Urban respirable particles

Particulates are another source of respiratory irritation when inhaled. In urban environments, diesel exhaust particles and fly ash residue from power plant oil combustion are the main contributors of respirable particulates of less than 10 pm diameter (PM 10). These contain mixtures of lipo-philes and hydrophiles including various metals, acid salts, aliphatic hydrocarbons, PAHs, quinones, nitroaromatic hydrocarbons, andaldehydes. 151 Diesel combustion particulates contain large surface areas that can adsorb large quantities of organic compounds and deliver these to respiratory tract tissue. Other inhaled particulates can adhere to lung surfaces and adsorb and bond other vapors that are inhaled, thereby increasing their toxicities. PM2.5 particulates (those with diameters of less than 2.5 pm) that reach the lower respiratory tract as far as the alveoli are more toxic than PM 10 particulates of the same composition. 16 ... 

Bakand S, Winder C, Khalil C et al (2006) An experimental in vitro model fm dynamic direct exposure of human cells to airborne contaminants. Toxicol Lett 165 1-10 Bartoli CR, Wellenius GA, Diaz EA et al (2009) Mechanisms of inhaled fine particulate air pollution-induced arterial blood pressure changes. Environ Health Perspect 117 361-366 Becker S, Soukup JM, Sioutas C et al (2003) Response of human alveolar macrophages to ultrafine, fine, and coarse urban air pollution particles. Exp Lung Res 29 29-44 Beckett WS, Chalupa DF, Pauly-Brown A et al (2005) Comparing inhaled ultrafine versus fine zinc oxide particles in healthy adults a human inhalation study. Am J Respir Crit Care Med 171 1129-1135... 

Mauad T, Rivero DHRF, de Oliveira RC et al (2008) Chronic exposure to ambient levels of urban particles affects mouse lung development. Am J Respir Crit Cate Med 178 721-728 Mazzarella G, Ferraraccio F, Prati MV et al (2007) Effects of diesel exhaust particles on human lung epithelial cells An in vitro study. Respir Med 101 1155-1162 McClellan RO (2000) Particle interactions with the respiratory tract. In Gehr P, Heyder J (eds) Particle-lung interactions, 1st edn. Marcel Dekker, New York Mills NL, Ttimqvist H, Gonzalez MC et al (2007) Ischemic and thrombotic effects of dilute diesel-exhaust inhalation in men with coronary heart disease. N Engl J Med 357 1075-1082 Mills NL, Robinson SD, Fokkens PHB et al (2008) Exposure to concentrated ambient particles does not affect vascular function in patients with coronary heart disease. Environ Health Perspect 116 709-715... 

Table 5.1 presents some illustrative data gathered for California sites for lead content of resuspended materials in the respirable particulate fraction as a function of type of dust source. The levels range from 0.002% to 0.3% with agricultural soils presenting with the lowest lead concentrations, as might be expected. An urban (Fresno, CA) test site showed a level of 0.3%, consistent with the relationship of dust and soil lead content determining resuspended particle lead content. 

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