Nanotechnology: Environment, Health, and Safety

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Nanotechnology Environment, Health, and Safety

• Clark A. Miller, PhD
• Associate Director for Education and Outreach
• Center for Nanotechnology in Society
• Arizona State University
• http//cns.asu.edu/index.htm
• June 6, 2008

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Objectives

• What is nanotechnology?
• Why is nanotechnology so exciting?
• What are emerging product areas?
• Are there risks associated with nanotechnology?
• What guidelines exist for nanotechnology EHS
  protection?
• Where can resources be found about nanotechnology
  EHS?

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What is nanotechnology?

• Nanotechnology is defined as the ability to
  visualize, analyze, and manipulate materials on
  molecular scales of approximately 0.1 to 100 nm.
• By 2015, the National Science Foundation
  estimates that nanotechnology will have a 1
  trillion impact on the global economy and will
  employ 2 million workers, 1 million of which may
  be in the United States (Roco and Bainbridge
  2001).
• Estimates of the market for carbon nanotubes are
  1-2 billion by 2015 (Thayer 2007).
• Nanotechnology is a broad classification that
  includes a wide range of applications across a
  wide range of technology platforms, including
  scanning, tunneling, and atomic force microscopy,
  next generation semiconductors, nanoparticles,
  nano-bio molecules, thin film technologies,
  nano-sensors and other nano-devices, quantum
  dots, quantum computing, and many, many more.

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Scaling matter
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What is nanotechnology?
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Go Sun Devils!
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Why nanotechnology?

• Properties of materials change dramatically at
  nanoscales. For example
• Color Gold nanoparticles in suspension are red
• Friction Oils, on nanoscales, are made up of
  large molecules that can obstruct motion of
  physical systems frictional forces dominate in
  many phycial systems
• Domain Light and electrons follow quantum rather
  than classical dynamics

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Nano Products

• The Woodrow Wilson Project on Emerging
  Nanotechnologies identifies over 600 existing
  consumer products that incorporate nanotechnology
• Vast majority involve nanoparticles sunscreens,
  paints, cleaners, coatings, protective sprays,
  clothing, detergents, air purifiers, food,
  kitchen utensils, cooking oil, food storage
  containers, cooking pans, baby bottles,
  nutritional supplements, cosmetics, sports
  equipment, filtration equipment, wood sealants,
  glass sealants, sandable glue, etc.
• Others are predominantly nanostructured
  electronics semiconductor chips, hard drives,
  etc.

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Nanoparticle safety research highlights

• EPA has concluded that ultrafine particulates,
  which are defined as less than 100nm, are a known
  health hazard at existing NAAQS standards.
• A growing body of research evidence suggests that
  exposure to engineered nanoparticles can also
  lead to toxicological effects, especially when
  breathed in through the lungs. Other exposure
  pathways have been less studied with mixed
  results.
• Few, if any, life cycle studies have been done on
  nano-based products to determine whether
  exposures to nanoparticles can occur during
  production, use, or disposal of products.
• Disposal of molecular compounds (such as
  pharmaceutical drugs) is known to have
  contaminated water supplies whether disposal of
  household products with nanoparticles will behave
  similarly is not known, nor is the environmental
  or health impact.
• Toxicology data on macro-scale materials may or
  may not be relevant to understanding the
  toxicology of nano-scale materials. Properties
  change.
• In general, considerable uncertainties exist in
  our current understanding of environmental and
  health consequences of nanoparticles and other
  nanotechnologies. But, there are good reasons to
  believe that some forms of toxicity will emerge.
• My view is that we should be careful and assume
  an elevated safety posture.

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Nanoparticle safety research a few examples

• Ultrafine particulate matter, which EPA defines
  as particulates less than 100nm in size, is a
  known health hazard from considerable research
  sponsored by EPA and other government agencies.
• http//www.epa.gov/NHEERL/research/pm/index.html
• Ultrafine particles are estimated to cause
  100,000 deaths per year in the US (Schwartz et
  al. 2002)
• The comparability of engineered NPs to UFPs
  suggests that the human health effects are likely
  to be similar. Therefore, it is prudent to
  elucidate their toxicologic effect to minimize
  occupational and environmental exposure. (Gwynn
  and Vallyathan 2006)
• Elder et al (2006) observe that the carbon
  nanoparticles enter the brain by moving down the
  brain cells that pick up odours and transmit
  signals to the olfactory bulb.

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Nanoparticle safety research a few examples

• Studies have shown that fullerene (C60) molecules
  in solution cause peroxidation of lipids in the
  brains of aquatic species and have significant
  detrimental effects on the development and
  reproduction of aquatic species (Oberdorster
  2004 Oberdorster et al. 2006)
• http//www.ehponline.org/members/2004/7021/7021.ht
  ml
• http//dx.doi.org/10.1016/j.carbon.2005.11.008

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Nanoparticle safety research a few examples

• Recent studies on mice have identified that long
  carbon nanotubes that look like asbestos fibers
  cause similar pathological precursors to lung
  cancer as asbestos (Poland et al. 2008
  http//www.nanotechproject.org/news/archive/mwcnt/
  http//www.nature.com/nnano/journal/vaop/ncurren
  t/abs/nnano.2008.111.html)
• Exposing the mesothelial lining of the body
  cavity of mice, as a surrogate for the
  mesothelial lining of the chest cavity, to long
  multiwalled carbon nanotubes results in
  asbestos-like, length-dependent, pathogenic
  behaviour. This includes inflammation and the
  formation of lesions known as granulomas. This is
  of considerable importance, because research and
  business communities continue to invest heavily
  in carbon nanotubes for a wide range of products5
  under the assumption that they are no more
  hazardous than graphite. Our results suggest the
  need for further research and great caution
  before introducing such products into the market
  if long-term harm is to be avoided.

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Nanosafety guidelines

• From NIOSH report Approaches to Safe
  Nanotechnology (2006).
• Many uncertainties exist regarding occupational
  risks from engineered nanotechnologies
• Material safety data sheets for bulk materials
  may not be accurate for the same material in the
  form of nanoparticles
• Current scientific evidence indicates that
  nanoparticles may be more biologically reactive
  than larger particles of similar chemical
  composition and thus may pose a greater health
  risk when inhaled.
• Particle shape and surface area may be more
  important than mass in determining toxicity
• Quantum dots have been shown to penetrate the
  skin ingestion can also be an exposure route
• Other safety concerns can include fire and
  explosion (especially for nanoparticle powders)
  and catalytic reaction
• A range of possible workshop exposure pathways
  should be investigated and mitigated using
  standard chemical and material safety practices
  (gloves, masks, hoods, HEPA filters, etc.)

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Nanosafety guidelines

• From NIOSH report Approaches to Safe
  Nanotechnology (2006).
• Until further information on the possible health
  risks and extent of occupational exposure to
  nanomaterials becomes available, interim
  precautionary measures should be developed and
  implemented.
• In the absence of specific exposure limits or
  guidelines for engineered nanoparticles, exposure
  data gathered from the use of respirable samplers
  NIOSH 1994b can be used to determine the need
  for engineering controls or work practices and
  for routine exposure monitoring of processes and
  job tasks.
• For most processes and job tasks, the control of
  airborne exposure to nanoparticles can most
  likely be accomplished using a wide variety of
  engineering control techniques similar to those
  used in reducing exposures to general aerosols.
• Current knowledge indicates that a well-designed
  exhaust ventilation system with a high-efficiency
  particulate air (HEPA) filter should effectively
  remove nanoparticles.
• Every workplace dealing with nanoparticles,
  engineered nanomaterials, or other aspects of
  nanotechnology should consider the need for an
  occupational health surveillance program.

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Resources for Nano Risk Information

• NIOSH Nanotechnology Information
  http//www.cdc.gov/niosh/topics/nanotech/
• EPA Nanotechnology Information http//www.epa.gov/
  oppt/nano/
• FDA Nanotechnology Information http//www.fda.gov/
  nanotechnology/
• Woodrow Wilson Institute Project on Emerging
  Nanotechnologies http//www.nanotechproject.org/
• UW Madison Nano Risk Resources http//www.nsec.wis
  c.edu/NanoRisks/NS--NanoRisks.php
• UK Safe Nano Project http//www.safenano.org/
• ICON http//icon.rice.edu/resources.cfm

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Measurement

• You can collect nanoparticles with filters, but
  you probably cant detect them.
• Condensation particle counters (6K - 20K) size
  range 2 to 1000nm
• Other technologies such as low pressure impactors
  and SMPS relatively expensive
• Combustion aerosols

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Controls

• http//www.cdc.gov/niosh/topics/nanotech/
• Control Banding
• Ad Hoc exposure limits
• Pharmaceutical Model

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Respiratory Protection

• Expect conventional technology to be effective
• Watch for dirty jobs (cleaning reactors and
  equipment)

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ASU EHS Planning

• Communicate concerns to Research Community
• Sponsor seminars
• Modify CHP with nano guidance
• Educate staff to better support labs