BENZIDINE
(C6H4NH2)2
MW: 184.23
METHOD: 5509, Issue 2
5509
CAS: 92-87-5
RTECS: DC9625000
EVALUATION: FULL
OSHA : carcinogen (29 CFR 1910.1010) NIOSH: carcinogen (29 CFR 1910.1010) ACGIH: carcinogen (skin)
Issue 1: 15 May 1989 Issue 2: 15 August 1994
PROPERTIES: solid; MP 127 C; BP 400 °C
SYNONYMS: [1,1'-biphenyl]-4,4'-diamine; p-diaminodiphenyl.
SAMPLING SAMPLER:
FILTER (13-mm glass fiber)
FLOW RATE:
0.2 L/min
VOL-MIN: -MAX:
20 L @ 10 µg/m 3 100 L
SHIPMENT:
ship benzidine samples in dry ice
SAMPLE STABILITY:
11 days @ -15 °C [1]
BLANKS:
2 to 10 field blanks per set
MEASUREMENT TECHNIQUE:
HPLC, UV DETECTION
ANALYTE:
benzidine or 3,3'-dichlorobenzidine
DESORPTION:
0.5 mL 0.17% (v/v) triethylamine in methanol; stand 60 min
INJECTION VOLUME:
10 µL
MOBILE PHASE:
60% methanol/40% water;
FLOW RATE:
1.5 mL/min; ambient temperature
COLUMN:
µBondapak C 18, 10-µm particles, 30 cm x 4-mm
DETECTOR:
UV, 254 nm
CALIBRATION:
solutions of analyte(s) in eluent
RANGE:
0.2 to 7 µg per sample
ACCURACY RANGE STUDIED:
21 to 63 µg/m 3 [1]
BIAS:
- 3.0%
ˆ ): 0.07 [1] OVERALL PRECISION (S rT
ESTIMATED LOD: 0.05 µg per sample [1]
ACCURACY:
PRECISION (Sr):
± 13.7%
≤0.07 [1]
APPLICABILITY: The working range for benzidine or 3,3'-dichlorobenzidine is 4 to 200 µg/m 3 for a 50-L air sample. Benzidinium sulfate and 3,3'-dichlorobenzidine dihydrochloride will be collected and converted to benzidine and 3,3'-dichlorobenzidi ne, respectively, during sample preparation.
INTERFERENCES: Aniline interferes in the determination of benzidine but may be resolved [2]. 4,4'-Methylenebis(2-chloroaniline) interferes in the determination of 3,3'-dichlorobenzidine [1]. A number of compounds were shown not to interfere [1,2] (see NOTE 2, step 12).
OTHER METHODS: This combines and replaces P&CAM 243 and P&CAM 246 [3].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94
