Page:NIOSH Manual of Analytical Methods - 8305.pdf/1

 PHENOL and p-CRESOL in urine

(1) C6H5OH (2) CH3C6H4OH

MW: MW:

94.11 108.14

METHOD: 8305, Issue 2

CAS: 108-95-2 CAS: 106-44-5

8305

RTECS: SJ3325000 RTECS: GO6475000

EVALUATION: PARTIAL

BIOLOGICAL INDICATOR OF:

Issue 1: 15 May 1985 Issue 2: 15 August 1994

exposure to phenol, benzene, and p-cresol.

SYNONYMS: (1) phenol: carbolic acid (2) p-cresol: 4-methylphenol SAMPLING SPECIMEN:

two spot urine samples (before and after exposure)

VOLUME:

50 to 100 mL in polyethylene screw-cap bottle containing preservative

MEASUREMENT METHOD:

GAS CHROMATOGRAPHY, FID

ANALYTE:

phenol and p-cresol

TREATMENT:

acid hydrolysis; extraction

PRESERVATIVE: few crystals of thymol

INJECTION VOLUME:

5 µL

SHIPMENT:

TEMPERATURE-INJECTION: -DETECTOR: -COLUMN:

180 °C 200 °C 4 min @ 120 °C; 16 °C/min; 4 min @ 190 °C

SAMPLE STABILITY:

CONTROLS:

freeze urine; ship in dry ice in an insulated container

stable for 4 days @ 25 °C and for 3 months @ -4 °C

COLUMN:

3 m x 2-mm ID glass, 2% diethylene glycol adipate/Anakrom Q, 60/80 mesh

collect urine from unexposed workers; pool and freeze the control urine

CARRIER GAS:

N 2, 25 mL/min

CALIBRATION:

analyte in control urine; nitrobenzene internal standard

RANGE:

2 to 300 µg phenol/mL urine; 2 to 500 µg p-cresol/mL urine

ESTIMATED LOD: 0.5 µg/mL urine RECOVERY:

(1) 94% @ 15 mg/mL; (2) 95% @ 50 µg/mL

PRECISION (Sr):

(1) 0.128; (2) 0.091

ACCURACY:

(1) ± 31.0%; (2) ± 22.8%

APPLICABILITY: Phenol and p-cresol occur normally in urine. This method is useful in screening workers exposed to phenol, p-cresol, and benzene. The chief metabolite of benzene is phenol [1]. Workers exposed 8 h to 25 ppm benzene excreted abou t 150 mg phenol/L urine [2].

INTERFERENCES: o-Phenylphenol has a GC retention time similar to that of phenol. A careful work history/questionnaire is suggested.

OTHER METHODS: This method replaces P&CAM 330 [3]. A nonspecific colorimetric method yields 50% higher phenol concentrations with normal urine than does this method [4].

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