Bao cao nano silver ppt

Environmental Health and Safety Concerns of Nano Silver • Potential to be released into environment • May be toxic to beneficial microbes • Impact on aquatic species 6... Nano Material

Nano Silver

Neena Sahasrabudhe

DTSC

1

Nano Material Applications

• CONSUMER PRODUCTS

• PESTICIDES AND ANTIMICROBIALS

• MEDICAL DIAGNOSTICS AND

PHARMACEUTICALS

• BIOTECHNOLOGY

• AUTOMOTIVE

• PAINTS AND COATINGS

• COSMETICS AND PERSONAL CARE

• ENERGY AND ELECTRONICS

Nano silver uses

• Medical Products—wound dressings,

surgical gauze, bandages

• Textiles and Clothing

• Sporting Goods

• Aerospace and Electronics

3

Why are nano materials popular?

• Different Physical and Chemical

Nano materials also used in

• Environmental Remediation

• Decontamination of Pollutants

5

Environmental Health and Safety

Concerns of Nano Silver

• Potential to be released into environment

• May be toxic to beneficial microbes

• Impact on aquatic species

6

Nano Material Lifecycle

Manufacture Transportation Storage

Consumers / Public

Materials

Workers Waste

Soil/

Sediment Water

Plant Animal

Food

Environment

Integration

Consumer Products

Devices Processes

Facility

Systems

Release Disposal

7

‘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

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 9

Other Concerns

• Other consumer products lined with antibacterial nano silver

• Food containers, baby bottles

• Band aids

• Medicinal supplements

• FDA nanotechnology section

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 do 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

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

Outcomes

1.Cooperation and communications with

creators 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

Thank you

Neena Sahasrabudhe, Ph.D

916/324 8660