Laboratory and Field Comparisons of Air Sampling Methods for 1,6-Hexamethylene Diisocyanate
Public Deposited- Last Modified
- February 28, 2019
- Creator
-
Thomasen, Jennifer M.
- Affiliation: Gillings School of Global Public Health, Department of Environmental Sciences and Engineering
- Abstract
- The published literature on evaluation of sampling devices and methods for determining workers' exposure to diisocyanate-containing compounds is conflicting and most of the methods have not been tested in both a laboratory and occupational setting. The objective of this study was to evaluate the performance of commonly used sampling devices for 1,6-hexamethylene diisocyanate (HDI) in both the laboratory and occupational field setting. Polystyrene (PS) and polypropylene (PP) cassettes with treated filters, IOM cassettes, OSHA Method 42 cassettes, and IsoChek® cassettes were evaluated in the laboratory setting. Recovery of HDI mass using either toluene (HDI/TOL) or acetonitrile (HDI/ACN)as solvents was determined. In the laboratory, the IOM and 25-mm PP cassette types recovered the most HDI mass (>77%) while the IsoChek® performed the worst recovering <16% of HDI mass. The reactivity of HDI with different filter housings and sampling materials was determined by spiking pure HDI, HDI/TOL, or HDI/ACN onto filter housings and sampling materials. Pure HDI and HDI/TOL were most reactive with PS and the reaction of HDI with sampling materials was amplified by the presence of a non-polar solvent (i.e., TOL). The sampling efficiencies of 1- and 2-stage PP and PS cassettes were compared to an impinger in the occupational setting by spraying fast- or slow-drying clear coat containing HDI polyisocyanates above the samplers. No significant difference was observed in HDI monomer recovery between PP and PS samplers. However, significant difference (p<0.05) was observed in the recovery of HDI oligomers between 1- and 2-stage cassettes and between fast- and slow-drying clear coats. The 1-stage cassettes recovered more HDI monomer and oligomer when a fast-drying clear coat was applied. In summary, this study provides evidence that sampling losses may occur due to the reactivity of HDI with sampling materials or with polyols in automotive paint overspray. We also demonstrate the importance of performing experiments in both the laboratory and occupational setting. Experiments performed in the occupational setting indicate that the type of clear coat used during spray-painting activities should be considered when selecting a sampler for monitoring exposure to HDI.
- Date of publication
- December 2007
- DOI
- Resource type
- Rights statement
- In Copyright
- Advisor
- Ball, Louise
- Nylander-French, Leena A.
- Leith, David
- Degree
- Master of Science in Public Health
- Academic concentration
- Environmental Health Sciences
- Degree granting institution
- University of North Carolina at Chapel Hill
- Graduation year
- 2007
- Language
- Deposit record
- e00f1df6-6c31-41ba-867b-150d86a8c8cb
Relations
- Parents:
This work has no parents.