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Science relating to Nanotechology, Endocrine Disrupters and Electromagnetic Radiation. Marion Palmer Lovells Science Unit. Overview. Nanotechnology Nanostructures & how nanotechnology works Applications Concerns and risks associated with nanotechnology Carbon nanotubes. Overview.
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Science relating to Nanotechology, Endocrine Disrupters and Electromagnetic Radiation Marion Palmer Lovells Science Unit Lovells LLP
Overview • Nanotechnology • Nanostructures & how nanotechnology works • Applications • Concerns and risks associated with nanotechnology • Carbon nanotubes
Overview • Endocrine Disrupters • Endocrine system and hormones • How endocrine disrupters work • Sources of potential endocrine disrupters • Concerns and risks associated with endocrine disrupters • TBT and DES
Overview • Electromagnetic Radiation • EMF spectrum • Electric and magnetic fields • Low frequency magnetic fields • Radiofrequency radiation
Nanotechnology Lovells LLP
Definition • No accepted definition at present • Nanoscience is the study of phenomena and manipulation of materials at atomic, molecular and macromolecular scales, where properties differ significantly from those at a larger scale. • Nanotechnologies are the design, characterisation, production and application of structures, devices and systems by controlling shape and size at nanometre scale.
5 mm 1mm Millimetre scale (1 m = 1000 mm)ant and flea http://www.nationalinsectweek.co.uk/resources/buzz_ant_06.pdf www.nanotec.org.uk/report/chapter2.pdf
400 µm 7 µm Micrometre scale (1 mm = 1000 µm)eye of a fruit fly and a red blood cell http://www.molbio1.princeton.edu/facility/confocal/sem/imagelist1.html www.mta.ca/dmf/blood.htm
50 – 100 nm 2 nm Nanometre scale (1 µm = 1000 nm) – viruses & DNA www.answers.com/topic/virus http://www.gala-instrumente.de/images/deben_CCD_DNA.jpg
Nanostructures • Nanoparticles
Nanostructures • Carbon nanotubes and buckyballs
Nanostructures • Quantum dots http://www.nist.gov/public_affairs/update/quantumdots.htm
Nanostructures • Non-carbon nanotubes • Nanowires • Biopolymers • Dendrimers http://www.nist.gov/public_affairs/05nano_image_gallery.htm http://nano.med.umich.edu/projects/dendrimers.html
How does nanotechnology work? • As objects get smaller they have a much greater surface area to volume ratio 2 cm cube has a surface area of 24 cm2 and a volume of 8 cm3 (ratio = 3) 10 cm cube has a surface area of 600 cm2 and a volume of 1000 cm3 (ratio = 0.6)
How does nanotechnology work? • At very small sizes quantum effects come into play which can result in changes to a particles magnetic, electric and optical properties. http://www.omicron.de/index2.html?/results/spin_polarized_tunneling_induced_luminescence_microcopy_sp_tilm/index.html~Omicron
Applications • Antibacterial effect of silver www.nanotech-now.com
Applications • Coatings - self-cleaning windows and stainproof clothing
Applications • Microchips • http://ion.asu.edu/cool66_IC2/cool66_ic_thumb.htm
Applications • Sun sunscreens and cosmetics
Catalysts Envirox™ cerium oxide Nanoremediation SAMMS technology to remove mercury Paper photographic paper Filters nanofibres Toothpaste to remineralise teeth Food packaging Paint improved adhesion and anti-fungal qualities/anti-graffiti Clothes non-staining and anti-radiation Batteries (Black & Decker) phosphate nanocrystal technology Cleaning products Applications
First Generation ~ 2001: Passive nanostructures Nano-structured coatings, nanoparticles, nanostructured metals, polymers, ceramics, catalysts, composites, displays Second Generation ~ Now: Active nanostructures Transistors, amplifiers, targeted drugs and chemicals, actuators, adaptive structures, sensors, diagnostic assays, fuel cells, solar cells, high performance nanocomposites, ceramics, metals Third Generation ~ 2010: 3-D nanosystems and systems of nanosystems Various assembly techniques, networking at the nanoscale and new architectures, Biomimetic materials, novel therapeutics/targeted drug delivery Fourth Generation ~ 2015: Molecular nanosystems Molecular devices “by design”, atomic design, emerging functions Future Applications
Why is there so much concern about nanotechnology • Currently not possible to detect most nanostructures without sophisticated equipment • Small size may result in greater dispersal than larger structures • Small size may result in particles passing into the body more easily (inhalation, ingestion, absorption) • May be more reactive due to surface area to volume ratio • May be processed differently by the body in comparison to larger structures • Greater potential to adsorb toxic chemicals • Persistence
Potentials risks associated with nanotechnology • Adverse health effects in humans from deliberate or accidental exposure • Adverse effects on the environment from deliberate or accidental exposure • Potentially explosive properties of nanostructures • “Grey goo” • Futuristic scenarios
Toxicological difficulties • No standardised terminology and method of measurement • All structures are likely to have a unique toxicological profile • Longevity of particles in the environment and body are unknown • Particle size may be less important than the surface characteristics of the material • Standard dose response may not be appropriate
Carbon nanotubes http://www.nano-lab.com/nanotube-image.html
Example – Carbon Nanotubes • Commercially produced by companies such as Thomas Swan • Very desirable product http://www.tennis.com/yourgame/gear/racquets/babolat/babolat.aspx?id=56932
Materials & Chemistry - Ceramic and metallic CNT composites - Polymer CNT composites (heat conducting polymers) - Coatings (e.g. conductive surfaces) - Membranes and catalysis Tips of Scanning Probe Microscopes (SPM) Medicine & Life Science - Medical diagnosis (e.g. Lab on a Chip (LOC)) - Medical applications (e.g. drug delivery) - Chemical sensors - Filters for water and food treatment Electronics & ICT - Lighting elements, CNT based field emission displays - Microelectronic: Single electron transistor - Molecular computing and data storage - Ultra-sensitive electromechanical sensors Micro-Electro-Mechanical Systems (MEMS) Energy - Hydrogen storage, energy storage (super capacitors) - Solar cells - Fuel cells - Superconductive materials Potential applications of carbon nanotubes
Carbon nanotubes • Have raised concerns due to a superficial likeness to asbestos fibres and extreme durability • Potential exposures during manufacturing, processing, product use and disposal • Have been researched more than most manufactured nanostructures
Research summary • Results have been variable dependent on dose, testing model, purity and type of nanostructure • Research results to date: • Some coated CNTs appear to move freely throughout the body (mice) whereas others are rapidly excreted • Installation experiments have shown inflammation and fibrosis • Inhalation experiments have shown small changes in the lung • Effects on the immune system • Effects on cell growth and death • Modification of tube coating by aquatic organisms