title: Occupational Exposure to Multi-Walled Carbon Nanotubes During Commercial Production Synthesis and Handling.
abstract: The world-wide production of carbon nanotubes (CNTs) has increased substantially in the last decade, leading to occupational exposures. There is a paucity of exposure data of workers involved in the commercial production of CNTs. The goals of this study were to assess personal exposure to multi-walled carbon nanotubes (MWCNTs) during the synthesis and handling of MWCNTs in a commercial production facility and to link these exposure levels to specific activities. Personal full-shift filter-based samples were collected, during commercial production and handling of MWCNTs, R&D activities, and office work. The concentrations of MWCNT were evaluated on the basis of EC concentrations. Associations were studied between observed MWCNT exposure levels and location and activities. SEM analyses showed MWCNTs, present as agglomerates ranging between 200 nm and 100 µm. Exposure levels of MWCNTs observed in the production area during the full scale synthesis of MWCNTs (N = 23) were comparable to levels observed during further handling of MWCNTs (N = 19): (GM (95% lower confidence limit-95% upper confidence limit)) 41 μg m(-3) (20-88) versus 43 μg m(-3) (22-86), respectively. In the R&D area (N = 11) and the office (N = 5), exposure levels of MWCNTs were significantly (P < 0.05) lower: 5 μg m(-3) (2-11) and 7 μg m(-3) (2-28), respectively. Bagging, maintenance of the reactor, and powder conditioning were associated with higher exposure levels in the production area, whereas increased exposure levels in the R&D area were related to handling of MWCNTs powder.
authors.affiliation: 1.TNO - PO Box 360, Zeist, The Netherlands; eelco.kuijpers@tno.nl.
authors.forename: Eelco
authors.initials: E
authors.lastname: Kuijpers
authors.affiliation: 1.TNO - PO Box 360, Zeist, The Netherlands; 2.IRAS - Institute for Risk Assessment Sciences, Molecular Epidemiology and Risk Assessment Utrecht, Yalelaan 1, 3584 CL, Utrecht, The Netherlands;
authors.forename: Cindy
authors.initials: C
authors.lastname: Bekker
authors.affiliation: 1.TNO - PO Box 360, Zeist, The Netherlands;
authors.forename: Wouter
authors.initials: W
authors.lastname: Fransman
authors.affiliation: 1.TNO - PO Box 360, Zeist, The Netherlands;
authors.forename: Derk
authors.initials: D
authors.lastname: Brouwer
authors.affiliation: 1.TNO - PO Box 360, Zeist, The Netherlands;
authors.forename: Peter
authors.initials: P
authors.lastname: Tromp
authors.affiliation: 2.IRAS - Institute for Risk Assessment Sciences, Molecular Epidemiology and Risk Assessment Utrecht, Yalelaan 1, 3584 CL, Utrecht, The Netherlands;
authors.forename: Jelle
authors.initials: J
authors.lastname: Vlaanderen
authors.affiliation: 3.Katholieke Universiteit Leuven - Centre for Environment and Health, Kapucijnenvoer 35/5, 3000, Leuven, Belgium; 4.IDEWE, External Service for Prevention and Protection at Work, Interleuvenlaan 58, 3001, Heverlee, Belgium;
authors.forename: Lode
authors.initials: L
authors.lastname: Godderis
authors.affiliation: 3.Katholieke Universiteit Leuven - Centre for Environment and Health, Kapucijnenvoer 35/5, 3000, Leuven, Belgium;
authors.forename: Peter
authors.initials: P
authors.lastname: Hoet
authors.affiliation: 5.Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, 6120 Executive Boulevard, Bethesda, MD, USA.
authors.forename: Qing
authors.initials: Q
authors.lastname: Lan
authors.affiliation: 5.Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, 6120 Executive Boulevard, Bethesda, MD, USA.
authors.forename: Debra
authors.initials: D
authors.lastname: Silverman
authors.affiliation: 2.IRAS - Institute for Risk Assessment Sciences, Molecular Epidemiology and Risk Assessment Utrecht, Yalelaan 1, 3584 CL, Utrecht, The Netherlands;
authors.forename: Roel
authors.initials: R
authors.lastname: Vermeulen
authors.affiliation: 1.TNO - PO Box 360, Zeist, The Netherlands;
authors.forename: Anjoeka
authors.initials: A
authors.lastname: Pronk
mesh_terms: D000395:Air Pollutants, Occupational / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods*; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis; D008168:Lung / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon / Q000032:analysis*; D016273:Occupational Exposure / Q000032:analysis*; D010316:Particle Size
chemical_list: D000395:Air Pollutants, Occupational; D037742:Nanotubes, Carbon
keywords: Commercial production; multi-walled carbon nanotubes; occupational exposure.