Nanoparticles damage DNA. Nanoparticles cause cancer. Nanoparticles kill
These are just some of the frames applied by the mainstream media to research
publications released in the last year or so. Whilst many celebrate the amazing
properties these novel materials can bring to technological applications, others
fear we may be opening a modern Pandora's box. When the Center for Biological and
Environmental Nanotechnology (CBEN) at Rice University was funded in 2001,
there was almost no scientific literature on the potential environmental, health
and safety risks (EHS) of engineered nanoparticles.
CBEN began some of the
earliest focused research to explore these issues even as its scientists pursued
the "sunny side" of nano-enabled medical therapies and water treatment.
Journalists quickly realized that nano-risks might be newsworthy and started
posting stories whenever a new paper linking nanoparticles and unwanted outcomes
Temptation #1: Generalizing Results from One Study to All of
It is tempting-but irresponsible-to draw general conclusions about
nanoparticle risks from a single paper. Science rarely works that way,
especially in young and emerging fields where research practice has not been
sufficiently standardized and old methods need to be validated for use with new
materials. Moreover, the diversity of objects, devices and nanoparticle types
that can be included under the umbrella term "nanotechnology" defies easy
answers. A better approach is to look at the whole corpus and try to tease out
some general themes that can guide future research.
As late as 2005, the limited number of extant papers were scattered in
diverse journals, making the results difficult to find, much less compare or
collate into a cohesive message for journalists, policymakers and risk managers.
The group that I direct, the International Council on Nanotechnology, set out to make it
easier to find these needles in the nano-haystack.
Our first project was the creation of the Virtual Journal of
NanoEHS, the world's first comprehensive database of research publications
addressing this aspect of nanotechnology. The papers are indexed according to
particle type, exposure route and other factors and catalogued with full
bibliographic information and a link to the journal's website. We've added an
analytical tool that allows one to track trends in the field and print out
customized reports well as a commenting and rating function to provide a forum
for community discussion of the research.
Temptation #2: Mischaracterizing the Impacts Research as Either Non-Existent
What can we learn from this body of work? First, there's a lot more data now
than there was back in the early days. Between 2001 and 2008 (the last year for
which complete data are available), the annual NanoEHS publication rate grew
between 20-120% per year. With over 3600 individual papers in the VJ it's
difficult to defend the claim that we don't know anything about nanoparticles'
However, if we dig into the research base it becomes equally difficult to say
that all these data are conclusive. A recent analysis found that much of the
"nanotoxicology" research is done in vitro, focusing on acute toxicity and
mortality induced by native nanoparticles, with limited relevance to human
health or environmental impacts and little attention to consumer
products.1 We are still a long way from having the
knowledge base needed to develop quantitative tools for predicting nanomaterial
behavior. These knowledge gaps have been laid in numerous documents, including
an ICON workshop report
on predicting nanobiointeractions.
Taken as a whole, the collected research does lead to a few conclusions that
have immediate relevance, albeit mostly to people working directly with
nanoparticles as opposed to consumers. Simply put,
1. Nanoscale materials may act in ways different from their non-nanoscale
2. Different physical and chemical properties may result in
different biological interactions.
3. Some of these interactions will be
These facts suggest that it is prudent for people handling native
nanoparticles in the workplace or research lab to take reasonable precautions to
avoid exposure to nanomaterials.
Temptation #3: Basing Risk Management Decisions on Non-Nanoscale
As quantitative hazard and exposure assessments are still lacking for most
nanoparticles, it is tempting to base risk management decisions on non-nanoscale
analogs. But Facts # 1 and 2 argue against this approach. Say it with me,
"Nanotubes ‚ Synthetic Graphite." In the meantime qualitative risk management
tools such as control banding are being investigated for application to
This particular approach uses task-specific information about the form of the
nanomaterial and the duration of the task along with any known hazard
information from the non-nanoscale analog to make common-sense recommendations
for safe handling. It may make sense to adopt a control banding approach in the
interim as more quantitative assessments are developed. General guidance is also
available from various governmental agencies3 as
well as at the GoodNanoGuide.
The state of knowledge of nanomaterials' environmental, health and safety
impacts is in an awkward phase where we have just enough information to believe
there may be reason for caution but not enough upon which to base robust
quantitative risk management decisions. Much more information is needed to
inform risk management in the workplace and decision-making in the marketplace.
This information needs to be based on sound science that utilizes validated
techniques and is more accessible to people outside of government and industry.
Avoid the temptations to generalize or mischaracterize the nano-EHS literature
or seek lazy solutions to risk management. I believe we can work safely with
nanomaterials but only if we acknowledge the unknowns, communicate honestly
about them and redouble our efforts to reduce them.
All opinions expressed in this piece are my own and should not be taken as
the opinions of the International Council on Nanotechnology, Center for
Biological and Environmental Nanotechnology or Rice University.
1. Ostrowski, A.D., et al., Nanotoxicology: characterizing the
scientific literature, 2000-2007. Journal of Nanoparticle Research, 2009. 11(2):
2. Zalk, D.M., S.Y. Paik, and P. Swuste, Evaluating
the Control Banding Nanotool: a qualitative risk assessment method for
controlling nanoparticle exposures. Journal of Nanoparticle Research, 2009.
11(7): p. 1685-1704.
3. National Institute for Occupational
Safety and Health, Approaches to safe nanotechnology: Managing the health and
safety concerns associated with engineered nanomaterials, Department of Health
and Human Services Centers for Disease Control and Prevention, Editor. 2009,
National Institute for Occupational Safety and Health.
Copyright AZoNano.com, Dr. Kristen M. Kulinowski (International
Council on Nanotechnology, Rice University)