title: In vitro biological effects of airborne PM₂.₅ and PM₁₀ from a semi-desert city on the Mexico-US border.
abstract: Compelling evidence indicates that exposure to urban airborne particulate matter (PM) affects health. However, how PM components interact with PM-size to cause adverse health effects needs elucidation, especially when considering soil and anthropogenic sources. We studied PM from Mexicali, Mexico, where soil particles contribute importantly to air pollution, expecting to differentiate in vitro effects related to PM-size and composition. PM samples with mean aerodynamic diameters ≤2.5μm (PM(2.5)) and ≤10μm (PM(10)) were collected in Mexicali (October 2005-March 2006) from a semi-urban (expected larger participation of soil sources) and an urban (predominately combustion sources) site. Samples were pooled by site and size, analyzed for elemental composition (particle-induced X-ray emission) and tested in vitro for: induction of human erythrocytes membrane disruption (hemolysis) (colorimetrically); inhibition of cell proliferation (ICP) (crystal violet) and TNFα/IL-6 secretion (ELISA) using J774.A1 murine monocytic cells; and DNA degradation using Balb/c3T3 cell naked DNA (electrophoretically). Results of PM elemental composition principal component analysis were used in associating cellular effects. Sixteen elements identified in PM grouped in two principal components: Component(1) (C(1)): Mg, Al, Si, P, Cl, K, Ca, Ti, V, Cr, Fe, and Component(2) (C(2)): Cu, Zn. Hemolysis was predominately induced by semi-urban-PM(10) (p<0.05) and was associated with urban-PM(10)C(1) (r=0.62, p=0.003). Major ICP resulted with semi-urban PM(2.5) (p<0.05). TNFα was mainly induced by urban samples regardless of size (p<0.05) and associated with urban-PM(2.5)C(2) (r=0.48, p=0.02). Both PM(10) samples induced highest DNA degradation (p<0.05), regardless of location. We conclude that PM-size and PM-related soil or anthropogenic elements trigger specific biological-response patterns.
authors.affiliation: Investigación Básica, Instituto Nacional de Cancerología, México, DF 14080, Mexico. osornio@ualberta.ca
authors.forename: Alvaro R
authors.initials: AR
authors.lastname: Osornio-Vargas
authors.forename: Jesús
authors.initials: J
authors.lastname: Serrano
authors.forename: Leonora
authors.initials: L
authors.lastname: Rojas-Bracho
authors.forename: Javier
authors.initials: J
authors.lastname: Miranda
authors.forename: Claudia
authors.initials: C
authors.lastname: García-Cuellar
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Reyna
authors.forename: Geraldine
authors.initials: G
authors.lastname: Flores
authors.forename: Miriam
authors.initials: M
authors.lastname: Zuk
authors.forename: Margarito
authors.initials: M
authors.lastname: Quintero
authors.forename: Inés
authors.initials: I
authors.lastname: Vázquez
authors.forename: Yesennia
authors.initials: Y
authors.lastname: Sánchez-Pérez
authors.forename: Tania
authors.initials: T
authors.lastname: López
authors.forename: Irma
authors.initials: I
authors.lastname: Rosas
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000737:chemistry / Q000633:toxicity*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D016207:Cytokines / Q000378:metabolism; D003889:Desert Climate; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects*; D008800:Mexico; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis / Q000737:chemistry / Q000633:toxicity*; D014481:United States
chemical_list: D000393:Air Pollutants; D016207:Cytokines; D052638:Particulate Matter