Page:NIOSH Manual of Analytical Methods - 8319.pdf/2

 ACETONE and METHYL ETHYL KETONE in urine: METHOD 8319, Issue 1, dated 28 October 2014 - Page 2 of 6

REAGENTS:

EQUIPMENT:

1.	Pooled control urine collected from unexposed workers* 2.	Acetone (≥99%) and MEK (≥99%) stock solution: Prepare by diluting the appropriate amounts of the pure analyte in water.* 750 µL in 10 mL gives ~60 mg/mL of each. Be certain to use the densities and purity factors when calculating the exact concentrations. [5] 3.	Internal standard solution: Dilute 80 mg of 2-pentanone (≥99%) in enough water to make 1.0 L (80 mg/L).* Alternatively, 100 µL can be added to 1 L which gives roughly the same concentration. 4.	Water, ASTM Type II [14] 5.	Helium, purified 6.	Hydrogen, prepurified 7.	Air, filtered, prepurified

1.	Bottles, polyethylene screw-top, 125-mL 2.	Volatile organic analysis (VOA) vials, 20-mL, amber, polytetrafluoroethylene (PTFE) caps 3.	Gas chromatograph, with flame ionization detector (FID), data system and column (p. 8319-1) 4.	Headspace autosampler 5.	Bagged refrigerant 6.	Pipette, 10-mL, plastic or serological 7.	Headspace vials, 20-mL, PTFE/Butyl septa, aluminum crimp cap 8.	Microliter syringes, 10-µL, 100-µL, 1-mL 9.	 Volumetric flask, 10-mL

SPECIAL PRECAUTIONS: Wear gloves, lab coat, and safety glasses while handling all chemicals and human urine products. Disposable plastic, glass, and paper (pipet tips, gloves, etc.) that contact urine should be placed in a biohazard container. Standard precautions should always be used when handling bodily fluids and/or extracts of bodily fluids [15]. Handle urine samples and urine extracts using proper gloves. Acetone and MEK are highly flammable liquids. All work should be performed in a fume hood since both chemicals are respiratory irritants and may depress the central nervous system at high exposure levels. SAMPLING: 1.	Collect urine in a 125-mL polyethylene bottle or other suitable container. Collect at least two urine samples from each worker. Collect one sample before exposure and one sample after exposure. NOTE: It is important to avoid contamination of the urine samples by making sure that samples are collected in a clean area away from the source(s) of exposure and under hygienic conditions (after washing hands.) 2.	For each sample, immediately transfer from the 125-mL polyethylene bottle enough urine to fill a 20-mL amber VOA vial such that a minimal headspace is left. Cap the containers tightly. When the VOA vial is inverted no air bubbles should be present. Refrigerate after collection. 3.	Collect and pool urine from unexposed workers to be used for controls. Refrigerate after collection. 4.	Ship the VOA vials and pooled control urine in a refrigerated, well-insulated container. Store refrigerated upon receipt. SAMPLE PREPARATION: 5.	Allow urine to reach room temperature. 6.	Pipet 10.0 mL of urine from the VOA vial into a 20-mL headspace vial. 7.	Add 0.5 mL of the internal standard solution. 8.	Cap vial immediately.
 * See SPECIAL PRECAUTIONS

NIOSH Manual of Analytical Methods (NMAM), Fifth Edition