A Test Procedure for the Determination of (2-Methoxyethoxy)acetic Acid in Urine from Jet Fuel-Exposed Mice.
ABSTRACT A test procedure for the determination of (2-methoxyethoxy)acetic acid (MEAA) was adapted and applied to urine samples from jet fuel (JP-8)-exposed mice using capillary gas chromatography with a mass selective detector (MSD). MEAA is a metabolite and proposed biomarker for exposure to 2-(2-methoxyethoxy)ethanol, a glycol ether component in the formulation of JP-8. The collected urine samples were spiked with deuterated butoxyacetic acid internal standard, and extracted with ethyl acetate, and esterified with ethanol and sulfuric acid, and the esters of the glycol ethers were extracted with methylene chloride. The chromatographic conditions used easily separate the MEAA ethyl ester from interferences within mouse urine. The application of this procedure to urine samples collected from mice demonstrated that MEAA was detectable after oral (2000 mg/kg) or dermal (50 mu L) exposure for 7 days to JP-8 at levels as high as 8.5 or 6.5 mu g/mL, respectively. This pilot demonstration indicated that total urinary MEAA was a viable biomarker for the two routes of JP-8 exposure in laboratory mice.