Variability of lead in urine and blood in healthy individuals

Gerd Sallsten; Dag G Ellingsen; Balazs Berlinger; Stephan Weinbruch; Lars Barregard

doi:10.1016/j.envres.2022.113412

Variability of lead in urine and blood in healthy individuals

Environ Res. 2022 Sep;212(Pt C):113412. doi: 10.1016/j.envres.2022.113412. Epub 2022 May 4.

Authors

Gerd Sallsten¹, Dag G Ellingsen², Balazs Berlinger³, Stephan Weinbruch⁴, Lars Barregard⁵

Affiliations

¹ Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg & Sahlgrenska University Hospital, Sweden. Electronic address: gerd.sallsten@amm.gu.se.
² National Institute of Occupational Health, Oslo, Norway.
³ National Institute of Occupational Health, Oslo, Norway; Department of Animal Hygiene, Herd Health and Mobile Clinic, University of Veterinary Medicine, István U. 2., H-1078, Budapest, Hungary.
⁴ National Institute of Occupational Health, Oslo, Norway; Institute of Applied Geosciences, Technical University Darmstadt, Schnittspahnstr. 9, D-64287, Darmstadt, Germany.
⁵ Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg & Sahlgrenska University Hospital, Sweden.

PMID: 35523277
DOI: 10.1016/j.envres.2022.113412

Abstract

Background: Lead is a non-essential toxic trace element. Lead in blood (BPb) is the most common biomarker of lead exposure but lead in urine (UPb) has also been used. There is, however, limited data on the variability of UPb in the general population and the association with BPb.

Objectives: Our aims were to assess variability of lead in repeated blood and urine samples. The diurnal variation of UPb was also examined as well as associations with BPb.

Methods: We established an openly available biobank including 60 healthy non-smoking individuals, 29 men and 31 women, 21-64 years of age (median 31 years), with repeated sampling of blood and urine. Timed urine samples were collected at six fixed time points in two 24 h periods, about one week apart, and adjusted for creatinine and specific gravity (SG). BPb and UPb were analyzed by inductively coupled plasma mass spectrometry. The within- and between-individual variabilities and intra-class correlation coefficients (ICCs; ratios of the between-individual to total observed variances) were calculated using mixed-effects models.

Results: The ICCs for UPb samples were mostly above 0.5, when adjusted for creatinine or SG, and higher for overnight samples compared with daytime samples. The highest ICCs were obtained for BPb (ICC = 0.97) and for urine samples corrected for dilution by SG or creatinine. The ICC was 0.66 for overnight samples adjusted for creatinine. High correlations with BPb were found for 24 h UPb (r_s = 0.77) and overnight samples, e.g. r_s = 0.74 when adjusted for SG. There was diurnal variation of UPb with lowest excretion rate in overnight samples. There was also a significant association between the Pb excretion rate and urinary flow rate.

Conclusions: In addition to BPb, UPb adjusted for creatinine or SG seems to be a useful biomarker for exposure assessment in epidemiological studies.

Keywords: Blood; Diurnal variation; Intra-class correlation; Lead; Urine; Variability.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Biomarkers
Creatinine / urine
Female
Humans
Lead*
Male
Trace Elements*

Substances

Biomarkers
Trace Elements
Lead
Creatinine