Bao cao nano silver ppt

Nano Silver Neena Sahasrabudhe DTSC Nano Material Applications • CONSUMER PRODUCTS • PESTICIDES AND ANTIMICROBIALS • MEDICAL DIAGNOSTICS AND PHARMACEUTICALS • BIOTECHNOLOGY • AUTOMOTIVE • PAINTS AND COATINGS • COSMETICS AND PERSONAL CARE • ENERGY AND ELECTRONICS • WATER AND WASTE TREATMENT Nano silver uses • Medical Products—wound dressings, surgical gauze, bandages • Textiles and Clothing • Sporting Goods • Aerospace and Electronics Why are nano materials popular? • Different Physical and Chemical properties • Anti-bacterial and anti-fungal properties • Light weight • Enhanced product performance Nano materials also used in • Environmental Remediation • Decontamination of Pollutants Environmental Health and Safety Concerns of Nano Silver • Potential to be released into environment • May be toxic to beneficial microbes • Impact on aquatic species Nano Material Lifecycle Processes Systems Integration Devices Manufacture Transportation Materials Storage Waste Release Disposal Facility Consumer Products Workers Consumers / Public Air Food Ocean Soil/ Sediment Water Environment Plant Animal ‘I-on’ concern • Ag (metal) Ag + e- • Silver ions (Ag+) were considered the culprit behind the toxicity of silver nano particles (AgNP*) * AgNP- Silver nano particles Wastewater treatment concerns “Considering the current extensive production of Ag NPs and their widespread use in consumer products, it is likely that they are entering wastewater streams and the treatment facilities that process this water”** • nano silver in products can affect the good bacteria in treatment plants • Treatment plants may not function to its capacity **Discovery and Characterization of Silver Sulfide Nanoparticles in Final Sewage Sludge Products Kim , Park, Murayama and Hochella, The Center for NanoBioEarth, Department of Geosciences,Virginia Tech, Department of Materials Science and Engineering From consumer uses May affect solids treatment and energy processes? May affect treatment process? May affect receiving water and biota? 10 Other Concerns • • • • Other consumer products lined with antibacterial nano silver Food containers, baby bottles Band aids Medicinal supplements • FDA nanotechnology section • DTSC does not cover all consumer products 11 Is human population affected? • Silver metal in colloidal form has been used as anti-bacterial from ancient times • Engineered nano silver differs from silver metal • Definitive research on nano silver and in vivo studies for mammals is unknown • Research at UCLA plans to find out IF silver nano plates are toxic to mammalian lungs if inhaled 12 What we know and not know • Nano material obtained by the manufacturer • Manufacturer may know the modification of nanomaterial into the product • What is coming out of product into the environment IS UNKNOWN 13 Data gaps Fate, Transport, Toxicity and ANALYTICAL METHODS unknown 14 Nano Silver in Environment • Lake Ecosystem Nano Silver ( LENS) Project* • Effect of nano silver on aquatic environment • Will monitor changes in lake’s ecosystem • Track effects through entire food web • Determine how resulting changes alter ecosystem function * Trent University- Natural Sciences and Engineering Research Council of Canada, Environmental Canada Support- Fisheries and Oceans Canada 15 Measurement Techniques Transmission Electron Microscopy (TEM) Scanning Electron Microscopy (SEM) X- Ray Diffraction (XRD) Atomic Force Microscopy (AFM) Measurement*** of silver nano particles also depends on Agglomeration/ thickness of initial capping agents Dispersion conditions/thickness of natural organic molecules (NOM) ***Challenges for physical characterization of silver nano particles under pristine and environmentally relevant conditions Robert Mac Cuspie et al, J Environ Monit.,2011 16 Shape affects Toxicity • Silver nano plates are toxic in direct contact with cells of some fish* • Silver nano spheres are toxic in high concentration • Silver nano wires are much less toxic • * Rainbow Trout and Zebra fish** • ** nanotechweb- research at UCLA, DR.A Nel, S George et al 17 DTSC and Nanosilver Round Two call-in dataset –identified: Twelve (12) nano silver manufacturers or importers Requested information from manufacturers and importers on analytical methods of their chemical 18 19 Outcomes 1.Cooperation and communications with creators and user's of the material 2.MOU with other state agency (DPR*) Collaboration with Federal agencies, Universities, research agencies Other participations Nano toolkit *DPR- Department of Pesticide Regulations( Cal EPA) 20 Thank you Neena Sahasrabudhe, Ph.D 916/324 8660 nsahasra@dtsc.ca.gov 21 ... • Engineered nano silver differs from silver metal • Definitive research on nano silver and in vivo studies for mammals is unknown • Research at UCLA plans to find out IF silver nano plates are... Transport, Toxicity and ANALYTICAL METHODS unknown 14 Nano Silver in Environment • Lake Ecosystem Nano Silver ( LENS) Project* • Effect of nano silver on aquatic environment • Will monitor changes... ‘I-on’ concern • Ag (metal) Ag + e- • Silver ions (Ag+) were considered the culprit behind the toxicity of silver nano particles (AgNP*) * AgNP- Silver nano particles Wastewater treatment concerns