Page:NIOSH Manual of Analytical Methods - 8306.pdf/1

 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