Abstract
Objectives: Black carbon (BC) originating from various combustion sources has been extensively surveyed to characterize the effects of BC on global warming and human health, and many online monitors are available. In this study, BC was considered as a surrogate for carbon-based nanomaterials in an occupational health study. Methods: Specifically, BC concentrations were monitored continuously with an aethalometer for 24h at four carbon nanotube (CNT) workplaces located in rural, urban, and industrial areas, which had different background air pollution levels. Average BC concentrations for both nonworking (background) and working periods were compared with the recommended exposure limit (REL) of 1 μg m-3 for elemental carbon that was suggested by the National Institute for Occupational Safety and Health (NIOSH). Results: Diurnal variation of BC concentrations indicated that BC measurements corresponded well with carbonaceous aerosols such as vehicle exhaust particles and CNT aerosols. In the rural CNT workplace, the average background BC concentration (0.36 μg m-3) was lower than the REL, but the BC concentration without background correction was higher than the REL during manufacturing hours. In this case, BC measurement is useful to estimate CNT exposure for comparison with the REL. Conversely, in the urban and industrial CNT workplaces, average background BC concentrations (2.05, 1.82, and 2.64 μg m-3) were well above the REL, and during working hours, BC concentrations were substantially higher than the background level at workplace C; however, BC concentrations showed no difference from the background levels at workplaces B and D. In these cases (B and D), it is hard to determine CNT exposure because of the substantial environmental exposures. Conclusion: Most of the urban ambient BC concentrations were above the REL. Therefore, further analysis and test methods for carbonaceous aerosols need to be developed so that the exposure assessment can be easily carried out at CNT workplaces with high background BC levels such as in urban and industrial areas.
Original language | English |
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Pages (from-to) | 717-730 |
Number of pages | 14 |
Journal | Annals of Occupational Hygiene |
Volume | 60 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2016 Jul 1 |
Bibliographical note
Funding Information:We acknowledge the financial support of the Ministry of Trade, Industry and Energy (MOTIE), Republic of Korea, for the National Platform Technology Project (10034758), the National Research Foundation of Korea Grant funded by the Ministry of Science, ICT and Future Planning (MSIP), Republic of Korea (2015, University-Institute cooperation program), and of the Korea Institute of Science and Technology (KIST) for the Institutional Program (2E26260).
Publisher Copyright:
© 2016 The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
Keywords
- black carbon
- carbon nanotube
- elemental carbon
- exposure assessment
- nanomaterial
- workplace
ASJC Scopus subject areas
- Public Health, Environmental and Occupational Health