Release of Crystalline Silica Nanoparticles During Engineered Stone Fabrication (Dataset)

Details

• Personal Author:
  Dozier, Alan K. ; Ku BK ; Kulkarni P ; Qi C ; Rishi K ; Thompson D ; Vogiazi V ; Wang C ; Zervaki O
• Description:
  Inhalation exposure to respirable crystalline silica (RCS) during fabrication of engineered stone-based kitchen countertops has been on the rise in recent years and has become a significant occupational health problem in the United States and globally. Little is known about the presence of nano-crystalline silica (NCS), i.e., particles below 100 nm. We present a methodology to quantify the crystalline silica content in the sub-100 nm size fraction of the aerosol released during engineered stone fabrication using X-ray diffraction (XRD) and Fourier transform Infrared (FT-IR) spectroscopy. Aerosol was generated in test chamber designed per EN 1093-3 and sampled using cascade impactors. XRD and FT-IR analysis showed the presence of both a-quartz (15 - 60 %) and cristobalite (10 - 50 %) polymorphs in all size fractions. With increasing particle size, the cristobalite content increased. 70 % of the total aerosol mass in the sub-100 nm fraction was found to be crystalline silica, qualitatively confirmed by electron diffraction and electron energy loss spectroscopy. Presence of other minerals was detected in all size fractions; no polymeric resin binder was detected in the sub-100 nm fraction. Although, the sub-100 nm fraction was about 1 % of the aerosol mass, it accounted for 4 - 24 % of the aerosol surface area based on total lung deposition. If the surface area is a more relevant exposure metric, the assessment of efficacy of current engineering control systems using mass as an exposure metric may not provide adequate protection. [Description provided by NIOSH]
• Subjects:
  Aerosols Occupational Health Particulate Matter Respiratory System Safety Silicon Dioxide
• Keywords:
  Aerosol Particles Crystalline Silica Inhalation Studies Nanocrystals Nanoparticles Particle Size Stone Products
• DOI:
  https://doi.org/10.26616/NIOSHRD-1106-2024-0
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Dataset
• Genre:
  Research Dataset
• Place as Subject:
  Chicago Region [OSHA] ; Ohio
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division ; DFSE - Division of Field Studies and Engineering
• Topic:
  Workplace Safety & Health
• Location:
  North America
• NIOSHTIC Number:
  nn:20070505
• Citation:
  Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Research Dataset RD-1106-2024-0, 2025 Jan; :dataset
• Contact Point Address:
  Health Effects Laboratory Division (HELD), National Institute for Occupational Safety and Health (NIOSH), Cincinnati, OH
• CAS Registry Number:
  Quartz (SiO2) (CAS RN 14808-60-7)
• Federal Fiscal Year:
  2025
• NORA Priority Area:
  Construction ; Manufacturing
• Peer Reviewed:
  False
• Source Full Name:
  Release of crystalline silica nanoparticles during engineered stone fabrication
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:d580f93f3ec5b99504771e5c5f0aa4f0acb16ba27faefbd3aa1cf23b37937ae70e6affd799e85b2f2a01245c892d66f4e021d986e00284fdbfccecea04e0e41c
• Download URL:
  https://stacks.cdc.gov/view/cdc/208703/cdc_208703_DS1.pdf
• File Type:
  [PDF - 135.63 KB ]