Page:NIOSH Manual of Analytical Methods - 5516.pdf/1

5516

SYNONYMS: 2,4-: 4-methyl-1,3-benzenediamine; 2,4-diaminotoluene

SYNONYMS: 2,6-: 2-methyl-1,3-benzenediamine; 2,6-diaminotoluene

SAMPLER IMPINGER (solution of 1-(2-methoxyphenyl)piperazine in toluene, 15 mL) FLOW RATE 1 L/min VOL-MIN: -MAX: 30L @ 10 µg/m3 500L SHIPMENT: routine SAMPLE STABILITY: at least 2 weeks @ 25 °C in the dark [1] FIELD BLANKS: 2 to 10 field blanks per set ACCURACY RANGE STUDIED: not studied BIAS: not determined OVERALL PRECISION: not determined ACCURACY: not determined

TECHNIQUE: HPLC, UV DETECTION ANALYTES: 2,4- and 2,6-bisacetamidotoluene INJECTION VOLUME: 10 μL MOBILE PHASE: programmed; sodium acetate in acetonitrile/water at pH 6.0; 1.0 mL/min; ca. 20°C COLUMN: 10 cm × 8-mm octadecylsilylated silica (C18), 5-μm particle size, in Waters RCM-100 radial compression module CALIBRATION: standard solution of analytes in methanol RANGE: 0.3 to 3 μg per sample [1] ESTIMATED LOD: 0.1 μg per sample [1] PRECISION (${\displaystyle {\overline {S_{t}}}}$): 0.06 @ 0.74 to 0.89 μg per sample [1]

APPLICABILITY: The working range is 3 to 30 μg/m³ for a 100-L air sample. This method, based on that of Warwick et al. for isocyanates [2], determines 2,4- and 2,6-toluenediamine in air in the presence of isocyanates. Samples from polyurethane foam plants were analyzed simultaneously for 2,4- and 2,6-toluenediamine and 2,4- and 2,6-toluene diisocyanate [1].

INTERFERENCES: m-Phenylenediamine interferes in the determination of 2,4-toluenediamine.

OTHER METHODS: Holdren et al. [3] reported a similar method using N-(4-nitrobenzyl)propylamine in toluene for sampling and HPLC with electrochemical detection. Other methods are: (a) absorb on Tenax GC, desorb in toluene, GC [4]; (b) absorb on silica gel, desorb in 2-butanone, GC [5]; (c) sample in aqueous acid, work up, GC of free amines [6] or bis(heptafluoro­ butyryl)amides [7,8]; (d) sample in ethanolic KOH, workup, LC of free amine [9,10] or GC of bis(pentafluoropropionyl) amides [11]; (e) sample with sulfuric acid-coated filter, work up, GC of bis(heptafluorobutyryl)amides [12]. Some of these methods [3,9—11] can be used for the simultaneous determination of toluenediamines and toluene diisocyanates.