title: Three-Day Continuous Exposure Monitoring of CNT Manufacturing Workplaces.
abstract: Continuous monitoring for possible exposure to carbon nanotubes was conducted over a period of 2 to 3 days at workplaces that manufacture multiwall carbon nanotubes (MWCNTs) and single wall carbon nanotubes (SWCNTs). To estimate the potential emission of carbon nanotubes (CNTs) and potential exposure of workers, personal sampling, area monitoring, and real-time monitoring using an scanning mobility particle sizer (SMPS) and dust monitor were conducted at workplaces where the workers manufactured CNTs. The personal and area sampling of the total suspended particulate (TSP) at the MWCNT manufacturing facilities ranged from 0.031 to 0.254 and from N.D (not detected) to 0.253 mg/m(3), respectively. This 2- to 3-day monitoring study found that nanoparticles were released when opening the chemical vapor deposit (CVD) reactor door after the synthesis of MWCNTs, when transferring the MWCNTs to containers and during blending and grinding. However, distinguishing the background concentration from the work process particle emission was complicated due to sustained and even increased particle concentrations after the work processes were terminated. The MWCNTs sampled for transmission electron microscopy (TEM) observation exhibited a tangled shape with no individual dispersed CNT structures.
authors.affiliation: Institute of Nanoproduct Safety Research, Hoseo University, Asan 336-795, Republic of Korea.
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Hanyang University, Ansan, Gyeonggi-do 426- 791, Republic of Korea.
authors.forename: Kang Ho
authors.initials: KH
authors.lastname: Ahn
authors.affiliation: Hanyang University, Ansan, Gyeonggi-do 426- 791, Republic of Korea.
authors.forename: Sun Man
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Institute of Nanoproduct Safety Research, Hoseo University, Asan 336-795, Republic of Korea.
authors.forename: Ellen
authors.initials: E
authors.lastname: Kim
authors.affiliation: Hanyang University, Ansan, Gyeonggi-do 426- 791, Republic of Korea.
authors.forename: Gun Ho
authors.initials: GH
authors.lastname: Lee
authors.affiliation: Occupational Safety & Health Research Institute, Korean Occupational Safety & Health Agency, Daejeon 305-380, Republic of Korea.
authors.forename: Jeong Hee
authors.initials: JH
authors.lastname: Han
authors.affiliation: Institute of Nanoproduct Safety Research, Hoseo University, Asan 336-795, Republic of Korea.
authors.forename: Il Je
authors.identifier: 0000-0001-5774-296X
authors.initials: IJ
authors.lastname: Yu
mesh_terms: D004784:Environmental Monitoring; D006801:Humans; D019570:Inhalation Exposure; D008168:Lung / Q000187:drug effects / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D037742:Nanotubes, Carbon / Q000009:adverse effects* / Q000737:chemistry / Q000648:ultrastructure; D016273:Occupational Exposure; D010316:Particle Size; D017132:Workplace
chemical_list: D037742:Nanotubes, Carbon