ACETONE and METHYL ETHYL KETONE in urine (1) Acetone, CH3COCH3 (2) Methyl ethyl ketone, CH3COCH2CH3 METHOD: 8319, Issue 1
MW: 58.08 MW: 72.11
CAS: 67-64-1 CAS: 78-93-3
EVALUATION: FULL
OSHA & NIOSH: N/A Because data on exposure limits and guidelines may change over time, NIOSH recommends referring to the following sources for updated limits and guidelines [1-4].
8319
RTECS: AL3150000 RTECS: EL6475000 Issue 1: 28 October 2014
PROPERTIES: (1) bp 56.2 °C; d20 0.789 g/mL (2) bp 79.6 °C; d20 0.805 g/mL BIOLOGICAL INDICATOR OF: Exposure to (1) acetone (2) methyl ethyl ketone
SYNONYMS: (1) dimethyl ketone; 2-propanone; ketone propane; dimethyl formaldehyde; pyroacetic ether (2) 2-butanone; MEK; butanone; methyl acetone; butan-2-one; oxobutane SAMPLING SPECIMEN: Two urine samples (before and after exposure) VOLUME:
Fill a 20-mL amber VOA vial leaving minimal headspace
SHIPMENT: Ship in an insulated container with bagged refrigerant SAMPLE STABILITY:
Stable at least 30 days at 4 °C [5]
CONTROLS: Collect and pool urine from matched population of unexposed workers if possible, then refrigerate immediately ACCURACY RANGE STUDIED:
(1) 2.1 - 606 mg/L [5] (2) 2.2 - 617 mg/L [5]
ACCURACY:
(1) ± 11.5%, (2) ± 15.0%
BIAS:
(1) -0.0444, (2) -0.0782
OVERALL PRECISION (ŜrT):
(1) 0.0468 [5], (2) 0.0507
SAMPLE STABILITY:
MEASUREMENT TECHNIQUE:
GAS CHROMATOGRAPHY, FLAME IONIZATION DETECTOR, HEADSPACE
ANALYTES:
Acetone and methyl ethyl ketone
INJECTION VOLUME:
500 µL or timed (see measurement section)
TEMPERATURE -INJECTION: 180 °C -DETECTOR: 250 °C -COLUMN: 40 °C (4 min); 40 to 60 °C @ 3 °C/min; 60 to 220 °C @ 20 °C/min; 220 °C (2 min) CARRIER GAS:
Helium, at 15 psi head pressure
COLUMN:
Capillary, fused silica, 6% cyanopropylphenyl, 94% dimethylpolysiloxane, 75 m x 0.53 mm ID, 3.0 µm film thickness
CALIBRATION:
Analyte in control urine; 2-pentanone or other appropriate internal standard
ESTIMATED LOD: (1) 0.6 mg/L in pooled urine [5] (2) 0.6 mg/L in pooled urine [5]
(1) 101% (Day 30) [5] (2) 105% (Day 30) [5]
APPLICABILITY: This method can be used in the analysis of acetone and methyl ethyl ketone in urine specimens. These compounds may be found in the urine of individuals exposed to acetone and methyl ethyl ketone [6,7]. INTERFERENCES: Acetone is a metabolite of 2-propanol; MEK is a metabolite of 2-butanol. Exposure to 2-propanol or 2-butanol may result in increased acetone or MEK excretion, respectively [8,9]. Diabetes and fasting also produce elevated urinary acetone levels [10]. Ethanol reduces MEK metabolism and thus increases the MEK concentration in urine [11]. Gender differences and use of hormonal contraceptives have been shown to affect the metabolism and excretion of MEK [12]. OTHER METHODS: There are several commercially-available, direct-reading, dipstick-type tests that are non-specific for ketones in urine. These are often used in hospitals or by diabetic patients. The Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) has published a headspace method for a variety of alcohols and ketones in urine and blood [13].
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition
