Page 70 - LIN March-2023 50-84-sent

Technically Speaking

that old devil sun
sun

by Dave Trecker
e’re called the Sunshine State for a reason. We have, are easily formulated into oils and salves, but their small size eases
W absorption through the skin. One big plus, one big minus.
W
on average, 237 sunny days a year, 266 in Southwest
Florida. The five sunniest cities are Bonita Springs,
A recent article in Chemical & Engineering News frames the
Ft. Myers Beach, Marco Island, Naples and Punta Gorda. dilemma. Unlike most of the rest of the world, the United States
That’s one of the reasons people move here. Why put up with treats sunscreens like over-the-counter medicines. Their approval
the gloomy Northeast or the cloudy, cold Midwest if you can live requires testing to show they are GRAS, “generally regarded
in sunny Florida? as safe.” Because of the risk of bodily absorption, the tests can
But there’s a downside. That bright, warming sun causes skin take years and cost tens of millions of dollars – not much for an
cancer. Solar ultraviolet radiation is responsible for 10,000 deaths expensive drug, but a killer for a cheap sunblock.
a year in the United States, a number that has been increasing at Putting the final nail in the coffin, scientists recently published
an alarming rate. a study showing that commonly used organic UV filters often
How can that be, you ask? We have the best technology in “turn up in the bloodstream at levels that trigger a toxicology study
the world. We have super computers that can solve any problem. requirement.” That isn’t to say they’re dangerous. But they must be
We can guide missiles to a pinpoint target, develop life-saving tested. That applies to some 15 existing sunblocks and a backlog of
vaccines, explore outer space. Surely we can soak up UV rays. six to seven new ones.
And we can, of course. We have a whole bunch of sunscreens The situation is far different overseas. Most of the rest of the
to do just that, products widely available at CVS and Walgreens. world treats sunblocks as cosmetics, comfortable that the small
It’s not like we have to go unprotected. Pick up some sunblock organics have been used for decades without serious problems.
and slather it on. So where do we go from here? Help may be on the way.
So what's the problem? A triazole derivative discovered 20 years ago has been
So w
em?
he pr
obl
hat's t
resurrected and exhaustively examined. Called bemotrizinol, it
The problem is medical studies show that many of the most
seems to meet all of the requirements. It’s a big molecule. It soaks
widely used sunblocks are absorbed into the bloodstream.
up a wide band of UV light. It’s stable, easily formulated and clear
Without data to prove that no harm results, the FDA is poised
when applied. Little, if any, passes into the bloodstream, and the
to yank approval of these chemicals. Pull them off of the shelves.
toxicology looks great.
And no new products can be added to the mix without extensive
A company called DSM recently completed testing of
testing.
bemotrizinol and plans to submit the data to the FDA by
g ab
in
e?
t her
ou
Just w
e we t
Just what are we talking about here? mid-2023. Rapid approval is expected.
alk
hat ar
Sunscreens work in several ways.
What should we do in the meantime?
W hat should we do in t he m eantim e?
Inorganics like titanium dioxide and zinc oxide simply reflect
Experts say to plaster on the titanium dioxide or zinc oxide.
the UV rays. They are not absorbed through the skin, a big plus.
Looking like a kabuki warrior isn’t such a bad thing.
But they are paint pigments. They make you look like a kabuki
warrior, a big minus for most.
About the Author
Organic sunscreens function differently. They soak up the light Ab ou t t he Au t hor
energy and transfer it to thermal energy, blunting the threat of Dr. Trecker is a chemist and retired Pfizer executive living
sunburn. Oxybenzone, octinoxate, avobenzone, homosalate and in Naples.
others operate this way. Because they are small molecules, they
70 Life in Naples | March 2023