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Comparison of nanoparticle exposures between fumed and sol-gel nano-silica manufacturing facilities.

Oh S, Kim B, Kim H - Ind Health (2014)

Bottom Line: Due to the high-temperature formation process, the particles exhibited a sintering coagulation.In the SS packing process that includes a manual jet mill operation, the GM NC was calculated to be 72,000 particles/cm(3) with an assumption of 1,000,000 particles/cm(3) when the upper limit is exceeded (5% of total measure).The particles from SS process had a spherical-shaped morphology with GMD measured by SMPS of 94 nm.

View Article: PubMed Central - PubMed

Affiliation: Ministry of Employment and Labor, Republic of Korea.

ABSTRACT
Silica nanoparticles (SNPs) are widely used all around the world and it is necessary to evaluate appropriate risk management measures. An initial step in this process is to assess worker exposures in their current situation. The objective of this study was to compare concentrations and morphologic characteristics of fumed (FS) and sol-gel silica nanoparticles (SS) in two manufacturing facilities. The number concentration (NC) and particle size were measured by a real-time instrument. Airborne nanoparticles were subsequently analyzed using a TEM/EDS. SNPs were discharged into the air only during the packing process, which was the last manufacturing step in both the manufacturing facilities studied. In the FS packing process, the geometric mean (GM) NC in the personal samples was 57,000 particles/cm(3). The geometric mean diameter (GMD) measured by the SMPS was 64 nm. Due to the high-temperature formation process, the particles exhibited a sintering coagulation. In the SS packing process that includes a manual jet mill operation, the GM NC was calculated to be 72,000 particles/cm(3) with an assumption of 1,000,000 particles/cm(3) when the upper limit is exceeded (5% of total measure). The particles from SS process had a spherical-shaped morphology with GMD measured by SMPS of 94 nm.

No MeSH data available.


Related in: MedlinePlus

Characteristics of silica nanoparticles in the packing process according to timepassage: fumed silica factory, (a) particle number concentration, (b) particle sizedistribution with particle number concentration; sol-gel silica factory, (c)particle number concentration, (d) particle size distribution with particle numberconcentration, (e) comparison of particle distribution in two silica nanoparticlefactories; dn/dlogDp, normalized concentration.
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fig_003: Characteristics of silica nanoparticles in the packing process according to timepassage: fumed silica factory, (a) particle number concentration, (b) particle sizedistribution with particle number concentration; sol-gel silica factory, (c)particle number concentration, (d) particle size distribution with particle numberconcentration, (e) comparison of particle distribution in two silica nanoparticlefactories; dn/dlogDp, normalized concentration.

Mentions: FS: fumed silica nanoparticle, SS: sol-gel silica nanoparticle. † Inworking. ‡ Geometric mean diameter from the scanning mobility particlesizer (SMPS). Bulk powder: physical diameter of primary particle obtained from TEManalysis. Agglomerate: physical diameter of airborne agglomerate obtained from TEManalysis.


Comparison of nanoparticle exposures between fumed and sol-gel nano-silica manufacturing facilities.

Oh S, Kim B, Kim H - Ind Health (2014)

Characteristics of silica nanoparticles in the packing process according to timepassage: fumed silica factory, (a) particle number concentration, (b) particle sizedistribution with particle number concentration; sol-gel silica factory, (c)particle number concentration, (d) particle size distribution with particle numberconcentration, (e) comparison of particle distribution in two silica nanoparticlefactories; dn/dlogDp, normalized concentration.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4209587&req=5

fig_003: Characteristics of silica nanoparticles in the packing process according to timepassage: fumed silica factory, (a) particle number concentration, (b) particle sizedistribution with particle number concentration; sol-gel silica factory, (c)particle number concentration, (d) particle size distribution with particle numberconcentration, (e) comparison of particle distribution in two silica nanoparticlefactories; dn/dlogDp, normalized concentration.
Mentions: FS: fumed silica nanoparticle, SS: sol-gel silica nanoparticle. † Inworking. ‡ Geometric mean diameter from the scanning mobility particlesizer (SMPS). Bulk powder: physical diameter of primary particle obtained from TEManalysis. Agglomerate: physical diameter of airborne agglomerate obtained from TEManalysis.

Bottom Line: Due to the high-temperature formation process, the particles exhibited a sintering coagulation.In the SS packing process that includes a manual jet mill operation, the GM NC was calculated to be 72,000 particles/cm(3) with an assumption of 1,000,000 particles/cm(3) when the upper limit is exceeded (5% of total measure).The particles from SS process had a spherical-shaped morphology with GMD measured by SMPS of 94 nm.

View Article: PubMed Central - PubMed

Affiliation: Ministry of Employment and Labor, Republic of Korea.

ABSTRACT
Silica nanoparticles (SNPs) are widely used all around the world and it is necessary to evaluate appropriate risk management measures. An initial step in this process is to assess worker exposures in their current situation. The objective of this study was to compare concentrations and morphologic characteristics of fumed (FS) and sol-gel silica nanoparticles (SS) in two manufacturing facilities. The number concentration (NC) and particle size were measured by a real-time instrument. Airborne nanoparticles were subsequently analyzed using a TEM/EDS. SNPs were discharged into the air only during the packing process, which was the last manufacturing step in both the manufacturing facilities studied. In the FS packing process, the geometric mean (GM) NC in the personal samples was 57,000 particles/cm(3). The geometric mean diameter (GMD) measured by the SMPS was 64 nm. Due to the high-temperature formation process, the particles exhibited a sintering coagulation. In the SS packing process that includes a manual jet mill operation, the GM NC was calculated to be 72,000 particles/cm(3) with an assumption of 1,000,000 particles/cm(3) when the upper limit is exceeded (5% of total measure). The particles from SS process had a spherical-shaped morphology with GMD measured by SMPS of 94 nm.

No MeSH data available.


Related in: MedlinePlus