3. Toxicological aspects of humanToxicological aspects of human
exposure to nanoparticlesexposure to nanoparticles
Essay ByEssay By
Nashwa Mostafa MahmoudNashwa Mostafa Mahmoud
Demonstrator in forensic medicine &Demonstrator in forensic medicine &
clinical toxicology departmentclinical toxicology department
Faculty of Medicine, Sohag UniversityFaculty of Medicine, Sohag University
4. What is NanoWhat is Nano??
Nanometer =10Nanometer =10-9-9
))3-43-4atoms side by sideatoms side by side((
5. cm mm µm nm
10-2
10-3
10-6
10-4
10-5
10-7
10-8
10-9(m)
Hair
100 µm
Penny
2 cm
Raindrop
1 mm
Red Blood Cell
5 µm
What Is A Nanometer?
6. 80100 60 40 20
(nm)
Gold Particles
13 nm & 50 nm
Flu Virus
100 nm
1
Bacteriophage
60-70 nm
DNA
Diameter = 2 nm
Now Entering The NANO-ZONE
7. What is a nanoparticleWhat is a nanoparticle??
Nanoparticles: are particles orNanoparticles: are particles or
materials with one or morematerials with one or more
dimensions at the nanoscaledimensions at the nanoscale
(< 100 nm)..
Nanoparticles / NanomaterialsNanoparticles / Nanomaterials
areare the building blocksthe building blocks forfor
nanotechnologynanotechnology
fullerenes
QDs
8. Nanotechnology & Nanoscience
It is design, characterization, production and
application of structures by controlling
shape and size at the nanoscale
(< 100 nm) such as molecules and atomssuch as molecules and atoms
9. Nanotechnology Is Not A New
Phenomenon
The KING Cup:
4th
Century A.D.
(The British Museum.)
Image of
silver/gold
nanoparticle
(50 nm)
Green = Reflected Light
Red = Transmitted Light
10. Nanotechnology Is
Not A New
Phenomenon
stained-glass windows of thestained-glass windows of the
great medieval cathedralsgreat medieval cathedrals
also contain metallic NPsalso contain metallic NPs
11. Size & Shape DetermineSize & Shape Determine
ColourColour
Gold NP in glass
25nm RED
50nm GREEN
100nm ORANGE
15. According to DimensionalityAccording to Dimensionality::
1D nanomaterials1D nanomaterials
(NM) ( noanoplate)(NM) ( noanoplate)
monolayer filmsmonolayer films
(one atom deep)(one atom deep)
2D NM2D NM :( Nanorod):( Nanorod)
Carbon nanotubesCarbon nanotubes
3D NM3D NM :(nanoparticle):(nanoparticle)
Dendrimers, Quantum dotsDendrimers, Quantum dots
Fullerenes (carbon 60)Fullerenes (carbon 60)
FullereneFullerene
ss
Carbon nanotubesCarbon nanotubes
16. According toAccording to NP compositionNP composition
inorganicinorganic ::metalsmetals (iron,titanium, gold,(iron,titanium, gold,
silver)silver) metal oxidesmetal oxides (titanium oxide,(titanium oxide,
zinc oxide, silica and iron oxide etczinc oxide, silica and iron oxide etc.).)
organicorganic (fullerenes, CNT,(fullerenes, CNT,
nanopolymersnanopolymers).).
NPs:NPs: aa singlesingle constituent material orconstituent material or
be abe a compositecomposite nanomaterialsnanomaterials..
17. Nanoparticle is everywhereNanoparticle is everywhere::
• Information & communication:Information & communication:
• power engineeringpower engineering
• Industrial engineeringIndustrial engineering
• Chemical industryChemical industry
• Medicine & imagingMedicine & imaging
• Environmental engineeringEnvironmental engineering
• Food and DrinkFood and Drink
• HouseholdHousehold
• SportsSports
18. Nanotechnology Products Are HereNanotechnology Products Are Here
NowNow
Dermatone
SPF 20
Natural
Formula
Kodak Inkjet
Photo Papers
Nanotec Nanoseal®
Wood
Eddie Bauer
Ruston Fit
Nano-Tex
Khakis
Hummer
H2
Toshiba’s Lithium-
Ion Battery
Kohler CleanCoat
Technology
Nanosolar’s
Utility Panel™
Socks with
Nano Silver
19. Unique Properties of NanoscaleUnique Properties of Nanoscale
MaterialsMaterials
Vastly increased surface area per unit massVastly increased surface area per unit mass
IronIron
100100g Irong Iron::
diameter = 3.0 cmdiameter = 3.0 cm
Surface area = 26Surface area = 26
cm2cm2
100g Iron:
diameter = 50 nm
Surface area =
1,500 m2
20. Why Is Nanotechnology So Cool?
Bulk Gold
mp = 1064° C
Color = gold
1 nm gold particles
mp = 700 °C
λmax = 420 nm
Color = brown-yellow
20 nm gold particles
mp = ~1000 °C
λmax = 521 nm
Color = red
100 nm gold
particles
mp = ~1000 °C
λmax = 575 nm
Color = purple-pink
Quantum size effects : differentQuantum size effects : different
mechanical, electronic, photonic,mechanical, electronic, photonic,
optical, magnetic propertiesoptical, magnetic properties
21. Toxicology of Nanoparticles:
A Matter of Size?
RiskRisk=function(=function( ExposureExposure xx toxicitytoxicity ))
Potential Human Exposure Routes and PathwaysPotential Human Exposure Routes and Pathways::
•Inhalation: The principal route of human exposure.
•Dermal
•Gastrointestinal
•Other routes: injection, tissue prothesis
Cellular interaction with NPs:
•Cellular uptake: all types of cells:
•Mechanisms of toxicity: inflammation,
oxidative stress response, disturbed cell
function ,allergy
22. Factors affecting NP Toxicity:
DoseDose::
Dose independent toxicityDose independent toxicity
Size & Surface area:Size & Surface area:
Reduction to the nanoscaleReduction to the nanoscale
increase of surface to volumeincrease of surface to volume
ratio enhancing the intrinsicratio enhancing the intrinsic
toxicitytoxicity
Lung inflammation studies
– TiO2: 21 nm v. 300 nm
inhaled by rats
– TiO2: 20 nm v. 250 nm
instilled in rats and mice
24. Health Hazards of NPsHealth Hazards of NPs::
Inhalation Exposure Studies with NMInhalation Exposure Studies with NM
•NPsNPs can enter lung tissues and becan enter lung tissues and be
distributed to other organs anddistributed to other organs and
tissuestissues
•NPsNPs not captured by respiratorynot captured by respiratory
defense systemsdefense systems
•Observed effectsObserved effects: impaired: impaired
macrophage clearance,macrophage clearance,
inflammation, epithelial cellinflammation, epithelial cell
proliferation, fibrosis, emphysema,proliferation, fibrosis, emphysema,
appearance of tumorsappearance of tumors
25. GIT uptake of NPsGIT uptake of NPs::
NPs found in colon tissue ofNPs found in colon tissue of
patients with cancer,patients with cancer,
CrohnCrohn’’s , ulcerative colitiss , ulcerative colitis
26. Dermal uptake of NPs:Dermal uptake of NPs:
Reports of penetration of intactReports of penetration of intact
skin in test system models by:skin in test system models by:
– Multi-walled carbon nanotubesMulti-walled carbon nanotubes
– Substituted fullerenesSubstituted fullerenes
– Quantum dotsQuantum dots
Titanium dioxide NPs,Titanium dioxide NPs, usedused
as a sunscreen were observedas a sunscreen were observed
to catalyze DNA damage bothto catalyze DNA damage both
in vitroin vitro andand in vivoin vivo
27. •NervousNervous systemsystem uptake of NPs:uptake of NPs:
YesYes oror nono
Neuronal uptake of inhaled NPs :viaNeuronal uptake of inhaled NPs :via
olfactory nervesolfactory nerves or/and BBBor/and BBB
Experimental evidence :Experimental evidence :
neurodegenerative diseases, such asneurodegenerative diseases, such as
AlzheimerAlzheimer’’s disease, Parkinsons disease, Parkinson’’s disease,s disease,
PickPick’’s disease, are associated with oxidatives disease, are associated with oxidative
stress and accumulation of metals (likestress and accumulation of metals (like
copper, aluminum, zinc, but especially iron)copper, aluminum, zinc, but especially iron)
in brain regions associated with functionin brain regions associated with function
loss and cell damageloss and cell damage
28. Positive effects of NPsPositive effects of NPs::
AntioxidantsAntioxidants: Fullerene Derivatives: Fullerene Derivatives
have neuroprotective propertieshave neuroprotective properties
and antiapoptotic activityand antiapoptotic activity ..
Anti-microbial activityAnti-microbial activity::
antimicrobial effect, such as silver,antimicrobial effect, such as silver,
titanium dioxide, fullerenes, zinctitanium dioxide, fullerenes, zinc
oxide, and magnesium oxideoxide, and magnesium oxide
29. Strategies to control exposure to NPsStrategies to control exposure to NPs::
Useful measures at work :Useful measures at work :
•• Total enclosure of the processTotal enclosure of the process
•• Limitation of numbers of workersLimitation of numbers of workers
•• Partial enclosure with local exhaust ventilationPartial enclosure with local exhaust ventilation
•• Local exhaust ventilationLocal exhaust ventilation
•• General ventilationGeneral ventilation
•• Reduction in periods of exposureReduction in periods of exposure
•• Regular cleaning of wall and other surfacesRegular cleaning of wall and other surfaces
•• Use of suitable personalUse of suitable personal
protective equipmentprotective equipment
•• Prohibition of eating and drinkingProhibition of eating and drinking
30. Number Metric methods:
Optical Particle Counter
Condensation particle counter
Scanning mobility particle sizer (SMPS(
Electrical low pressure impactor (ELPI(
Surface area Metric methods:
Epiphaniometer
BET bulk analysis
Image analysis Metric methods:
scanning (SEM) or transmission electro-microscopes
(TEM): Analysis of morphology. Samples may be
collected by personal samplers or size selective static
samplers.
Detection and Measurements of
NPs:
Condensati
on particle
counter
Let’s think about some possibilities. . .
How many of you have been through a metal detector at the airport?
That’s a type of sensor.
And we all know what a smoke detector is – we have them here in our classroom and at home.
That’s another type of sensor.
But what if we could build a sensor that could sense at the nanoscale?
If the smoke detector was that sensitive it would go off whenever someone outside the school lit a match
And what if the sensor itself was nano-sized?
Over 800 consumer products listed on in the Woordrow Wilson Institute’s Consumer Products Inventory of Nanotechnology Products
So why is working at the nanoscale so important?
In the past, we have tried to shrink things down.
The first computer was so large it filled an entire room.
We have been able to shrink things down so that now we have laptop computers and hand-held computer games.
But scientists have realized for many years that we can only go so far.
The world of nanotechnology allows us to build things molecule by molecule
From the bottom up!
This opens up a world of possibilities.
