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الخلد في اليه نازعتنينفسي

Toxicological aspects of Toxicological aspects of human exposure to human exposure to

nanoparticlesnanoparticlesEssay ByEssay By

Nashwa Mostafa MahmoudNashwa Mostafa Mahmoud

Demonstrator in forensic medicine & Demonstrator in forensic medicine & clinical toxicology departmentclinical toxicology department

Faculty of Medicine, Sohag Faculty of Medicine, Sohag UniversityUniversity

What is NanoWhat is Nano? ?

Nanometer =10Nanometer =10-9-9

((3-43-4 atoms side by atoms side by sideside))

cm mm m nm

10-2 10-3 10-610-4 10-5 10-7 10-8 10-9(m)

Hair100 m

Penny2 cm

Raindrop1 mm

Red Blood Cell5 m

What Is A Nanometer?

80100 60 40 20

(nm)

Gold Particles13 nm & 50 nm

Flu Virus100 nm

1

Bacteriophage60-70 nm

DNADiameter = 2 nm

Now Entering The NANO-ZONE

What is a What is a nanoparticlenanoparticle??

Nanoparticles: are particles Nanoparticles: are particles or materials with one or or materials with one or more dimensions at the more dimensions at the nanoscale nanoscale (< 100 nm). .

Nanoparticles / Nanoparticles / Nanomaterials are Nanomaterials are the the building blocksbuilding blocks for for nanotechnologynanotechnology

fullerenes

QDs

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

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

Nanotechnology Is Not A New Phenomenon

stained-glass windows of stained-glass windows of the great medieval the great medieval cathedrals also contain cathedrals also contain metallic NPsmetallic NPs

Size & Shape Determine Size & Shape Determine ColourColour

Gold NP in glass25 nm RED

50 nm GREEN100 nm ORANGE

ClassificationsClassifications::

• in volcanoesin volcanoes• forest fires, forest fires, • dust storms ,dust storms ,• soot, soot, • bacteria ,virus, bacteria ,virus,

dust, dust, • ocean wavesocean waves

According to According to sources:sources:Natural Natural

NPsNPs:: volcanoesvolcanoes

bacteriabacteria

virusvirus

ocean ocean waveswaves

dust dust stormsstorms

AnthropogenicAnthropogenic NPsNPs

• Diesel and engine Diesel and engine exhaust exhaust

• Welding fumes, mining• combustion by-products,

(coal/oil/gas boilers)• Indoor pollution: cooking,

cigarette, candle smoke, Frying meat, textile fibers, skin particles, spores, dust mites.

•Incidental NPsIncidental NPs

in nanotechnology: carbon black, •fumed silica,• titanium dioxide (TiO2)•iron oxide,• quantum dots (QDs), •fullerenes, •carbon nanotubes (CNTs),

•Engineered NPs:

fullerenes

CNTs

dendrimer

QDs

According to According to DimensionalityDimensionality::

1D nanomaterials1D nanomaterials (NM) ( noanoplate)(NM) ( noanoplate)

monolayer films monolayer films

(one atom deep) (one atom deep) 2D NM2D NM :( Nanorod) :( Nanorod)

Carbon nanotubesCarbon nanotubes 3D NM 3D NM ::

(nanoparticle)(nanoparticle)

Dendrimers, Quantum Dendrimers, Quantum dots dots

Fullerenes (carbon 60)Fullerenes (carbon 60)FullereneFullereness

Carbon Carbon nanotubesnanotubes

According to According to NP compositionNP composition inorganic inorganic ::metalsmetals (iron,titanium, (iron,titanium, gold, silver) gold, silver) metal oxidesmetal oxides (titanium oxide, zinc oxide, silica (titanium oxide, zinc oxide, silica and iron oxide etc.)and iron oxide etc.)

organicorganic (fullerenes, CNT, (fullerenes, CNT, nanopolymers)nanopolymers)..

NPs:NPs: a a single single constituent material constituent material or be a or be a composite composite nanomaterialsnanomaterials..

Nanoparticle is Nanoparticle is everywhereeverywhere::

• 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

Nanotechnology Products Are Nanotechnology Products Are Here 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 withNano Silver

Unique Properties of Nanoscale Unique Properties of Nanoscale MaterialsMaterials

Vastly increased surface area per unit massVastly increased surface area per unit mass

IronIron100100 g Irong Iron::

diameter = 3.0 diameter = 3.0 cmcmSurface area = Surface area = 26 cm226 cm2

100 g Iron:diameter = 50 nmSurface area = 1,500 m2

Why Is Nanotechnology So Cool?

Bulk Gold

mp = 1064° C Color = gold

1 nm gold particles

mp = 700 °C max = 420 nm

Color = brown-yellow

20 nm gold particles

mp = ~1000 °C max = 521 nm

Color = red

100 nm gold particles

mp = ~1000 °C max = 575 nm

Color = purple-pink

Quantum size effects : Quantum size effects : different mechanical, different mechanical, electronic, photonic, optical, electronic, photonic, optical, magnetic propertiesmagnetic properties

Toxicology of Nanoparticles: A Matter of Size?

RiskRisk=function( =function( ExposureExposure x x toxicitytoxicity ) )

Potential Human Exposure Routes and Potential Human Exposure Routes and PathwaysPathways::•Inhalation: The principal route of human exposure.•Dermal •Gastrointestinal •Other routes: injection, tissue prothesisCellular interaction with NPs:

•Cellular uptake: all types of cells: •Mechanisms of toxicity: inflammation, oxidative stress response, disturbed cell function ,allergy

Factors affecting NP Toxicity:

DoseDose:: Dose independent toxicityDose independent toxicity Size & Surface area:Size & Surface area:

Reduction to the nanoscale Reduction to the nanoscale increase of surface to volume increase of surface to volume ratio enhancing the intrinsic ratio 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

• Shape, crystal typeToxicity of TiO2 anatase

>> TiO2 rutile

• Chemistry

Lung inflammation:(UFP, CNTs, quartz) >

TiO2 >MgO In vitro cytotoxicity:Fe2O3 = asbestos >

ZnO > TiO2 = ZrO2

Health Hazards of NPsHealth Hazards of NPs:: Inhalation Exposure Studies with Inhalation Exposure Studies with

NMNM•NPsNPs can enter lung tissues can enter lung tissues and be distributed to other and be distributed to other organs and tissuesorgans and tissues•NPsNPs not captured by not captured by respiratory defense systemsrespiratory defense systems•Observed effectsObserved effects: impaired : impaired macrophage clearance, macrophage clearance, inflammation, epithelial cell inflammation, epithelial cell proliferation, fibrosis, proliferation, fibrosis, emphysema, appearance of emphysema, appearance of tumorstumors

GIT uptake of NPsGIT uptake of NPs::

NPs found in colon tissue NPs found in colon tissue of patients with cancer, of patients with cancer, CrohnCrohn’’s , ulcerative s , ulcerative colitis colitis

Dermal uptake of Dermal uptake of NPs: NPs:

Reports of penetration of Reports of penetration of intact skin in test system intact skin in test system models by: models by: – Multi-walled carbon nanotubesMulti-walled carbon nanotubes– Substituted fullerenesSubstituted fullerenes– Quantum dotsQuantum dots

Titanium dioxide NPs,Titanium dioxide NPs, used used as a sunscreen were observed as a sunscreen were observed to catalyze DNA damage both to catalyze DNA damage both in vitro in vitro and and in vivoin vivo

•Nervous Nervous systemsystem uptake of uptake of NPs:NPs: YesYes or or nono Neuronal uptake of inhaled NPs :via Neuronal uptake of inhaled NPs :via

olfactory nervesolfactory nerves or/and BBB or/and BBB Experimental evidence : Experimental evidence : neurodegenerative diseases, such as neurodegenerative diseases, such as

AlzheimerAlzheimer’’s disease, Parkinsons disease, Parkinson’’s s disease, Pickdisease, Pick’’s disease, are associated s disease, are associated with oxidative stress and accumulation with oxidative stress and accumulation of metals (like copper, aluminum, zinc, of metals (like copper, aluminum, zinc, but especially iron) in brain regions but especially iron) in brain regions associated with function loss and cell associated with function loss and cell damage damage

Positive effects of NPsPositive effects of NPs::

AntioxidantsAntioxidants: Fullerene : Fullerene Derivatives have Derivatives have neuroprotective properties and neuroprotective properties and antiapoptotic activityantiapoptotic activity ..

Anti-microbial activityAnti-microbial activity: : antimicrobial effect, such as antimicrobial effect, such as silver, titanium dioxide, silver, titanium dioxide, fullerenes, zinc oxide, and fullerenes, zinc oxide, and magnesium oxide magnesium oxide

Strategies to control exposure to Strategies to control exposure to NPsNPs::

Useful measures at work :Useful measures at work :

•• Total enclosure of the process Total enclosure of the process

•• Limitation of numbers of workersLimitation of numbers of workers

•• Partial enclosure with local exhaust ventilation Partial enclosure with local exhaust ventilation

•• Local exhaust ventilation Local exhaust ventilation

•• General ventilation General ventilation •• Reduction in periods of exposure Reduction in periods of exposure

•• Regular cleaning of wall and other surfaces Regular cleaning of wall and other surfaces •• Use of suitable Use of suitable personal protective equipmentpersonal protective equipment

•• Prohibition of eating and drinkingProhibition of eating and drinking

Number Metric methods:Optical Particle CounterCondensation particle counterScanning 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:

Condensation particle counter

ConclusionConclusion::

Nanotechnolog is a nanocoin Nanotechnolog is a nanocoin