Nanotechnology and Health: Is Nano Safe?. Seán Barry, Carleton University. The Scale of “Nanoscale”. 1 – 100 nm 1x10 -9 – 1x10 -7 m across Canada → a centimetre. What Nanotechnology is Not.
1 – 100 nm 1x10-9 – 1x10-7 m
across Canada → a centimetre
Investments in nanotechnology are on the rise.
These advances are in both basic university-basedresearch, as well as industry.
Many of these advances use nanoparticles in some form or other.
Recording heads are miniature (about 1mm2) and read and write information to and from a hard-drive disk or another storage medium.
They have a “supermagnetic” layer that is nanometres thick. (typically Ni80Fe20, Ni45Fe55 or “FeAlN”)
Adapted from J. Nanosci. Nanotechnol.2007, 7, 3048.
To use nanoparticles in vivo, one often selects polymers known to be non-toxic. Polyglycolic-lactic acid (PGLA) is a good example.
Nanoparticles of this materialcan be dosed with specifictherapeutic agents and injectedinto biological systems.
Drug release from a nanoparticle is slow and steady over time.
PNAS 2006, 103(16), 6315.
PNAS 2006, 103(16), 6315.
Specific uptake occurs when a nanoparticle has surface “chemistry” that binds to specific sites on the cell walls.
Mostly, this is engineered.
Nature Mater.2009, 8, 543.
Non-specific uptakeis due to the characteristics of thenanoparticle, but will be taken up by any cell wall.
This is a general toxicity.
Nature Mater.2009, 8, 543.
The toxicity, like many properties of nanomaterials, differ from their macroscale characteristics.
J. Nanosci. Nanotechnol.2007, 7, 3048.
Superparamagnetic iron oxide (SPION) was shown to enhance medical magnetic imaging.
However, normal SPION is toxic.
When coated with a sugar derivative (Pullulan), it was found to be non-toxic.
Cells incubated with iron oxide nanoparticles.
Cells incubated with pullulan-coated iron oxide nanoparticles.
There is presently debate about whether they have health risks akin to asbestos:
“Our data demonstrate that asbestos-like pathogenic behaviour associated with CNTs conforms to a structure–activity relationship based on length, to which asbestos and other pathogenic ﬁbres conform.” Nature Nano. 2008,3, 423.
“The recent findings are quite specific for this particular subclass of long, unfunctionalized MWNTs and it is difficult to extrapolate to other nanotube types.” Nature Nano. 2008,3, 378.
Policy and Science interconnect on many planes, and nanoscience is becoming one of them.
An excellent summary of the different responses of governments to nanoscience regulation has been compiled by Jennifer Pelley and Marc Saner.
The U.S.A. is investing $1.5 billion in nanoscience in 2009. This includes the responsible development of nanoscience, but no Federal regulation yet exists.
“Existing statutory authorities are adequate to address oversight of nanotechnology and its applications.”
“Where possible, regulatory approaches should enable rather than hinder innovation…”
“Benefits of regulation should justify their costs.”
Joint memorandum by the Director of the Office of Science and Technology Policy and the Chairman of the Council on Environmental Quality
The Environmental Protection Agency issued a White Paper, and has a voluntary “Nanoscale Materials Stewardship Program”
The Food and Drug Administration have a task force, but feel that existing regulations can govern nanomaterials.
California and Massachusetts both have State and Municipal regulations of nano health and safety.
The European Union is more inclined to precaution.
“Where the full extent of a risk is unknown, but concerns are so high that risk management measures are considered necessary,…measures must be based on the Precautionary Principle”
“The regulatory challenge is therefore to ensure that society can benefit from novel applications of nanotechnology, whilst a high level of protection of health, safety and the environment is
The European Commission Regulatory Aspects of Nanomaterials.
The Registration, Evaluation, Authorisation and Restriction of Chemical Substances (REACH) regulation has no specific statement on nano materials, except to differentiate carbon nanotubes from bulk carbon.
The “Cosmetics Directive” and “Novel Food Regulation” both mention specific assessment for nanomaterials, defining such as having one or more dimension on the scale of 1 to 100 nm.
Canada adopted a mediated outlook in 2007:
“…strong science and effective regulation to protect human health and the environment while supporting Canadian competitiveness.”
“…an effective, forward-looking, and responsive regulatory environment that promotes a competitive marketplace and protects the health and safety of Canadians and the environment.”
Government of Canada, Comprehensive Science & Technology (S&T) Strategy: Mobilizing Science & Technology to Canada‟s Advantage
Canada is focused on international cooperation, but has made some regulatory changes:
Canadian Environmental Protection Act 1999 governs “new” material and its regulation in Canada. Environment Canada issued an advisory note in 2007 stating that it considered a material new if it “possesses unique structures or molecular arrangements” and proposed an amendment to the Act.
This covers nanomaterials, and was included specifically for nanotubes.