. Her team found that it took only a few hours after the application of sunscreen for the photoprotective chemicals to infiltrate the bloodstream and shoot up to concentrations above the FDA’s toxicology threshold that triggers further safety testing.

. . .

The fact that these sun-filtering molecules do penetrate into the circulation system does not on its own mean that such ingredients are unsafe. “There might be nothing, and that would be great,” says Kanade Shinkai, a dermatologist at UC San Francisco and editor in chief of JAMA Dermatology. “But the problem is that we just don’t know.” The bottom line, she says, is that although the evidence is irrefutable that the sun causes skin cancer, scientists know a lot less about sunscreen chemicals’ relative risks and benefits.

There's more at the link.

This is particularly worrying to me, in that I can see the long-term effects of sun on my forearms and other areas of skin.  Exposed to the burning African sun for years as I was, it took its toll;  and it would have taken a greater one if it wasn't for large quantities of sunscreen, liberally applied.  Now I wonder whether the sunscreen might not have posed more of a danger than the sun!

This will bear watching.

Peter

12 comments:

Mogrith said...

My guess while nor harmless you are better off using it.

But it can have another effect. https://wattsupwiththat.com/2015/10/20/oops-it-may-not-be-ocean-acidification-killing-coral-after-all-common-chemical-found-in-sunscreen-is-poisonous-to-coral-reefs/

Angus McThag said...

I'm going to guess that after so many decades of use that if it was really harmful, there'd be lots of cases tying it to disease already.

Kevin said...

Sunscreen seems to be another product (joining dental floss) that lacks peer reviewed evidence based science.
https://www.outsideonline.com/2380751/sunscreen-sun-exposure-skin-cancer-science

Tal Hartsfeld said...

I find "panacea" and "snake oil" to be, to a large degree, synonyms.
Being alive is the leading cause of death, and so far there still is no known cure for it.

Orvan Taurus said...

I really wonder who many chemicals that are presumed not to traverse the skin, really do. I suspect the idea of "it stays on the surface" is generally wrong -- and that in most cases it's simply that exposure is avoid or minimized (washed off right off) with a few exceptions (sunscreen, cosmetics) and a few horrifying cases (e.g. dimethylmercury) where even minimal exposure exposure time is far too much.

Peter B said...

I really wonder how many chemicals that are presumed not to traverse the skin, really do

Almost everything will traverse the skin to some extent If it's on your skin for any length of time. A fair amount of it is getting into your blood if it's fat soluble.



But minerals will go in, too.

smoky said...

We were all killed off by Y2K so it doesn't matter anyway.

John Ray said...

Our skin is a living organ. I suspect it absorbs everything with which it makes contact. It's a risk/reward decision. I know of nobody who died or became permanently ill from sunscreen. If one would otherwise live to be 150 yrs. old, one may regret having used copious amounts of the stuff. But I, for one, will not worry about that prospect. Meanwhile, as I sip my afternoon vodka....

Shell said...

Oh, horse puckey. I stopped paying any mind to news reports of the latest "scientific study" warning us about what's going to kill us off about fifteen years ago - not that I did much before then - when one trumpeted "HAVING SEX CAN CAUSE CANCER!"

Hellwiddit, we all gotta go some time some way.

Sherm said...

It's as if nature, in all it's many guises, is conspiring to be sure none of us get out of here alive.

capt fast said...

I find long sleeved shirts, pants and wide brimmed hats to be effective as a sunscreen aid. It is probably too late for me to avoid skin cancer, as in my youth I was a fool-more so than I am now. Understanding the physics of radiation, I was always doubtful of the efficacy of "lotions".
Some "sun screens" probably contain that element unobtainium alloyed with invisibilium in a matrix of superdoesit sauce in order to deflect the radiations of trillions of ergs of energy pouring onto our planet on any given day(attention trolls, I say this in jest) no doubt some may work, but then there is the advertising side step to be considered.

urbane legend said...

I believe smoky is correct. If not, I hope to avoid cancer from sex by having a massive heart attack during a particularly stimulating episode.