An Approach to Area Sampling and Analysis for Total Isocyanates in Workplace Air

Details

• Personal Author:
  Key-Schwartz, Rosa J. ; Tucker, Samuel P.
• Description:
  An approach to sampling and analysis for total isocyanates (monomer plus any associated oligomers of a given isocyanate) in workplace air has been developed and evaluated. Based on a method developed by the Occupational Health Laboratory, Ontario Ministry of Labour, Ontario, Canada, isocyanates present in air are derivatized with a fluorescent reagent, tryptamine, in an impinger and subsequently analyzed via high-performance liquid chromatography (HPLC) with fluorescence detection. Excitation and emission wavelengths are set at 275 and 320 nm, respectively. A modification to the Ontario method was made in the replacement of the recommended impinger solvents (acetonitrile and 2,2,4-trimethylpentane) with dimethyl sulfoxide (DMSO). DMSO has the advantages of being compatible with reversed-phase HPLC and not evaporating during sampling, as do the more volatile solvents used in the Ontario method. DMSO also may dissolve aerosol particles more efficiently during sampling than relatively nonpolar solvents. Several formulations containing diisocyanate prepolymers have been tested with this method in the laboratory. This method has been issued as National Institute for Occupational Safety and Health (NIOSH) Method 5522 in the first supplement to the fourth edition of the NIOSH Manual of Analytical Methods. This method is recommended for area sampling only due to possible hazards from contact with DMSO solutions containing isocyanate derivatives. The limits of detection are 0.1 µg/sample for 2,4-toluene diisocyanate, 0.2 µg/sample for 2,6-toluene diisocyanate, 0.3 µg/sample for methylene bisphenyl diisocyanate, and 0.2 µg/sample for 1,6-hexamethylene diisocyanate. [Description provided by NIOSH]
• Subjects:
  Chemistry Chemistry, Analytic Chromatography Isocyanates Occupational Health Safety Workplace
• Keywords:
  Analytical-chemistry Analytical-methods Analytical-processes Chromatographic-analysis Fluorescence-spectrometry Sampling Sampling-equipment Sampling-methods Statistical-analysis Workplace-monitoring Workplace-studies

  More +
• ISSN:
  0002-8894
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  Ohio ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DPSE - Division of Physical Sciences and Engineering
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  200-207
• Volume:
  60
• Issue:
  2
• NIOSHTIC Number:
  nn:20027767
• Citation:
  Am Ind Hyg Assoc J 1999 Mar/Apr; 60(2):200-207
• CAS Registry Number:
  2,2,4-Trimethylpentane (CAS RN 540-84-1) ; Acetonitrile (CAS RN 75-05-8) ; Dimethyl sulfoxide (CAS RN 67-68-5)
• Federal Fiscal Year:
  1999
• Peer Reviewed:
  True
• Source Full Name:
  American Industrial Hygiene Association Journal
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:ed364e6fe834640546425ec93a9c0b256b3ccea2080a1f376161b08ff6ab3f5d2ec3082da5dbbcda801482901641de498b82049f08abc73980477eb6d6938e2a
• Download URL:
  https://stacks.cdc.gov/view/cdc/197654/cdc_197654_DS1.pdf
• File Type:
  [PDF - 339.73 KB ]