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NANOTECHNOLOGY: UNDERSTANDING
POTENTIAL RISKS AND THE ADOPTION OF PROACTIVE
PARADIGM
Water Research Commission Media Breakfast: Nanotechnology
15th March 2010, Venue: WRC offices - Pula boardroom, Pretoria, South Africa Ndeke Musee, CSIR ,Natural Resources and EnvironmentNatural Resources and
“A man would do nothing if he waited
until he could do it so well that no one would find fault with what he
had done.” Cardinal Newman
Soccer Ball22,64 cm
Nanoparticle, 4 nm
Earth12756 km
1,77 x 10-8 fold
2010 Soccer World Cup:
South Africa VIVA!88 Days To Go
PRESENTATION OUTLINE
SA government policy/strategy on
nanotechnology (Nano)
Why the need for risk assessment of
Nanotechnology?
Risk assessment challenges of Nanotechnology
presently
Development of risk assessment
tools/governance frameworks
South African Government Initiatives on Nano risk
assessment
Concluding remarks
Nanotechnology policies embedded on the National Systems of Innovation (NSI) plan/framework. NSI plan is central to SA’s prospects for continued economic growth and socioeconomic development
NSI is based on a series of strategic government documents since 1996 – see next page
SA Government goal of articulating a national path of innovation based on NSI in support of transforming the national resources based to knowledge-based economy through nanotechnology platform was implemented based on the National Nanotechnology Strategy (2004)
SA GOVERNMENT NANO POLICY/STRATEGY
SA GOVERNMENT NANO-RELATED POLICIES
White Paper on Science & Technology (1996)
National Research and Technology Foresight
(2000)
National Research and Development Strategy
(DST, 2002)
National nanotechnology strategy (DST, 2004)
Innovations towards a knowledge based
economy 2008–2018 plan (DST, 2009)
NATIONAL NANOTECHNOLOGY STRATEGY (2004) Set of strategic/tactical objectives
Support for long-term nanoscience research Support the creation of new and novel devices
for applications in various areas HCD and infrastructure development to allow
Nano growth Stimulate new developments in technology
missions for industrial applications Recommendations on the levels of funding
required Identification of the most critical areas of
concern (social and industrial clusters)
EXAMPLES OF CHALLENGES NANOTECHNOLOGY CAN ADDRESS
Poverty (economy, etc) Climate change Burden of disease (human health –
pathogens driven, occupational, pollution driven, environmental driven, etc)
Environmental protection … Energy
Training of future leaders in nanotechnology must concisely align in addressing part or all of
the challenges
NANOMATERIALS OF FOCI
Unintentional sources (natural and anthropogenic)
Intentional sources (anthropogenic)
χ√
UNIQUENESS OF MATERIALS AT NANO-SCALE
Materials reduced to the nano-scale can suddenly show novel properties compared to counterpart bulk materials, for example: Opaque substances become transparent
(copper); Stable materials become combustible
(aluminium); Inert materials become catalysts (platinum); Insulators become conductors (silicon); Solids turn into liquids at room temperature
(gold) Quantum effects become dominant which
potentially causes profound effects to biological receptor organisms
SOME EXAMPLES
20-90% atoms on surface, most dominant effects < 30 nm
Energy band increases with decrease in diameter (< 6 nm effects profound)
HISTORICAL MALEVOLENT TECHNOLOGIES
Dichlorodiphenyltrichloroethane (DDT)
Asbestos (asbestosis disease)
Chlorofluorocarbons (CFS)
Genetically modified organisms (GMOs)
Cell research
Mining (silicosis-related ailments)
Nuclear Industry (nuclear waste management nightmare)
Radiation
MBDT/TBT
Benzene
Space programme
DEFINING HAZARD & EXPOSURE
Hazard – has numerous definitions. Here, the United States Environmental Protection Agency (EPA) definition is adopted:
Hazard is the inherent toxicity of a compound
Exposure is the probability of a hazardous substance to become bioavailable to the receptor organisms
DEFINING RISK
EPA defines risk as a measure of the
probability that damage to life, health,
property, and/or the environment will occur
as a result of a given hazard
If the probability of an exposure to a
hazardous material is high and the
consequences for the health or environment
are significant, then the risk is considered to
be high
BASIC PREMISE OF RISK ASSESSMENT
Hazard X Exposure = Risk
Hazard =0; Risk = 0
Exposure = 0; Risk = 0
Recommended approach: Minimize hazard
and/or exposure
TYPES OF RISKS
Known Risks Cause and effects known Responsibility can be generally attributed &
prevention developed Most macroscale risks known and preventable
Unknown Risks – “Potential Risks” Causality of cause and effects/damage not well
known Thus; danger is unclear Degree of damage/danger not well quantifiable Significance of probability of occurrence unknown Evokes suspicion/perceived risks Applies in case of nanotechnologies both in humans &
the environment
EXAMPLES OF RISK ASSESSMENT CHALLENGES (1)
Large diversity of ENMs generated (oxides, metals, carbon-based, QDs, etc) and products/applications (electronics, personal care, drugs, etc)
Dynamic transformation of NMs throughout their entire lifecycle Strong influence on fate and behaviour of NMs
in different macro-environmental systems (pH, salinity, presence or absence of oxidants, zeta potential, effects of macromolecules, presence of macroscale chemicals, indigestion by organisms, methods of production, stability of coating, etc)
Lack of metrology: how easy is it to detect NMs in soils and water systems? (“out of phase effect”) – risk assessment capabilities currently tailing technological advancement
Legislative inertia: Save Berkeley City, USA, Canada, EU (globally) Toxic substances control Act (TSCA) Federal Food, Drug, and Cosmetic Act (FFDCA) European Union Directives (“incremental approach”) Mass per volume toxicity measurement (unit) inadequate
Absence of exposure data Do they partition in the environment? Half-lives unknown Bioaccumulation, biopersistence, biomagnification data
yet to be generated
EXAMPLES OF RISK ASSESSMENT CHALLENGES (2)
No single index for measuring the toxicity of nanomaterials Surface area, particle number, volume, etc
Limited toxicity data Limited acute toxicity data (no clear link between
observed toxicity and physicochemical properties) Almost none chronic data of NMs has been
published Most data available based on laboratory
environments (see reviews of Borm et al., 2006; Handy et al., 2008)
Inconsistence of data (comparison of toxicity for TiO2 Velzeboer et al., 2008 and Lovern and Klopper, 2006 differ significantly)
EXAMPLES OF RISK ASSESSMENT CHALLENGES (3)
Limitations of risk assessment methodologies, for example: Uncertainty in applying standardized tests previously
developed for macroscale chemicals Uncertainty in characterisation of ENMs in test systems Difficulties in detecting and quantifying ENMs in
complex environmental matrices Uncertainty in sample preparations for
nanoecotoxicology studies
EXAMPLES OF RISK ASSESSMENT CHALLENGES (4)
LIMITED DATA TO SUPPORT DECISION MAKING
Grieger et al, 2010:Redefining risk research priorities for nanomaterials, J Nanoparticle Research (2010) 12:383–392
Aspects of serious concerns
FIVE GRAND CHALLENGES OF ENMS RISK ASSESSMENT
Maynard et al., 2006. Safe Handling of Nanomaterials. Nature 444 (11):267–269.
RISK ASSESSMENT TOOLS/GOVERNANCE FRAMEWORKS
Not yet in South Africa
European Union
United States of America
Japan
REGULATORY FRAMEWORK
Limitations of the current legislative frameworks for ENMs, viz.: Current regulatory programs, standards and
related exceptions based on mass to mass conc. Yet, other factors e.g. surface area, enhanced surface activity, etc likely to cause advance effects at lower concentrations
Lack of predictive models of NMs toxicity based on previously known toxicity of other ENMs or bulk conventional counterpart chemicals
Highly dispersed production facilities – numerous small and medium sized companies – hinders coherent data collection – wide diversity of applications – lack of expertise on legislative compliance
REGULATORY FRAMEWORK… Cont.
High speed of nanotechnology development outpaces the legislative framework evolution – takes long period of time to conclude. Thus, to date no clear occupational and environmental laws
Breadth of applications will fall under the cracks of legislative frameworks – as some applications of ENMs in products and services are outside legislative frameworks (e.g. household products, etc)
EXAMPLES HIGHER ENMS TOXICITY
ENMs of CuO are up to 50-FOLD more toxic than particles of bulk CuO towards crustaceans (Heinlaan et al., 2008), algae, (Aruoja et al., 2009), protozoa (Mortimer et al., 2009, this issue) and yeast (Kasemets et al., 2009)
TiO2 and Al2O3 ENMs are about TWICE more toxic than their respective bulk formulations towards nematodes (Wang et al., 2009).
Ag ENMS of about 5 nm sizes were more toxic to bacteria than any other fractions of NPs or their bulk species (Choi and Hu, 2008).
SA GOVERNMENT CURRENT INITIATIVES
Setting up of a Environmental, Safety and Health Research Platform, comprise of: Human capital development (HCD) Focussed research Development of infrastructure Database for HSE aspects related to
nanotechnology Establishment of national nanotechnology
ethics committee Initiation of international research
collaborations
NANOTECHNOLOGY RISK CONCERNS IN SOUTH AFRICA
Web link: http://intraweb.csir.co.za/news/inthenews/2009/TheStar_Nanotech.pdf
Example 1
• •
Star, February 16, 2009• Questions on potential risks
were explicitly raised by the media
• Link of CNTs and asbestos health effects on lungs were inferred
• Robots replacing humans and getting out of control
• Unethical aspects related to nanotechnology were raised
• •
Sunday Times, May 25, 2008• CNTs link to health risks
similar to asbestos suggested
• Current researchers’ findings reported in Journal of Nature supports this view
• Not yet single case of disease has been reported associated with CNTs
• Cautionary approach was proposed
• Risk health effects postulated after the products lifespan
• Greatest risk for workers in research labs and manufacturing sector were raised
Example 2
RISK COMMUNICATION…
Risk communication is critical in enabling public engagement with new technologies (balancing of technology benefits versus risks)
Forms the cornerstone of opinion-forming process on the public acceptance/debate regarding a given technology – has a lasting mark on the development of technologies and their applications
Should reflect current and dynamic social, scientific, and political imperatives
For nanotechnologies – its promises and potential public fears needs to be taken into account, and addressed expeditiously
Requires an on-going debates among different stakeholders to ascertain opportunities and risks (government, industry and the public)
But who remains the most suitable to communicate technology risks?
BENEFITS OF RISK COMMUNICATION…
Increased awareness and understanding of the nanosafety implications for the nanobioscience industry
Ensure future workforce at any level and sector understands the HSE implications for the business sustainability (marketing and customer relationships)
Promote nanobioscience industry’s environmental stewardship and societal responsibility
Training of candidates the emerging protocols in nanotoxicology and nanoecotoxicology
Contribute in the field of risk assessment for nanomaterials with respect to: Standardization Establish occupational threshold limits Meeting and/or setting of regulatory
requirements for nanoscale materials in products and industrial products
RESPONSE TO ADDRESS PRIORITY NEEDS
Ensure sufficient skills are available
Deploy the required technologies
Possess (and use) the necessary equipment
effectively
Obtain sufficient financial support
Be supported by the required legal
instruments (laws) and standards