@article{10902/26553,
year = {2022},
url = {https://hdl.handle.net/10902/26553},
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 = {Funding: The study was supported by the “Acción Transversal del Cáncer”, approved on the Spanish Ministry Council on the 11 October 2007, by the Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP), by the Instituto de Salud Carlos III grants, co-funded by 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;by the Fundación Marqués de Valdecilla grant API 10/09, by the Consejería de Salud of the Junta de Andalucía grant 2009-S0143, by the Conselleria de Sanitat of the Generalitat Valenciana grant AP061/10, by the Regional Government of the Basque Country, by the Fundación Caja de Ahorros de Asturias, by the University of Oviedo and by the Spanish Ministry of Economy and
Competitiveness Juan de la Cierva de Incorporación grant IJCI-2014-20900.},
publisher = {Elsevier},
publisher = {Environment International
 Volume 169, November 2022, 107525},
title = {Toenail zinc as a biomarker: Relationship with sources of environmental exposure and with genetic variability in MCC-Spain study},
author = {Gutiérrez-González, Enrique and Fernández-Navarro, Pablo and Pastor-Barriuso, Roberto and García-Pérez, Javier and Castaño-Vinyals, Gemma and Martín-Sánchez, Vicente and Amiano, Pilar and Gómez Acebo, Inés and Guevara, Marcela and Fernández Tardón, Guillermo and Salcedo-Bellido, Inmaculada and Moreno, Víctor and Pinto Carbó, Marina and Alguacil, Juan and Marcos-Gragera, Rafael and Gómez Gómez, Jesús Humberto and Gómez Ariza, José Luis and García Barrera, Tamara and Varea Jiménez, Elena and Alonso Molero, Jessica},
}