Bj. Canas et al., DETERMINATION OF ETHYL CARBAMATE IN ALCOHOLIC BEVERAGES AND SOY-SAUCEBY GAS-CHROMATOGRAPHY WITH MASS-SELECTIVE DETECTION - COLLABORATIVE STUDY, Journal of AOAC International, 77(6), 1994, pp. 1530-1536
A method using gas chromatography with mass selective detection for th
e determination of ethyl carbamate (EC; also known as urethane) in alc
oholic beverages and soy sauce was collaboratively studied by 17 labor
atories including authors' laboratories. The method uses prepacked col
umns for extraction of liquids with methylene chloride, and n-propyl c
arbamate as the internal standard. A practice sample and 6 samples of
distilled spirits, fortified wines, table wines, and soy sauces were a
nalyzed by each collaborator. Each matrix included blind duplicates of
incurred and fortified EC at 3 levels. Distilled spirits contained 50
-330 ng EC/g (ppb), fortified wine 40-160 ppb, table wine 10-50 ppb, a
nd soy sauce 15-70 ppb. The ranges of the repeatability relative stand
ard deviations, excluding outliers, were 4.03-6.63% for distilled spir
its, 4.01-5.05% for fortified wine, 3.94-6.73% for table wine, acid 4.
70-8.49% for soy sauce. The ranges of the reproducibility relative sta
ndard deviations, excluding outliers, were 8.53-9.49% for distilled sp
irits, 6.84-12.02% for fortified wine, 8.86-18.47% for table wine, and
13.87-27.37% for soy sauce. Recoveries of added EC ranged from 87 to
93%. Recoveries relative to reference values, labeled as the internal
standard, obtained by using gas chromatography/tandem mass spectrometr
y with a triple quadrupole mass spectrometer ranged from 89 to 100%.