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

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 microgram 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 long-normal. The mean concentration measured was 42.5 micrograms l-1, (3.89 micrograms Mo mmol-1 creatinine) using 95Mo and 41.5 micrograms l-1 (3.81 micrograms Mo mmol-1 creatinine) using 98Mo, with the 95% parametric reference intervals 10.0-124.0 micrograms l-1 (0.89-11.50 micrograms Mo mmol-1 creatinine) and 9.6-122.6 micrograms l-1 (0.84-11.47 micrograms 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.