@misc{10481/77827,
year = {2022},
month = {9},
url = {https://hdl.handle.net/10481/77827},
abstract = {Background: Toenails are commonly used as biomarkers of exposure to zinc (Zn), but there is scarce information
about their relationship with sources of exposure to Zn.
Objectives: To investigate the main determinants of toenail Zn, including selected sources of environmental
exposure to Zn and individual genetic variability in Zn metabolism.
Methods: We determined toenail Zn by inductively coupled plasma mass spectrometry in 3,448 general population
controls from the MultiCase-Control study MCC-Spain. We assessed dietary and supplement Zn intake
using food frequency questionnaires, residential proximity to Zn-emitting industries and residential topsoil Zn
levels through interpolation methods. We constructed a polygenic score of genetic variability based on 81 single
nucleotide polymorphisms in genes involved in Zn metabolism. Geometric mean ratios of toenail Zn across
categories of each determinant were estimated from multivariate linear regression models on log-transformed
toenail Zn.
Results: Geometric mean toenail Zn was 104.1 μg/g in men and 100.3 μg/g in women. Geometric mean toenail Zn
levels were 7 % lower (95 % confidence interval 1–13 %) in men older than 69 years and those in the upper
tertile of fibre intake, and 9 % higher (3–16 %) in smoking men. Women residing within 3 km from Zn-emitting
industries had 4 % higher geometric mean toenail Zn levels (0–9 %). Dietary Zn intake and polygenic score were
unrelated to toenail Zn. Overall, the available determinants only explained 9.3 % of toenail Zn variability in men
and 4.8 % in women.
Discussion: Sociodemographic factors, lifestyle, diet, and environmental exposure explained little of the individual
variability of toenail Zn in the study population. The available genetic variants related to Zn metabolism
were not associated with toenail Zn.},
organization = {Instituto de Salud Carlos III},
organization = {Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP)},
organization = {FEDER funds-a way to build Europe	PI08/1770	
PI09/0773	
PI12/00715	
PI09/1903	
PI09/2078	
PI09/1662	
PI11/01403	
PI12/00150	
PI12/00488	
PI15/00914	
PI17CIII_00034},
organization = {Fundacion Marques de Valdecilla grant	API 10/09},
organization = {Junta de Andalucia	2009-S0143},
organization = {Conselleria de Sanitat of the Generalitat Valenciana	AP061/10},
organization = {Regional Government of the Basque Country},
organization = {Principality of Asturias},
organization = {University of Oviedo},
organization = {Spanish Ministry of Economy and Competitiveness Juan de la Cierva de Incorporacion	IJCI-2014-20900	
Instituto de Salud Carlos III},
publisher = {Elsevier},
keywords = {Toenail},
keywords = {Environmental exposures},
keywords = {Biomarker},
keywords = {Zinc},
keywords = {Single nucleotide polymorphism},
keywords = {Polygenic score},
title = {Toenail zinc as a biomarker: Relationship with sources of environmental exposure and with genetic variability in MCC-Spain study},
doi = {10.1016/j.envint.2022.107525},
author = {Gutiérrez González, Enrique and Salcedo Bellido, Inmaculada},
}