Page:NIOSH Manual of Analytical Methods - 5509.pdf/1

 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