Real-Time Measurement of Airborne Carbon Nanotubes in Workplace Atmospheres

Details

• Personal Author:
  Kulkarni P ; Zheng L
• Description:
  With growing applications of carbon nanomaterials, there is a concern over health risks presented by inhalation of carbon nanotube (CNT) aerosol in workplace atmospheres. Current methods used for CNT aerosol measurement lack selectivity to specific form of carbonaceous component or allotrope of interest. Moreover, the detection limits of these methods are also inadequate for short-term monitoring. Here, we describe, for the first time, a near real-time, fieldportable instrument for selective quantification of airborne CNT concentration. The approach uses an automated cyclical scheme involving collect-analyze-ablate steps to obtain continuous near realtime measurement using Raman spectroscopy. The method achieves significantly lower detection limits by employing corona-assisted particle microconcentration for efficient coupling with laser Raman spectroscopy. A combination of techniques involving (i) use of characteristic Raman peaks, (ii) distinct ratio of disordered and graphitic peaks, and (iii) principal component classification and regression is employed to identify and quantify the specific form of the aerosolized carbonaceous nanomaterial. We show that the approach is capable of selectively quantifying trace single-walled CNT in the presence of interfering agents such as diesel particulate matter. The detection limit of the method for the single-walled CNT studied in this work was 60 ng m-3, corresponding to a 10 min aerosol collection period, which is significantly lower than that for the NIOSH Method 5040 (approx. 0.15 ug m.3 for an 8-h collection on a 25 mm filter at 4 L min-1), a commonly used method for elemental carbon. We demonstrate the automated realtime capability of this field-portable method by continuously measuring a transient single-walled CNT aerosol. [Description provided by NIOSH]
• Subjects:
  Aerosols Air Pollutants, Occupational Air Pollution Occupational Health Particulate Matter Safety
• Keywords:
  Airborne Particulates Air Quality Monitoring Carbon Nanotubes CNT Monitors Nanomaterials
• ISSN:
  0003-2700
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  91
• Issue:
  20
• NIOSHTIC Number:
  nn:20057540
• Citation:
  Anal Chem 2019 Oct; 91(20):12713-12723
• Contact Point Address:
  Pramod Kulkarni, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Cincinnati, Ohio 45226
• Email:
  pskulkarni@cdc.gov
• CAS Registry Number:
  Carbon nanotubes (CAS RN 308068-56-6)
• Federal Fiscal Year:
  2020
• NORA Priority Area:
  Oil and Gas Extraction ; Manufacturing
• Peer Reviewed:
  True
• Source Full Name:
  Analytical Chemistry
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:99911437ada5b61756d95d1b5119bc0f7ba6e7bd7a86d5658b50d17ca7c5875bb90b6fd02f31e7cdc2eb9e8c3896f1550a47aecda361223165f51f9a2647b74b
• Download URL:
  https://stacks.cdc.gov/view/cdc/214858/cdc_214858_DS1.pdf
• File Type:
  [PDF - 1.92 MB ]