ISOCYANAT ES, TOTA L (MAP): METHO D 5525, Issue 1, dated 15 March 2003 - Page 10 of 17 Limit of Detection/Limit of Quantification: The limit of detection (LOD) and limit of quantification (LOQ) were determined by spiking several MAPderivatized m onom ers onto MAP filters in the range of 0.01 to 3.0 nanoe quiva lents, e xtrac ting the filters with acetonitrile, acetylating and ana lyzing by HP LC. The m etho d LO D is e stim ated to be abo ut 0.2 nan oeq uivalen ts NCO per sam ple and the LOQ 0.5 nanoequivalents NCO per sample for both fluorescence height and UV area [8]. As an example, these are equivalent to an LOD of 17 ng per sample and an LOQ of 42 ng per sample for HDI monom er. Bello et al. estimated the method detection limit to be 8 ng per sam ple for HDI monom er [9]. The instrumental LOD is substantially lower than the method detection limit, but is not achievable because of low levels of reagent-derived artifacts that are present in the chromatogram . Occ asionally an analyte peak will coelute with a relatively large artifact peak, raising the LOD and LOQ substan tially. Our experience is that IPDI m onom er isom ers coelute with som e HD I oligom ers when bo th are present in a sa m ple. T his m akes the IPD I m ono m ers, which are typically pres ent at very low levels, unm eas urab le.
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NIOSH [1998]. Chapter K: De term ination of a irborne isocyanate exp osu re. In: O’Connor PF, ed. NIOSH Ma nua l of Analytical Metho ds, 4 th ed. C incinn ati, OH : U.S. Dept. of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH). DHHS/NIOSH Publication #98-119. Streicher RP, Reh CM, Key-Schwartz RJ, Schlecht PC, Cassinelli ME, O’Connor PF [2000]. Determ ination of airborne isocyanate exposure: considerations in method selection. American Ind ustrial Hyg iene Ass ociation Journal 61: 544-556. NIOSH [1994]. Method 55 22, Isocyanates. In: Eller PM, Cassinelli ME, eds. NIOSH Man ua l of Analytical Me thod s, 4 th ed. Cincinnati, OH: U .S. Dept. of He alth an d Hum an S ervices, P ublic H ealth Service, Centers for D isease C ontrol and Prevention, National Institute for Occ upational Safety and Health, DHHS (NIOSH) Publication No. 94-113. NIOSH [1994]. Method 5521, Isocyanates, Monom eric. Issue 2. In: Eller PM, Cassinelli ME, eds. NIOSH Manual of A nalytica l Methods, 4 th ed. Cincinnati, OH: U.S. Dept. of Health and Human Services, Pub lic Health Service, Cente rs for Diseas e Contro l and P reve ntion, Na tional Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113. Streicher RP, Arnold JE, Ernst MK, Coope r CV [1996]. Development of a novel derivatization reagent for the sampling and analysis of total isocyanate group in air and comparison of its pe rform anc e with tha t of several estab lished rea gents . Am erican Industrial H ygiene As sociation Journal 57: 905-913. For inform ation o n availability of MAP, contact Robert Streicher, NIOSH M ail Stop R-7, 4676 Co lum bia Parkw ay, Cincinnati, OH 45226, tel: 513-841-4296 , E-m ail: rstreicher@c dc.gov. Be llo D, Streicher RP, W oskie SR [2002]. Eva luation of the NIO SH Draft Method 5525 for Determination of the Tota l Re active Iso cyanate G roup (TRIG) in A ir in Autobody Repair Shops. Journal of Environmental Monitoring 4: 351-360. Streicher RP, Ernst MK, W illiamson GY. Unpublished data. Cincinnati, OH: U.S. Dept. of Health and Hum an Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. Bello D, Streicher RP, Liu YC, Sparer J, Youngs F, W oskie SR [2002]. Field comparison of impingers and treated filters for sampling of total aliphatic isocyanates using the MAP reagent. American Ind ustrial Hyg iene Ass ociation Journal 63: 790-796. Streicher RP, Ernst MK, W illiamson G Y [2000]. Use of pH-gradient HPLC for the analysis of di- and polyisocyanates. Presented at the 32 nd Central Regional Meeting of the Am erican C hem ical Society, Covington, KY, May 18. Unless otherwise specified, properties were obtained from the Aldrich H andbook o f Fine Ch em icals and Laboratory Equipment, 2000-2001. W oods G [1987]. The IC I Po lyureth anes Book . New York, NY: IC I Po lyureth anes and John W iley & Sons, Inc. Inte rnatio nal Ch em ical Safety Card # 0278, http://hazard.c om /m sds/m f/cards/file/02 78.htm l.
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition
