One of the harshest critics of industry on the issue of nanomaterial safety
– the Environmental Working Group (EWG), a US-based NGO that works to
expose threats to health and the environment - came to a "surprising"
conclusion: Sunscreens containing nanomaterials are among the most effective
and safest on the market.
Two years earlier, a Consumers Union investigation found that many sunscreen
products claiming to be "nano-free" actually contained manufactured
nanoparticles of zinc and titanium oxide. Friends of the Earth in 2007 published
a consumer guide to avoid nano-sunscreens which has been updated in July 2009.
All of these prior publications on the issue of nanoparticles in sunscreens
had in common that they presumed the use of nanoparticles to be dangerous (however,
sometimes based on rather weak scientific arguments) and recommended not using
such products.
EWG took a more comprehensive approach in testing over 1600 sunscreen products
and evaluating over 400 peer-reviewed studies on nanomaterials in sunscreens.
In their evaluation, EWG not only looked at whether or not products provide
broad-spectrum UV protection, but also at which sunscreens break down in the
sun, and at the full range of potentially hazardous sunscreen ingredients that
can absorb through the skin and into the body to pose other risks. The researchers
found that out of 1671 sunscreens on the market, 3 out of 5 either don’t
protect the skin from sun damage or contain hazardous chemicals. The results
are summarised in a database and a report.
The investigation also included sunscreens containing nanoscale titanium dioxide
and zinc oxide. According to the report, consumers who use sunscreens without
zinc and titanium are likely exposed to more UV radiation and greater numbers
of hazardous ingredients than consumers relying on zinc and titanium products
for sun protection.
A review of 16 studies on skin absorption of zinc oxide and titanium dioxide
nanoparticles revealed that nearly all studies showed no absorption of small-scale
zinc and titanium sunscreen ingredients through healthy skin. On balance, EWG
researchers found that zinc and titanium-based formulations are among the safest,
most effective sunscreens on the market based on available evidence.
On the other hand, for nano-scale ingredients, the NGO called for full labelling
so consumers can make informed choices. And, in the sense of a precautionary
approach, they only recommend using nano sunscreens if the nanomaterial brings
a clear advantage: "If it's not protecting your health, don't use it".
Contact & more information: Markus
Widmer
Source: The
Innovation Society
Posted August 21st, 2009
