Over the past four weeks,
Risk Bites has explored what advanced materials
are, and why so many people are so
excited about them. But what about the downsides?
Do new materials automatically come pre-packaged with new risks?
Exploring the potential ways new materials can cause harm
is important. If you want to make money from advanced materials and the products
they are used in,
maiming or killing your clinetelle in the process
is not a great business strategy. And surprising as it may seem,
many folks in business would rather be improving people's lives
than making them worse. But if you've got a brand new, never-before-used material,
how do you know what it might do that you probably don't want it to do?
One approach is to assume the worst -
maybe that novel never-before-seen nanoparticle for instance
could borrow into your brain replicate itself and bring about the next
zombie apocalypse!
Maybe it could. But probably it won't.
Fortunately, a firm grasp of scientific reality,
past experience, and some risk analysis know-how
go a long way to helping predict the likely ways a new material might be
harmful
and how that harm can be avoided. The first thing to ask if you're interested
in health risk is -
can this new wonder-material get into your body?
The obvious ways material can get into your body
are through your mouth, or going up your nose, or diffusing through
your skin. If there's a way in, we need to consider the harm that could be caused
by the material as a result.
But if there isn't a way in, there's little chance of harm occuring.
For example: a single carbon nanotube
could be inhaled or ingested and get into your body that way.
But wrap it up in an iPhone, and unless you have some odd
eating habits, it'll probably stay in the phone and not get into you.
But what if an advanced material does get into your body?
Over millennia, we've lived in some pretty cruddy environments as humans,
and as a result our bodies have evolved to handle stuff that could be harmful.
It's a neat survival trick that has helped us to stick around for as long as we
have.
For many advanced materials, our bodies will process and eliminate them
just as effectively as other materials. Just because we think they're fancy
doesn't mean our bodies do. But there are some warning signs we've learned to look
out for in materials that our bodies don't handle so well.
Particles that get into us and don't dissolve or degrade easily aren't great news,
for instance.
Neither are particles that are long and thin (like fibers),
or crystalline, or small enough to slip into places they shouldn't.
Or materials the release known toxic chemicals.
These are all characteristics that scream
"watch out!" if they are present in a brand-new, never-before-
tested advanced material. In other words,
out of the vast array of advanced materials we could be using,
some may need to be handled with special care.
But only a small number these materials will have the potential
to get into our bodies and cause harm. Of these,
only some will overcome or slip by
the body's defenses and caused serious harm. And of these,
fewer still will cause harm in ways we weren't expecting.
And a very small number of materials indeed
will lead to new diseases. As a colleague of mine likes to point out,
"The body only has a limited number of ways of saying
'ouch!'"
By using scientific understanding and expert knowledge,
many of the potential risks associated with advanced materials
can be spotted and managed - or avoided altogether.
That said, there are bound to be
unknown unknowns - those things that a new-fangled material does
that no one thought of beforehand. While second-guessing what these might look
like can be a dangerous game,
it's important to continue researching possible risks -
just so we're not caught with our pants down when something unpleasant
does eventually turn up! Next week
Risk Bites will explore the tension between novel behavior and
novel risks in more depth. Until then, though, stay safe.