nanosh hunting for nanoparticles a year in the life of an aerosol scientist i.l. tuinman
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NANOSH Hunting for Nanoparticles
A Year in the Life of an Aerosol Scientist
I.L. Tuinman
I.L. Tuinman
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Project NANOSH: Nanoparticle Occupational Safety and Health
Measurements on site: can we find and characterize a nanoparticle
health hazards in workplace environments?
Filtration: how well are nanoparticles filtered by respiratory protection
filters
I.L. Tuinman
NANOSH Nanoparticle Occupational Safety and Health
Oberdorster and other authors published data showing nanoparticles
can be more toxic than micron-sized particles
Some nanoparticles can even cross the brain barrier
Unintentional production of man-made nanoparticles was already high
but increasingly nanoparticles are produced intentionally because of
their improved properties and miniaturization of instruments
Maybe standard Personal Protective equipment does not provide
proper protection
I.L. Tuinman
Content NANOSH-project
Characterization of nanoparticles (WP1)
Perform measurements to determine Workplace Exposure (WP2)
Design a proper protocol for such measurements
Interpret the data
Test respiratory filters or respirators against nanoparticles
Test toxicology of nanoparticles (not discussed here) in 3 WP:
genotoxicity, pulmonary inflammation and the effect of particles on
microcirculation
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Occupational Hygiene: on site measurements
Total measurement equipment >100 kg, k€500 was transported in a
small van from site to site
ELPI
SMPS
Condensation Particle Counters (Portacounts)
Personal sampler
NSAM/ LQ1/Aerotrak 9000
for active surface area
TEM photograph of fumed silica collected with a personal sampler
I.L. TuinmanNANOSH
Electrical Low Pressure Impactor, ELPI
+ Large size range (30 nm-10 µm)
+ Fast: high time resolution
combined with some size
resolution (12 size classes)
+ Large concentration range
+ Sample analysis afterwards
possible
Measurement of exposure to ultrafine/nanoparticles
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Typical Result ELPI emptying bags with dust particles into a filling system
I.L. TuinmanI.L. TuinmanNANOSH
Typical Result CPC emptying bags with dust particles into a filling system
I.L. TuinmanNANOSH
Why filter tests with Nanoparticles?
Authors like Balazy et al. Ann. Occup. Hyg. 50(3), 2006 found filters with the most penentrating particle size in the nanoparticleRegion as shown in the graphs below
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Parameters tested
Filter Materials
Test Aerosols: NaCl and Carbon black
Air Flow(s): 1 cm/s and 10 cm/s (corresponds to 95 l/min in facelets)
Test set-up: adapted EN143 set-up with SMPS (TSI 3080) for
measurement
Filtration test set-up
• Three contributing test houses, HSL, TNO, and CIOP, tested six selected filters with NaCl and one other test aerosol
I.L. TuinmanNANOSH
Types of filter materials to be included
A defined selection of electrostatic and mechanical air filter materials in
sheet form should be obtained covering the basic filter types applied in
RPE and ventilation systems:
Electrostatically spun polycarbonate fibers
Electrostatically charged split fibers
Meltblown
Nanofibers
Glass fiber filter
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Collisonnebulizer
Diffusion dryer
Aerosol mixer
Dry, clean air
To rExcess aerosol flow
Filter test chamber
36 or 3.6 l/min
SMPS with DMA 3085 and UCPC 3786
Controlled flow through filter
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Results Electret A
10 100 10001
10
P NaCl 1 cm/s
P NaCl 10 cm/s
P CB 1 cm/s
P CB 10 cm/s
Particle diameter (nm)
Pe
ne
tra
tio
n (
%)
I.L. TuinmanNANOSH
Results Electret B
10 100 10001
10
NaCl 1 cm/s
NaCl 10 cm/s
CB 1 cm/s
CB 10 cm/s
Dp (nm)
Pe
ne
tra
tio
n (
%)
I.L. TuinmanNANOSH
Results low-efficiency electret filter
10 100 10001
10
100
NaCl 1 cm/s
NaCl 10 cm/s
CB 1 cm/s
CB 10 cm/s
Dp (nm)
Pe
ne
tra
tio
n (
%)
I.L. TuinmanNANOSH
Results non-electret filter
10 100 10000.01
0.1
P NaCl 1 cm/s
P NaCl 10 cm/s
P CB 1 cm/s
P CB 10 cm/s
Dp (nm)
Pe
ne
tra
tio
n (
%)
I.L. TuinmanNANOSH
Conclusions and Remarks
It is very difficult to measure an increase in nanoparticles in
workplaces due to the height of and fluctuations in the background
Experiments in clean rooms can add valuable information.
Personal samplers can show significant exposure to manufactured
nanoparticles
High efficiency electret filters tend to have their most penetrating
particle size in the nanoparticle range. This has to be taken into
account when selecting and testing respirators for workplaces where
nanoparticles are expected.
I.L. TuinmanNANOSH
Thank you for your attention!
Point of Contact for TNO Respiratory Protection and Clothing
Frans van Gemerden
Email: [email protected]: +31 6 52803608