An FTIR Investigation of Isocyanate Skin Absorption Using In Vitro Guinea Pig Skin

Details

• Personal Author:
  Bello D ; Boeniger, Mark F. ; Liu Y ; Redlich CA ; Smith, Thomas J. ; Streicher, Robert P. ; Woskie SR
• Description:
  Isocyanates may cause contact dermatitis, sensitization and asthma. Dermal exposure to aliphatic and aromatic isocyanates can occur in various exposure settings. The fate of isocyanates on skin is an important unanswered question. Do they react and bind to the outer layer of skin or do they penetrate through the epidermis as unreacted compounds? Knowing the kinetics of these processes is important in developing dermal exposure sampling or decontamination strategies, as well as understanding potential health implications such exposure may have. In this paper the residence time of model isocyanates on hairless guinea pig skin was investigated in vitro using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectrometry. Model isocyanates tested were octyl isocyanate, polymeric hexamethylene diisocyanate isocyanurate (pHDI), polymeric isophorone diisocyanate isocyanurate (pIPDI) and methylenediphenyl diisocyanate (MDI). Isocyanates in ethyl acetate (30 microL) were spiked directly on the skin to give 0.2-1.8 micromol NCO cm(-2) (NCO = -N[double bond, length as m-dash]C[double bond, length as m-dash]O), and absorbance of the isocyanate group and other chemical groups of the molecule were monitored over time. The ATR-FTIR findings showed that polymeric isocyanates pHDI and pIPDI may remain on the skin as unreacted species for many hours, with only 15-20% of the total isocyanate group disappearing in one hour, while smaller compounds octyl isocyanate and MDI rapidly disappear from the skin surface (80+% in 30 min). Isocyanates most likely leave the skin surface by diffusion predominantly, with minimal reaction with surface proteins. The significance of these findings and their implications for dermal exposure sampling and isocyanate skin decontamination are discussed. [Description provided by NIOSH]
• Subjects:
  Animals Asthma Asthma, Occupational Dermatitis Hypersensitivity Isocyanates Occupational Health Safety Skin Skin Absorption Skin Diseases

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• Keywords:
  Animal-studies Bronchial-asthma Contact-dermatitis Dermatosis In-vitro-studies Models Sampling Sensitization Skin-absorption
• ISSN:
  1464-0325
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Connecticut ; Massachusetts ; Ohio ; OSHA Region 1 ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DART - Division of Applied Research and Technology
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  8
• Issue:
  5
• NIOSHTIC Number:
  nn:20030221
• Citation:
  J Environ Monit 2006 May; 8(5):523-529
• Contact Point Address:
  Harvard School of Public Health, Exposure, Epidemiology & Risk Program, Landmark Center, West/404F, 401 Park Drive, Boston, MA 02215, USA
• Email:
  dbello@hsph.harvard.edu
• Federal Fiscal Year:
  2006
• NORA Priority Area:
  Research Tools and Approaches: Exposure Assessment Methods
• Performing Organization:
  Yale University, New Haven, Connecticut
• Peer Reviewed:
  True
• Start Date:
  20020930
• Source Full Name:
  Journal of Environmental Monitoring
• End Date:
  20060929
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:f5dfcacbdac43e929fbaf9366fa2cbbe1333da44677fa8f668d35c102bef8646a0d7ef901776febe0aaf6867fbf0c57add40adf8bad54dd085dfdeadc868b8d2
• Download URL:
  https://stacks.cdc.gov/view/cdc/190971/cdc_190971_DS1.pdf
• File Type:
  [PDF - 649.28 KB ]