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Nano SilverNeena SahasrabudheDTSC

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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 TREATMENT2


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Nano silver uses

Medical Productswound dressings,

surgical gauze, bandages

Textiles and Clothing

Sporting Goods

Aerospace and Electronics

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Why are nano materials popular?

Different Physical and Chemicalproperties

Anti-bacterial and anti-fungal properties

Light weight

Enhanced product performance 4


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Nano materials also used in

Environmental Remediation

Decontamination of Pollutants

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Environmental Health and Safety

Concerns of Nano Silver

Potential to be released into environment

May be toxic to beneficial microbes

Impact on aquatic species

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Nano Material Lifecycle

Manufacture Transportation Storage

Consumers /

Public

Materials

WorkersWaste

Soil/

SedimentWater

Air Ocean

Plant

Animal

Food

Environment

Integration

Consumer

Products

Devices

Processes

Facility

Systems

Release

Disposal

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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 8


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Wastewater treatment concerns

Considering the current extensive production of Ag NPs andtheir 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 intreatment plants

Treatment plants may not function to its capacity

**Discovery and Characterization of Silver Sulfide Nanoparticles in Final Sewage Sludge ProductsKim , Park, Murayama and Hochella, The Center for NanoBioEarth, Department ofGeosciences,Virginia Tech, Department of Materials Science and Engineering

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From

consumer uses

May

affect

treatmentprocess?

May

affect solids

treatmentand energy

processes?

May

affectreceiving

water

and biota?

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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


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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 vivostudies for mammals is unknown

Research at UCLA plans to find out IF silver nano

plates are toxic to mammalian lungs if inhaled

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What we know

and do not know

Nano material obtained by the

manufacturerManufacturer may know the modification

of nanomaterial into the product

What is coming out of product into theenvironment IS UNKNOWN

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Data gaps

Fate, Transport, Toxicity and ANALYTICAL

METHODS unknown

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Nano Silver in Environment

Lake Ecosystem Nano Silver ( LENS) Project*

Effect of nano silver on aquatic environment

Will monitor changes in lakes 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

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Measurement Techniques

Transmission Electron Microscopy (TEM)Scanning Electron Microscopy (SEM)

X- Ray Diffraction (XRD)

Atomic Force Microscopy (AFM)

Measurement*** of silver nano particles also dependson

Agglomeration/ thickness of initial capping agents

Dispersion conditions/thickness of natural organicmolecules (NOM)

***Challenges for physical characterization of silver nano particles underpristine and environmentally relevant conditions

Robert Mac Cuspie et al, J. Environ. Monit.,201116


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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 al17


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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 chemical18


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Outcomes

1.Cooperation and communications withcreators and user's of the material

2.MOU with other state agency (DPR*)

3. Collaboration with Federal agencies,Universities, research agencies

4. Other participations

5. Nano toolkit

*DPR- Department of Pesticide Regulations( Cal EPA) 20


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