BENZIDINE in urine
C12 H12 N2
MW: 184.24
METHOD: 8306, Issue 2
CAS: 92-87-5
8306
RTECS: DC9625000
EVALUATION: PARTIAL
Issue 1: 15 February 1984 Issue 2: 15 August 1994
BIOLOGICAL INDICATOR OF: exposures to benzidine and benzidine-based azo dyes.
SYNONYMS: [1,1'-biphenyl]-4,4'-diamine
BIOLOGICAL SAMPLING
MEASUREMENT
SPECIMEN:
urine, 2 to 3 h after exposure
TECHNIQUE:
GAS CHROMATOGRAPHY, ECD
VOLUME:
100 mL in polyethylene bottle
ANALYTE:
N,N'-diheptafluorobutyryl benzidine
INJECTION VOLUME:
3 µL, Grob type-splitless
PRESERVATIVE: 2 drops 12 N HCl after collection SHIPMENT: SAMPLE STABILITY: CONTROLS:
frozen and shipped in dry ice COLUMN:
15 m × 0.25-mm I.D. capillary; WCOT-SE-54
CARRIER GAS:
5 % methane in argon, 1 mL/min
unknown at least 3 urine specimens from nonexposed individuals per study; 1 per 10 samples
TEMPERATURE-INJECTOR: -DETECTOR: -COLUMN:
260°C 350°C 120°C for 2 min; 40°/min to 280°; hold 6 min
CALIBRATION:
solutions of benzidine in benzene with internal standard
QUALITY CONTROL:
spiked urine corrected for creatine content
RANGE:
10 to 1000 µg/L
RECOVERY:
92%
ESTIMATED LOD:
5 µg/L
PRECISION (Sr):
0.11
ACCURACY:
± 29%
APPLICABILITY: This procedure is useful for monitoring exposures to benzidine or benzidine-based azo dyes which are absorbed via the skin, lung, or gastrointestinal tract, and whose metabolites are benzidine or acetylbenzidine. This procedure qu antitates benzidine, N-acetylbenzidine, N,N'-diacetylbenzidine, as conjugates of benzidine. Maximum urinary levels occur 2 to 3 h after exposure [1]. INTERFERENCES: None known.
OTHER METHODS: This method is based on references [2] and [3].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94
