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NANOTECHNOLOGY: UNDERSTANDING POTENTIAL RISKS AND THE ADOPTION OF PROACTIVE PARADIGM. 15 th March 2010, Venue: WRC offices - Pula boardroom, Pretoria, South Africa. Water Research Commission Media Breakfast: Nanotechnology.
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NANOTECHNOLOGY: UNDERSTANDING POTENTIAL RISKS AND THE ADOPTION OF PROACTIVE PARADIGM 15th March 2010, Venue: WRC offices - Pula boardroom, Pretoria, South Africa Water Research Commission Media Breakfast: Nanotechnology
“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
2010 Soccer World Cup: South Africa VIVA! 88 Days To Go Earth 12756 km 1,77 x 10-8 fold Soccer Ball 22,64 cm Nanoparticle, 4 nm
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
South Africa Government Nanotechnology Underlying Policies and Strategies
SA GOVERNMENT NANO POLICY/STRATEGY • 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-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
Why Risk Assessment Now for Engineered Nanomaterials Materials (ENMs)?
Intentional sources (anthropogenic) Unintentional sources (natural and anthropogenic) √ χ NANOMATERIALS OF FOCI
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 • Mining (silicosis-related ailments) • Nuclear Industry (nuclear waste management nightmare) • Radiation • MBDT/TBT • Benzene • Space programme • Dichlorodiphenyltrichloroethane (DDT) • Asbestos (asbestosis disease) • Chlorofluorocarbons (CFS) • Genetically modified organisms (GMOs) • Cell research
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
EXAMPLES OF RISK ASSESSMENT CHALLENGES (2) • 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 (3) • 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 (4) • 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
LIMITED DATA TO SUPPORT DECISION MAKING Aspects of serious concerns Grieger et al, 2010:Redefining risk research priorities for nanomaterials, J Nanoparticle Research (2010) 12:383–392
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 • 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 Example 1 Web link: http://intraweb.csir.co.za/news/inthenews/2009/TheStar_Nanotech.pdf
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
ACKNOWLEDGEMENTS • CSIR • DST • WRC