Inductively coupled plasma mass spectrometric determination of molybdenum in urine from a Danish population†

Abstract

Molybdenum creatinine levels in urine were measured in 128 Danish inhabitants by ICP-MS in order to establish reference intervals of molybdenum in urine for the Danish population as a part of the EURO-TERVIHT project (Trace Element Reference Values in Human Tissues). The Mo concentration was determined using the isotopes ⁹⁵Mo and ⁹⁸Mo. The values measured based on ⁹⁸Mo were about 2% lower than those calculated using ⁹⁵Mo, a negligible difference in the context of reference values. The limit of detection was 0.2 µg l^–1, the precision was 8.6% and the recovery of added NIST 1643c certified reference material was 94%. The distribution of the data, with and without correction for creatinine concentration, was log-normal. The mean concentration measured was 42.5 µg l^–1, (3.89 µg Mo mmol^–1 creatinine) using ⁹⁵Mo and 41.5 1 µg l^–1 (3.81 µg Mo mmol^–1 creatinine) using ⁹⁸Mo, with the 95% parametric reference intervals 10.0–124.0 µg l^–1 (0.89–11.50 µg Mo mmol^–1 creatinine) and 9.6–122.6 µg l^–1 (0.84–11.47 µg Mo mmol^–1 creatinine), respectively. The difference between men and women reached the level of significance only after the values were corrected for the creatinine concentration. There was no influence of age on the Mo concentration. Specific effects of different food and beverage intakes could not be demonstrated, with the exception of a positive correlation between butter consumption and Mo concentration.