Health & Environmental Research Online (HERO)

Print Feedback Export to File
Journal Article 
Twenty-four-hour urinary trace element excretion: Reference intervals and interpretive issues 
Sieniawska, CE; Jung, LC; Olufadi, R; Walker, V 
In Press 
Annals of Clinical Biochemistry
ISSN: 0004-5632
EISSN: 00045632 
BACKGROUND: Introduction of inductively coupled plasma mass spectrometry (ICP-MS) into clinical laboratories has led to an increasing application of analyses to risk assessment for toxicity from environmental exposure to trace elements, and in occupational monitoring. Interpretation of results from random urine samples may be problematic and measurement of excretion over 24 h is sometimes preferable. Recent reference data are sparse. METHODS: Twenty-four-hour urine samples from 111 healthy adults from the renal stones clinic in Southampton, UK, were analysed for 31 trace elements using ICP-MS and for zinc using atomic absorption spectroscopy. Non-parametric 0.95 coverage intervals were determined for trace element excretion per 24 h and as a ratio to creatinine, for the full study cohort and separately for men (n = 77) and women (n = 34). RESULTS: Beryllium was undetectable in 95% of samples, bismuth in 87% and uranium in 75%. In comparison with published ranges, reference intervals for this cohort were higher for molybdenum, tin and vanadium, and for arsenic due to inclusion of fish arsenicals. Aluminium, chromium, iron, lead and mercury were lower. In our cohort, 24-h excretion of 17 elements was significantly higher in men than in women. However, when expressed as trace element to creatinine ratios, the situation reversed strikingly. Because of their lower creatinine excretion, ratios for 18 elements were significantly higher for women. CONCLUSIONS: New adult reference intervals were obtained for 24-h urine trace element excretion. Trace element:creatinine ratios must be used cautiously, with separate ranges for men and women. 
• Arsenic Hazard ID
     1. Initial Lit Search
          Considered New
     2. Lit Search Updates through Oct 2015
     4. Considered through Oct 2015
     6. Cluster Filter through Oct 2015
     7. Other Studies through Oct 2015
• Arsenic (Inorganic)
     1. Literature
          Toxline, TSCATS, & DART
          Web of Science
          Lit search updates through Oct 2015
     3. Hazard ID Screening
          Other potentially supporting studies
• Methylmercury
     Literature Search: Jan 1998 - March 2017
          Food Studies
          Web of Science
     ADME Search: Jan 1990 - Nov 2018
          Results with mercury
• Uranium
     Merged reference set
     Secondary Refinement
          Retained for manual screening
     Additional Resource
          Exposure levels
     Uranium Literature Search Update 3/2017
• Vanadium Compounds - Problem Formulation
     Literature Search: Jan 2010 - Mar 2019
     Combined data set
          Dataset for title/abstract screening
               Excluded- PECO criteria not met (TIAB)