Five things worth knowing about nanoparticles and sunscreens

Shopping for sunscreen is a complicated
business

Even before you get to the big questions
like do you go for the spray on stuff

or the slap on cream,

there's the issue with how safe the product
is.

And that inevitably leads to the question of
whether you go for conventional

sunscreens - the ones that use chemicals
like

oxybenzone or avobenzone, or one at the
newfangled

nano-particles sunscreens. And if you do
go nano,

just how safe are those tiny little
particles you're about to spread on

your skin?

Nanoparticle sunscreens use
microscopically small particles of zinc

oxide or titanium dioxide.

You can usually tell if a sunscreen uses
nanoparticles because it lists one or

both of these materials

on the label. Companies have been using these substances for a decade or so now

claiming that they make for a better
sunscreen.

But first some users, there are lingering
doubts about

their safety. So what do you need to know
when deciding whether to go

nano or not before braving the sun's
rays? Here are

five things that may be helpful:

One: Nanoparticles in sunscreen stay on on

top of your skin, and don't past through
it

When manufacturers started to use these
minuscule particles,

researchers wondered whether they could
in fact slip in between your skin cells

or even get into the cells themselves.

Fortunately, after several years of
research,

it looks like healthy skin is great at
preventing nanoparticles

getting into your body.

Two: Nanoparticles in sunscreen work by
reflecting harmful

ultraviolet light away from your skin,
while allowing

visible light through. Because of this
they create a

barely visible protective barrier, which
is great if you'd rather not look like

you've just been whitewashed.

What's more, they protect you as soon as
they've been applied,

unlike many of the more conventional
sunscreens that need

time to settle into your skin before before
they're fully effective.

Three: Uncoated nanoparticles of

titanium dioxide and zinc oxide can
produce harmful chemicals called

free radicals when exposed to sunlight.
To avoid this,

sunscreen manufacturers coat them with
a thin layer of materials like silica

or alumina.

The layer prevents free radical
formation, and transforms potentially

harmful particles

into safe ones.

Four: Non nano sunscreens may be more harmful than

nano sunscreens, according to some
research. Conventional ingredients like

oxybenzone may lead to allergic
reactions with some people. And

small quantities can penetrate
through your skin,

and into your body, where there's a
chance that they may cause problems by

behaving like

human hormones. In contrast, at this point

there is no evidence that nanoparticles
behaved similarly.

Five:

inhaling large quantities of titanium
dioxide and zinc oxide nanoparticles

probably isn't a good idea. Research has
shown that,

even though these substances are likely to
be okay if inhaled in small amounts,

smaller particles definitely do do
more damage than larger particles if

they get into your lungs.

So you might just want to watch what
you're breathing while using one of those

spray on nano sunscreens.

Finally, whether you end up opting for

nano or non nano sunscreens, or using some other former protection,

remember that exposing unprotected skin
to the sun's UV rays

is one option that is definitely not
safe here.

If you have any thoughts on nano
sunscreens or

sun protection in general, please do
join the conversation in the comments.

And remember to check out the additional
resources in blurb below.