A chemical that might be safe in its
normal-sized form may not be when it goes nano.
This
time of year, sunblock is part of the daily routine for many Americans. Wake
up, slather it on, and go outside.
For
those concerned about the chemicals we put on our bodies, sunblock represents a
double-edged sword. On one hand: what kind of chemicals am I putting on my skin
and spreading into the environment? On the other hand: I don’t want skin
cancer. Or, more immediately, a sunburn.
For
a parent with small children, sunblock is even more crucial. It’s difficult to
explain the dangers of staying out in the sun too long to your four-year-old.
An adult might do something sensible like sit in the shade or wear a hat.
When
you’re packing your kid off to spend a day at the beach with her friends, all
bets are off. And nothing feels worse than watching your kid suffer from red,
burning, peeling skin and knowing it’s your fault.
But
many sunscreens now pack unseen hazards: nanoparticles.
Manufacturers
often don’t disclose the presence of nanoparticles in their products. The
ingredient list might just say “titanium dioxide” or “zinc oxide,” omitting the
“nano.” But you’ll find these tiny particles in brands like Coppertone, Banana Boat, Neutrogena,Aveeno,
and even Burt’s Bees
“Chemical-Free” Sunscreen.
Sometimes,
these products even sport “non-nano”
labels, which take advantage of wiggle-room in definitions to
mislead consumers.
Nanotechnology
is so new that it’s not yet well-regulated or even well-understood. Scientists
are developing commercial uses for it faster than they’re assessing its safety.
However, some of the early research is troubling.
To
put it simply, size matters.
A chemical that might be safe in its normal-sized form might not be when it
goes nano. As the group As You Sow writes in
its issue brief on
nanotechnology in food, “Because of their small size, nanoparticles
are able to go places in the body that larger particles cannot.”
One study suggested
that particles might penetrate skin cells, causing DNA damage after exposure to
sunlight. The fear is that this could lead to cancer — exactly what sunblock is
intended to prevent.
If
you want to avoid nanoparticles until scientists have assessed safety concerns
and regulators have banished dangerous products from the market, here are a few
guidelines to follow.
First,
zinc oxide particles in sunscreen tend to be
larger than titanium dioxide products that appear clear on the
skin. They also provide better sun protection.
Second,
if a product contains titanium dioxide and it goes on your skin without a
whitish tint, it’s nano.
Third,
and probably most important, when you buy sunscreen, avoid the spray-on kind.
Yes, they’re convenient — especially for protecting a squirmy 4-year-old’s skin
— and can make it easier to keep sunblock off your hands. But while
nanoparticles won’t penetrate your skin, they can cause trouble if inhaled. And
you’re way more likely to inhale sunblock that’s sprayed instead of slathered.
Consumer Reports says
that if you have no choice besides a spray, spray it on your hands and then rub
it on your skin, particularly for children and for your face.
Finally,
you can skip the chemicals altogether if you simply wear protective clothing
like a hat, time your visit to the beach so you aren’t there when the sun is
strongest, or sit in the shade while you’re outside.
Consumers
can’t solve this quandary on their own and sunscreen manufacturers haven’t done
enough to find a solution. What we really need is adequate labeling so that
we’ll all know what we’re buying and better regulations that will keep the
truly dangerous products off the shelves.
OtherWords columnist Jill Richardson is
the author of Recipe for America: Why Our Food System Is Broken and
What We Can Do to Fix It. OtherWords.org