Outdoor air pollution, climatic changes and allergic bronchial asthma

Abstract

Both the prevalence and severity of respiratory allergic diseases such as bronchial asthma have increased in recent years. Among the factors implicated in this "epidemic" are indoor and outdoor airborne pollutants. Urbanisation with its high levels of vehicle emissions and Westernised lifestyle parallels the increase in respiratory allergy in most industrialised countries, and people who live in urban areas tend to be more affected by the disease than those of rural areas. In atopic subjects, exposure to air pollution increases airway responsiveness to aeroallergens. Pollen is a good model with which to study the interrelationship between air pollution and respiratory allergic diseases. Biological aerosols carrying antigenic proteins, such as pollen grains or plantderived paucimicronic components, can produce allergic symptoms. By adhering to the surface of these airborne allergenic agents, air pollutants could modify their antigenic properties. Several factors influence this interaction, i.e., type of air pollutant, plant species, nutrient balance, climatic factors, degree of airway sensitisation and hyperresponsiveness of exposed subjects. However, the airway mucosal damage and the impaired mucociliary clearance induced by air pollution may facilitate the penetration and the access of inhaled allergens to the cells of the immune system, and so promote airway sensitisation. As a consequence, an enhanced immunoglobulin E-mediated response to aeroallergens and enhanced airway inflammation favoured by air pollution could account for the increasing prevalence of allergic respiratory diseases in urban areas.

The toxicology of climate change: Environmental contaminants in a warming world

“…However, a number of studies suggest that the toxicity of ozone and PM will be exacerbated with global warming, and some of these data support that older adults will be especially vulnerable (Bell et al, 2007;Confalonieri et al, 2007;Dominici et al, 2006;Fiala et al, 2003;IPCC, 2007c;Katsouyanni et al, 1993;Knowlton et al, 2004;Koken et al, 2003;Mauzerall et al, 2005;Ordonez et al, 2005;Rainham and Smoyer-Tomic, 2003;Ren and Tong, 2006). Other potential interactions between climate change and toxicant exposure include increased susceptibility to pathogens (Abadin et al, 2007;Nagayama et al, 2007;Smialowicz et al, 2001) and aeroallergens (D'Amato et al, 2002;Diaz-Sanchez et al, 2003;Epstein, 2005;Janssen et al, 2003). Table 1 summarizes important interactions between climate change, toxicant exposures, and human health.…”

“…The effects of contaminants on vulnerable subpopulations warrant further study, although there is evidence that older individuals will be more susceptible to climate-air pollutant interactions (Fiala et al, 2003;Koken et al, 2003;Ordonez et al, 2005). In addition, low-income populations, infants, children, and chronically ill individuals may be especially susceptible to climate sensitive outcomes linked to interactions between pollutant exposures and changes in vector-borne and allergic disease (D'Amato et al, 2002;Diaz-Sanchez et al, 2003;Epstein, 2005;Haines et al, 2006;Janssen et al, 2003).…”

“…In addition to changes in vector-borne disease, the incidences and severity of allergic disease are rising, especially in industrialized countries (D'Amato et al, 2002;Diaz-Sanchez et al, 2003). Asthma prevalence has quadrupled in the United States since 1980.…”

Climate change and respiratory diseases

“…The main cause of adverse health effects seems to be combustion-derived ultrafine particles that incorporate organic and transition metal components. Diesel exhaust particles (DEPs), composed of 80% ultrafine particles, and associated polycyclic aromatic hydrocarbons impact on airborne allergens, increasing exposure effects, concentration and allergenic biological activity [38]. Several studies have demonstrated effects of ozone over respiratory symptoms, including shortness of breath, wheezing and coughing, lower respiratory tract infections, acute and transient decreases in lung function, increased airway responsiveness, airway injury and inflammation, and systemic oxidative stress [39].…”

Die Achse Umwelt‐Erreger‐Wirt bei übertragbaren und nicht übertragbaren Krankheiten: Jüngste Fortschritte in der experimentellen und klinischen Forschung

“…Wir hatten bereits gezeigt, dass ultrafeine Partikel, wie sie in Diesel-Abgasen vorkommen, allergisches Asthma in einem Mausmodell verstärken [18,19]. Insgesamt gibt es eine solide Datenbasis dafür, dass industrielle und verkehrsbedingte Luftschadstoffe die Inzidenz atopischer Erkrankungen erhöhen und in ihrer Ausprägung verschärfen (Review in [20]). Allerdings wirken sich viele dieser Faktoren ebenso auf den Allergenträger, z.…”