AUTHOR=Calderón-Garcidueñas Lilian , Chávez-Franco Diana A. , Luévano-Castro Samuel C. , Macías-Escobedo Edgar , Hernández-Castillo Ariatna , Carlos-Hernández Esperanza , Franco-Ortíz Agustina , Castro-Romero Sandra P. , Cortés-Flores Mónica , Crespo-Cortés Celia Nohemí , Torres-Jardón Ricardo , Stommel Elijah W. , Rajkumar Ravi Philip , Mukherjee Partha S. ,  Research Universidad del Valle de México UVM Group , Márquez Celedonio Félix Guillermo , Vacaseydel-Aceves Nora B. , Carrillo-Ibarra Sandra , Roura-Velasco Jorge , Vázquez-Cruz Joaquín , Juárez-Herrera- Y-Cairo Lucero Aída , Fierro-Fimbres Noelia Guadalupe , Águila-Castellanos Karina , Arballo-Romero Abel , Burruel-DeLaCruz Nilza , Castelar-Ibarra Kristel , Cuéllar-Figueroa Beatriz , Moreno-Barceló Priscilla , Romero-Romero José Luis , Sedano-Benítez Jaquelinne , Moreno-Monreal Viviana , Dávila-Ortiz Fernanda , Ramírez-Sánchez Silvia , García-Rojas Edgar , Brito-Aguilar Rafael , Jiménez-Hernández Luis E. , Molina-Olvera Gabriela , Vega-Riquer José Manuel , García-Alonso Griselda , Rodríguez-Version Geidy , Olmos-García Francisco Xavier 

TITLE=Metals, Nanoparticles, Particulate Matter, and Cognitive Decline

JOURNAL=Frontiers in Neurology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2021.794071

DOI=10.3389/fneur.2021.794071

ISSN=1664-2295

ABSTRACT=<p>Exposure to metals is ubiquitous and emission sources include gasoline, diesel, smoke from wildfires, contaminated soil, water and food, medical implants, waste recycling facilities, subway exposures, and occupational environments. PM<sub>2.5</sub> exposure is associated with impaired cognitive performance, neurobehavioral alterations, incidence of dementia, and Alzheimer's disease (AD) risk. Heavy-duty diesel vehicles are major emitters of metal-rich PM<sub>2.5</sub> and nanoparticles in Metropolitan Mexico City (MMC). Cognitive impairment was investigated in 336 clinically healthy, middle-class, Mexican volunteers, age 29.2 ± 13.3 years with 13.7 ± 2.4 years of education using the Montreal Cognitive Assessment (MoCA). MoCA scores varied with age and residency in three Mexican cities with cognition deficits impacting ~74% of the young middle-class population (MoCA ≤ 25). MMC residents ≥31 years (<inline-formula><mml:math id="M1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mover accent="false" class="mml-overline"><mml:mrow><mml:mtext>x</mml:mtext></mml:mrow><mml:mo accent="true">¯</mml:mo></mml:mover></mml:math></inline-formula>46.2 ± 11.8 y) had MoCA <inline-formula><mml:math id="M2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mover accent="false" class="mml-overline"><mml:mrow><mml:mtext>x</mml:mtext></mml:mrow><mml:mo accent="true">¯</mml:mo></mml:mover></mml:math></inline-formula>20.4 ± 3.4 vs. low pollution controls 25.2 ± 2.4 (<italic>p</italic> &lt; 0.0001). Formal education years positively impacted MoCA total scores across all participants (<italic>p</italic> &lt; 0.0001). Residency in PM<sub>2.5</sub> polluted cities impacts multi-domain cognitive performance. Identifying and making every effort to lower key pollutants impacting neural risk trajectories and monitoring cognitive longitudinal performance are urgent. PM<sub>2.5</sub> emission control should be prioritized, metal emissions targeted, and neuroprevention interventions implemented early.</p>