Investigation of Particle Size-Related Artifacts in Analyte Quantification of Particulate Samples Using Infrared Spectroscopy Methods

Details

• Journal Article:
  Journal of Aerosol Science
• Personal Author:
  Rishi, Kabir ; Zervaki, Orthodoxia ; Ku, Bon-Ki ; Pugh, Nicholas ; Wang, Chen ; Vogiazi, Vasileia ; Kulkarni, Pramod
• Description:
  Infrared absorption spectroscopy is commonly used to quantify chemicals in the particulate phase for environmental and occupational aerosol exposure measurements. Unlike gas-phase analyte quantification, the analytical figures of merit depend on the characteristics of the particulate phase, in particular the aerosol size distribution. In the Mie scattering regime, where the particle size is comparable to the incident infrared wavelength, the bias in analyte quantification can depend on particle size. This error may depend on how well the size distribution of the aerosol matches with that of the reference material used to calibrate the method. While the impact of packing densities, and spectral interferences from the substrate and other minerals in the aerosol has been assessed in previous work, the impact of aerosol size distribution has not been explored. In this work, the Lorenz-Mie solution to Maxwell's equation was used to determine the bias in mass quantification of quartz in typical occupational aerosols for which the IR method is commonly used. Our experimental findings were benchmarked with the Lorenz-Mie solution using model spherical polystyrene particles. Practical deviations due to the asymmetric shape of quartz particles size-fractionated using different cascade impactors are presented and compared with literature studies on quartz aerosols. The expected bias in analyte quantification using different quartz standard reference materials relative to NIST SRM 1878a was assessed. The implications on quartz quantification due to differences in aerosol size distribution at different locations in the coal mine, granite quarries, and during construction activities such as stone finishing and grinding are presented and discussed.
• Subjects:
  Aerosols Occupational Health Particulate Matter Safety Silicon Dioxide
• Keywords:
  Aerosols; Aerosol Particles; Spectroscopes; Particle Aerodynamics; Particle Size Analysis; Exposure Assessment; Particulate Sampling Methods; Analytical Instruments; Quartz; Author Keywords: Aerosol; Infrared Spectroscopy; Lorenz-Mie Scattering; Size-related Artifacts
• Source:
  J Aerosol Sci 2026 Jan; 191:106669
• ISSN:
  0021-8502
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  Ohio ; South Dakota ; Chicago Region [OSHA] ; Denver Region [OSHA]
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  12 pdf pages
• Volume:
  191
• NIOSHTIC Number:
  nn:20071317
• Contact Point Address:
  Pramod Kulkarni, Centers for Disease Control and Prevention (CDC), National Institute for Occupational Safety and Health (NIOSH), Health Effects Laboratory Division (HELD), 1090 Tusculum Ave, Cincinnati, OH, 45226, USA
• Email:
  PSKulkarni@cdc.gov
• CAS Registry Number:
  Quartz (SiO2) (CAS RN 14808-60-7)
• Federal Fiscal Year:
  2026
• NORA Priority Area:
  Construction ; Manufacturing
• Peer Reviewed:
  True
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:9ad149708c069e578ef2f60c00f6856be8ed78b58a6058b7aab10590cbfb369a7305b774644c832b0961bf7cda40f2c22e9a43081abc65a5ad69a9d27cb97748
• Download URL:
  https://stacks.cdc.gov/view/cdc/258793/cdc_258793_DS1.pdf
• File Type:
  [PDF - 2.86 MB ]