Environ Int. 2020 Jan;134:105218. doi: 10.1016/j.envint.2019.105218. Epub 2019 Nov 9.
Urine selenium concentration is a useful biomarker for assessing population level selenium status.
Phiri FP1, Ander EL2, Lark RM3, Bailey EH4, Chilima B5, Gondwe J5, Joy EJM6, Kalimbira AA7, Phuka JC8, Suchdev PS9, Middleton DRS10, Hamilton EM11, Watts MJ12, Young SD13, Broadley MR14.
School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK; Department of Nutrition, HIV and AIDS, Ministry of Health, Lilongwe, Malawi. Electronic address: felixphiri8@gmail.com.
Inorganic Geochemistry, Centre for Environmental Geochemistry, British Geological Survey, NG12 5GG, UK. Electronic address: land@bgs.ac.uk.
School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK. Electronic address: murray.lark@nottingham.ac.uk.
School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK. Electronic address: liz.bailey@nottingham.ac.uk.
Community Health Sciences Unit, Ministry of Health, Private Bag 65, Lilongwe, Malawi.
Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK. Electronic address: edward.joy@lshtm.ac.uk.
Department of Human Nutrition and Health, Faculty of Food and Human Sciences, Bunda Campus, Lilongwe University of Agriculture and Natural Resources, P.O. Box 219, Lilongwe, Malawi. Electronic address: akalimbira@luanar.ac.mw.
School of Public Health and Family Medicine, College of Medicine, University of Malawi, Private Bag 360, Chichiri, Blantyre 3, Malawi.
Department of Pediatrics and Hubert Department of Global Health, Emory University, Atlanta, GA 30322, USA. Electronic address: psuchde@emory.edu.
Section of Environment and Radiation, International Agency for Research on Cancer, World Health Organization, Lyon, France. Electronic address: middletond@fellows.iarc.fr.
Inorganic Geochemistry, Centre for Environmental Geochemistry, British Geological Survey, NG12 5GG, UK. Electronic address: ellha@bgs.ac.uk.
Inorganic Geochemistry, Centre for Environmental Geochemistry, British Geological Survey, NG12 5GG, UK. Electronic address: mwatts@bgs.ac.uk.
School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK. Electronic address: scott.young@nottingham.ac.uk.
School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire LE12 5RD, UK. Electronic address: martin.broadley@nottingham.ac.uk.
Plasma selenium (Se) concentration is an established population level biomarker of Se status, especially in Se-deficient populations. Previously observed correlations between dietary Se intake and urinary Se excretion suggest that urine Se concentration is also a potentially viable biomarker of Se status. However, there are only limited data on urine Se concentration among Se-deficient populations. Here, we test if urine is a viable biomarker for assessing Se status among a large sample of women and children in Malawi, most of whom are likely to be Se-deficient based on plasma Se status. Casual (spot) urine samples (n = 1406) were collected from a nationally representative sample of women of reproductive age (WRA, n =741) and school aged children (SAC, n=665) across Malawi as part of the 2015/16 Demographic and Health Survey. Selenium concentration in urine was determined using inductively coupled plasma mass spectrometry (ICP-MS). Urinary dilution corrections for specific gravity, osmolality, and creatinine were applied to adjust for hydration status. Plasma Se status had been measured for the same survey participants. There was between-cluster variation in urine Se concentration that corresponded with variation in plasma Se concentration, but not between households within a cluster, or between individuals within a household. Corrected urine Se concentrations explained more of the between-cluster variation in plasma Se concentration than uncorrected data. These results provide new evidence that urine may be used in the surveillance of Se status at the population level in some groups. This could be a cost-effective option if urine samples are already being collected for other assessments, such as for iodine status analysis as in the Malawi and other national Demographic and Health Surveys.
Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.
Biomarkers; Biomonitoring; Micronutrient survey; Selenium status; Sub Saharan Africa; Urine
10.1016/j.envint.2019.105218