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NANOSH Hunting for Nanoparticles. A Year in the Life of an Aerosol Scientist I.L. Tuinman. Layout. Project NANOSH: Nanoparticle Occupational Safety and Health Measurements on site: can we find and characterize a nanoparticle health hazards in workplace environments?
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NANOSH Hunting for Nanoparticles A Year in the Life of an Aerosol Scientist I.L. Tuinman
I.L. Tuinman Layout • 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
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 9000for active surface area I.L. Tuinman NANOSH Occupational Hygiene: on site measurements TEM photograph of fumed silica collected with a personal sampler
I.L. Tuinman NANOSH 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
I.L. Tuinman NANOSH Typical Result ELPI emptying bags with dust particles into a filling system
I.L. Tuinman I.L. Tuinman NANOSH Typical Result CPC emptying bags with dust particles into a filling system
I.L. Tuinman NANOSH 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 nanoparticle Region as shown in the graphs below
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 I.L. Tuinman NANOSH Filtration test set-up • Three contributing test houses, HSL, TNO, and CIOP, tested six selected filters with NaCl and one other test aerosol Parameters tested
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 I.L. Tuinman NANOSH Types of filter materials to be included
I.L. Tuinman NANOSH Controlled flow through filter Dry, clean air 36 or 3.6 l/min Filter test chamber Aerosolmixer To r Excess aerosol flow SMPS with DMA 3085 and UCPC 3786 Diffusion dryer Collison nebulizer
I.L. Tuinman NANOSH Results Electret A
I.L. Tuinman NANOSH Results Electret B
I.L. Tuinman NANOSH Results low-efficiency electret filter
I.L. Tuinman NANOSH Results non-electret filter
I.L. Tuinman NANOSH Conclusions and Remarks • It is very difficult to measure an increase in nanoparticles in workplaces due to the height of and fluctuations in the backgroundExperiments 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. Tuinman NANOSH Thank you for your attention! Point of Contact for TNO Respiratory Protection and Clothing Frans van Gemerden Email: frans.vangemerden@tno.nl Tel: +31 6 52803608