Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Nanotechnology Columns > Bergeson & Campbell, P.C. > Study Assesses Exposure in Workplaces Manufacturing Nanosized Titanium Dioxide and Silver

Lynn L. Bergeson
Managing Director
Bergeson & Campbell, P.C.

Abstract:
Inhalation Toxicology has published an article entitled, "Exposure assessment of workplaces manufacturing nanosized TiO2 and silver," which monitored the possible exposure to nanoparticles at workplaces that manufacture nano-titanium dioxide (TiO2) and nano-silver. See informahealthcare.com/doi/abs/10.3109/08958378.2011.562567 Based on the study results, the TiO2 and silver nanoparticle concentrations were relatively lower than existing occupational exposure limits.

April 23rd, 2011

Study Assesses Exposure in Workplaces Manufacturing Nanosized Titanium Dioxide and Silver

Inhalation Toxicology has published an article entitled, "Exposure assessment of workplaces manufacturing nanosized TiO2 and silver," which monitored the possible exposure to nanoparticles at workplaces that manufacture nano-titanium dioxide (TiO2) and nano-silver. See http://informahealthcare.com/doi/abs/10.3109/08958378.2011.562567 Based on the study results, the TiO2 and silver nanoparticle concentrations were relatively lower than existing occupational exposure limits.

The abstract states:

To estimate the potential exposure of workers, personal sampling, area monitoring, and real-time monitoring using a scanning mobility particle sizer (SMPS) and dust monitor were conducted at workplaces where the workers handle nanomaterials. The gravimetric concentrations of TiO2 ranged from 0.10 to 4.99 mg/m3, which were lower than the occupational exposure limit 10 mg/m3 set by the Korean Ministry of Labor or American Conference of Governmental Industrial Hygienists (ACGIH). Meanwhile, the silver metal concentrations ranged from 0.00002 to 0.00118 mg/m3, which were also lower than the silver dust 0.1 mg/m3 and silver soluble compound 0.01 mg/m3 occupational exposure limits set by the ACGIH. The particle number concentrations at the nano-TiO2 manufacturing workplaces ranged from 11,418 to 45,889 particles/cm3 with a size range of 15-710.5 nm during the reaction, although the concentration decreased to 14,000 particles/cm3 when the reaction was stopped. The particle concentrations at the TiO2 manufacturing workplaces increased during the reactor and vacuum pump operations, and during the collection of the synthesized TiO2 particles. Similarly, the particle concentrations at the silver nanoparticle manufacturing workplaces increased when the sodium citrates were weighed or reacted with the silver nitrates, and during the cleaning of the workplace. The number of silver nanoparticles in the samples obtained from the workplace manufacturing silver nanoparticles using induced coupled plasma ranged from 57,789 to 2,373,309 particles/cm3 inside the reactor with an average size of 20-30 nm and 535-25,022 particles/cm3 with a wide range of particle sizes due to agglomeration or aggregation after the release of nanoparticles into the workplace air. In contrast, the silver nanoparticles manufactured by the wet method ranged from 393 to 3526 particles/cm3 with an average size of 50 nm. Thus, when taken together, the TiO2 and silver nanoparticle concentrations were relatively lower than existing occupational exposure limits.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project