Determination of U in environmental samples by single extraction chromatography coupled to triple-quadrupole inductively coupled plasma-mass spectrometry.

In order to measure trace U and U/U in environmental samples with a high matrix effect, a novel and simple method was developed that makes the digestion and purification procedures compatible with advanced triple-quadrupole inductively coupled plasma-mass spectrometry. A total dissolution of sample with HF + HNO + HClO was followed by chromatographic separation with a single resin column containing normal type DGA resin (N,N,N',N'-tetra-n-octyldiglycolamide) as the extractant system. The analytical accuracy and precision of U/U ratios, measured as UO/UO, were examined by using the reference materials IAEA-135, IAEA-385, IAEA-447, and JSAC 0471. The low method detection limit (3.50 × 10 Bq kg) makes it possible to perform routine monitoring of environmental U due to global fallout combined with the Fukushima Daiichi Nuclear Power Plant accident fallout (>10 Bq kg). Finally, the developed method was successfully applied to measure U/U ratios and U activities in soil samples contaminated by the accident. The low U/U atom ratios ((1.50-13.5) × 10) and U activities ((2.25-14.1) × 10 mBq kg) indicate U contamination was mainly derived from global fallout in the examined samples.