Page:NIOSH Manual of Analytical Methods - 5029.pdf/1

 4,4'-METHYLENEDIANILINE

CH2(C6H4NH2)2

MW: 198.27

METHOD: 5029, Issue 2

5029

CAS: 101-77-9

RTECS: BY5425000

EVALUATION: PARTIAL

OSHA : no PEL NIOSH: lowest feasible; carcinogen ACGIH: 0.1 ppm (skin); suspected human carcinogen (1 ppm = 8.11 mg/m 3 @ NTP)

PROPERTIES:

Issue 1: 15 August 1990 Issue 2: 15 August 1994

solid; MP 92 °C; BP 399 °C; VP 0.2 x 10 -7 kPa (1.5 x 10 -7 mm Hg) @ 25 °C

SYNONYMS: p,p'-diaminodiphenylmethane; MDA.

SAMPLING

MEASUREMENT

SAMPLER:

FILTER (acid-treated glass fiber, 37-mm)

TECHNIQUE:

HPLC, UV AND ELECTROCHEMICAL DETECTION

FLOW RATE:

1 to 2 L/min

ANALYTE:

4,4'-methylenedianiline (MDA)

VOL-MIN: -MAX:

10 L @ 0.1 ppm 1000 L

EXTRACTION:

0.1 N KOH In methanol

SHIPMENT:

transfer filter to glass vial; extract with 4 mL 0.1 N methanolic KOH before shipping

INJECTION VOLUME:

25 µL

SAMPLE STABILITY:

stable at least 60 days @ 20 °C [1]

FIELD BLANKS:

2 to 10 field blanks per set

MEDIA BLANKS:

at least 3 per set

ACCURACY RANGE STUDIED:

not studied

BIAS:

not determined

ˆ ): not determined OVERALL PRECISION (S rT ACCURACY:

not determined

MOBILE PHASE:

0.1 N sodium acetate in acetonitrile/70% H 2O @ 1 mL/min

30%

COLUMN:

C 18 column, 4-µm particle size

DETECTOR:

UV, 245 nm; electrochemical (ECHD), glassy carbon electrode at +0.75 to +0.85 V vs. Ag/AgCl electrode

CALIBRATION:

MDA in 0.1 N methanolic KOH

RANGE: UV: ECHD:

0.3 to 5 µg per sample [1] 0.025 to 0.5 µg per sample [1]

ESTIMATED LOD: 0.12 to 1.2 µg per sample [4] PRECISION (Sr):

0.027

ESTIMATED LOD: UV: 0.12 µg per sample ECHD: 0.007 µg per sample [1]

APPLICABILITY: The working range is 0.025 ppb to 1.2 ppm (0.0002 to 10 mg/m 3) for a 100-L air sample, and the method is applicable to STEL measurements. The method is specific for MDA and the use of UV and electrochemical detectors in serie s gives greater reliability to the analysis, and allows a wide measurement range. The method has been applied to wipe samp les.

INTERFERENCES: 4,4'-Diphenylmethane diisocyanate (MDI) will interfere owing to its conversion to MDA on the acid-treated glass fiber filter. Other aromatic amines do not interfere.

OTHER METHODS: Methods with acetylation, and the determination of the acetic anhydride derivative of MDA either by HPLC/UV [2] or by GC/EC (OSHA Method 57) [3] have been reported.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94