Comparison of Two Methods for Sampling Hexamethylene Diisocyanate Biuret Aerosol: A Chamber Study.
Liu-Y; Bello-D; Redlich-CA; Stowe-MH; Cullen-MR; Walsh-FX; Young-F; Woskie-SR
Am J Respir Crit Care Med 2003 Apr; 167(7):A716
Hexamethylene diisocyanate (HDI) biuret aerosol exposure is an important cause of occupational asthma. Control in the workplace is hampered by lack of agreement on the best metric for quantifying exposure and a uniform analytical method. A new NIOSH method 5525 has recently been developed that uses the Institute of Occupational Medicine sampler, a single quartz filter and 1-(9-anthracenylmethyl)piperazine (MAP) as derivatizing agent. The purpose of this study was to compare this method with the established ISOCHEK (ISO) cassette method in measuring HDI biuret aerosol. A closed exposure chamber was used to generate an HDI biuret (Desmodur N-l00) aerosol with overall concentrations varied over an equivalent HDI monomer range of 4 to 70 ppb, as measured by the Autostep portable equipment. Twenty-seven side-by-side samples were taken from the chamber using both methods. Samples were analyzed by high performance liquid chromatography. For HDI monomer, MAP method found higher levels than ISO method [GM (GSD:ug/m3): 80.1(2.2) vs. 61.3(2.0), p<0.005, n=27]. For HDI biuret aerosol, MAP method found lower levels [75.4(2.7) vs. 99.0(3.3),p<0.05, n=25]. When exposure was expressed as total reactive isocyanate group (TRIG) mass, no difference was found between MAP and ISO methods [65.6(2.0) vs. 61.2(2.1), p>0.05, n=25]. MAP method was also found best correlated with ISO method for biuret aerosol (ISO = 1.06MAP, R2=0.78). These results suggest that measurements of HDI aerosol by MAP and ISO methods were similar although the data were variable. The MAP method potentially provides an easier alternative for the measurement of HDI and HDI-based polyisocyanate aerosol.
Aerosols; Occupational-exposure; Analytical-methods; Workplace-studies; Aerosol-particles; Sampling-methods; Analytical-instruments
110-82-7; 822-06-0; 108-19-0
Abstract; Conference/Symposia Proceedings
Disease and Injury: Asthma and Chronic Obstructive Pulmonary Disease
American Journal of Respiratory and Critical Care Medicine, 2003 International Conference, The American Thoracic Society, Seattle, WA, May 16-21, 2003
Yale University, New Haven, CT