**4. Conclusions**

Our study was the first to evaluate a large amount of inorganic elements in relation to stroke, including 19 inorganic elements belonging to the ATSDR's priority pollutant list and 26 rare earth elements and other elements used in the manufacturing of high tech devices. The findings of this study indicated that patients with stroke had higher levels of lead and lower levels of bismuth, cerium, gallium and osmium. These findings provided new evidence of the potential association of dysregulated heavy metals and other elements in patients with stroke, whose ability to cross the blood brain barrier has been previously suggested. While lead was as a risk factor for stroke, barium, gold, cerium and gallium appeared as protective factors for the disease. Given the high persistence of these elements in the environment and the significant technological dependence on them, future studies are needed to elucidate the potential sources of exposure and disclose the mechanisms of action of the identified elements in the prevalence and prognosis of stroke.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2305-6304/8/3/66/s1. Supplementary material 1: Limit of quantification (LOQ)a of elements of inorganic elements included in the study, Supplementary material 2: Bivariate correlations between inorganic elements and continuous demographic variables, Supplementary material 3: Bivariate correlations between inorganic elements and categorical variables. Significant associations are highlighted in bold. Data reported in ng/mL, except for copper, zinc and iron (ug/mL), Supplementary material 4a: Bivariate Spearman correlations between the inorganic elements among controls (*n* = 83), Supplementary material 4b: Bivariate Spearman correlations between the inorganic elements among cases (*n* = 92).

**Author Contributions:** Conceptualization, F.M.-E., L.D.B. and L.A.H.-H.; methodology, M.Z. and Á.R.-H. formal analysis, L.A.H.-H.; data curation, F.M.-E., F.F.-F. and M.E.S.-J.; writing—original draft preparation, L.A.H.-H.; writing—review and editing, O.P.L. and L.D.B.; supervision, O.P.L.; project administration, L.D.B. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** The authors would also like to thank all participants, without whom this study would not have been possible.

**Conflicts of Interest:** The authors declare that they have no competing interests.
