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									By Stanley Lam and Madelaine Doe
   “Nanotechnology could prove to be a
transformative technology comparable in its
   impact to the steam engine in the 18th
 century, electricity in the 20th century, and
   the Internet in contemporary society.”
What are Nanoparticles?
 Structures 100 nanometers or smaller
   Carbon Nanotubes, Fullerenes, TiO2, Nanogold, ect.

 Surface area to volume ratio dramatically
  increased
 Electrons forced into condensed space
 Different properties on the nanoscale
Applications of Nanomaterials
• Nano-applications are radically transforming a host
 of products and services, including:
  – battery-storage capacity
  – computer-chip minimization
  – drug delivery
  – cosmetics
  – food packaging
  – solar energy
  – water purification
Nanomaterials are Everywhere
 Nanotechnology growing at an unprecedented rate.
 Predicted to have a trillion dollar impact and employ
  2 million workers worldwide by 2015.
 More than 800 products already being sold to
  Canadian consumers.
Ways we are Exposed
 Through consumer products


 Medical treatment


 Environmental contamination


 Workplace exposure
Occupational Exposure
 Currently regulations based on ultrafine particles
    Unclear to what extent analogies can be drawn
         Carbon nanotubes characterized as graphite

 Sampling methods available are insufficient

 Biggest risk includes inhalation and dermal contact

 Unclear whether protective equipment is adequate
    Risk during cleaning and repair of equipment
Nanoparticles in various forms
Modes of entry and Routes of Distribution




                           (Oberdorster et. al., 2005)
The most likely mode of entry is the
Respiratory Tract
 Olfactory
  Epithelium
 Upper
  Respiratory
  Tract
 Lower
  Respiratory
  Tract



                            (Oberdorster et. al., 2005)
Nanoparticles Cross Alveolar Epithelium
Effects on Organs: Mice Kidney and Spleen


                          Mice kidney




                          Mice spleen
(Buzea C et. al., 2007)
What are the effects, if any, at
the cellular level?
Gold Nanorods taken up by
cells




                     (Kuo CW et. al., 2007)
Carbon Nanotubes are Harmful to cells
 Human Cell Lines
   Altered cell architecture
   Diminished proliferation and apoptosis
   Generation of free radicals and oxidative species
 Animal Studies
   Granuloma formation, atherosclerosis, mitochondrial
     DNA damage                                              (Kostarelo et. al., 2007)



   Endothelial cells
   (A549)




   Mesothelioma
   cells
   (MSTO-211H)

                                                          (Kaiser JP et. al., 2007)
    Generation of ROS by TiO2 in cultured Human
    Bronchial Epithelial Cells

Dose Dependence




TiO2 Localization




 Time Course




                                           (Park EJ et. al., 2007)
Fullerenes are Harmful to cells
 Human Cell Lines
   Uptake of C60 causes membrane leakage
   Increased ROS production and DNA damage
   Decreased cell growth (no apoptosis)
 Animal Studies
   Elevated lipid oxidation levels in brains of fish, 100%
    mortality in fathead minnows (when coupled with THF)




              (Porter AE et. al., 2007)          (Wong-Ekkabut J et. al., 2008)
Environmental Interactions




                    (Oberdorster et. al., 2005)
Environmental Issues
 Good information is scarce
 No single index to measure and toxicity
 Nanoparticles are not easily detected and monitored
  in real time
 Increased environmental transport
 Environmental fate unknown.
There are 3 main Factors
predicting environmental
behaviour
1) Potential and rate of dispersal or agglomeration in
   environmental media.
2) Potential and rate of interactions with
   environmental constituents.
3) Rate and form that a nanomaterial will be
   presented to the environment.
Detection Methods
 Scanning Mobility Particle Sizer (SMPS)
 Optical Chromophore Counting
 Resonant Light Scattering
 Scanning Transmission Electron Microscopy (STEM)
 High Resolution Transmission Electron Microscopy
 (HRTEM).
Canadian Nano-Regulations
• In Canada no nanomaterial-specific regulations or a
 list of nanomaterials that have been developed

• Currently using the existing legislative and
 regulatory frameworks based on ultrafine particles

• A panel of 15 nanotechnology experts warned the
 Canadian federal government action is "urgently"
 needed to assess the potential risks
Around the Globe
 Last month the U. S. National Research Council blasted
 Washington for not adequately dealing with the
 environmental, health and safety impacts of
 nanomaterials

• In Great Britain, the Royal Commission on
 Environmental Pollution issued a report that said, while
 there is no evidence nanomaterials have harmed people
 or the environment, more research is needed to assess
 their safety.

• The EU and Australia have been given similar warnings
What the World Needs
 To create a special regulatory classification and
  standard testing regimens for nanomaterials
 A regulatory system which doesn’t hobble
  research and the development of new products
 Put more money into funding, specifically into the
  effects on human health and the environment
Into the future...
 Promising field
 Potentials in
   Medical care
   Water filtration
   Faster and smarter computers
 Research into risk assessment is crucial
Thanks for listening…
References
   Buzea C, Pacheco I, and Robbie K. (2006) Nanomaterials and nanoparticles: Sources and toxicity.
    Biointerphases. Vol.2:4:MR17-MR71.

   Kaiser JP et. al. (2007) Single walled carbon nanotubes (SWCNT) affect cell physiology and cell
    architecture. J Mater Sci: Mater Med Vol.19:1523–1527.

   Kostarelos K et. al.. (2007) Cellular uptake of functionalized carbon nanotubes is independent of
    functional group and cell type. Nature Nanotechnology. Vol.2:108-113.

   Kuo CW et. al. (2007) Studies of Surface-Modified Gold Nanowires Inside Living Cells. Advanced
    Functional Materials. Vol.17, 3707–3714.

   Oberdörster G, Oberdörster E, and Oberdörster E. (2005) Nanotoxicology: An Emerging
    Discipline Evolving from Studies of Ultrafine Particles. Environmental Health Perspectives.
    Vol.113:7:823-839.


   Park EJ et. al. (2008) Oxidative stress induced by cerium oxide nanoparticles in cultured BEAS-2B
    cells. Toxicology. 245:90–100

   Porter AE et. al. (2007) Visualizing the Uptake of C60 to the Cytoplasm and Nucleus of Human
    Monocyte-Derived Macrophage Cells Using Energy-Filtered Transmission Electron Microscopy
    and Electron Tomography. Environ. Sci. Technol. Vol.41, 3012-3017.

   Wong-Ekkabut J et. al. (2008) Computer simulation study of fullerene translocation through lipid
    membranes. Nature Nanotechnology. Vol.3:363-368.

								
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