Biological mechanisms by which inhaled ambient air particles may produce health effects is an important focus of research. Studies of ambient particle toxicity need to consider both pulmonary and systemic effects. The toxic potential of ambient particles is dependent upon their constituents which may be quite variable in many urban settings. A number of biologic measurements can be used to indicate the toxic potential of particles including their capability to produce active oxygen radicals and induce pro-inflammatory cytokines. Local pulmonary responses involving cytokines and/or chemokines may be the basis of systemic inflammation. These local responses may also be involved in mechanisms which facilitate the systemic redistribution of soluble or insoluble organic or inorganic constituents of particles. Such components may then give rise to inflammatory responses in other organs. Cardiac responses to inhaled particles appear to be particularly important in defining effects which may lead to death. Non-inflammatory mechanisms also need to be considered. These include responses mediated via the autonomic nervous system as well as the potential for direct effects on the endothelium of the vasculature in vital organs. Effects on coagulation and the local interaction of soluble particle constituents in cell function at sites far removed from the lung are other mechanisms by which inhaled particles may produce adverse systemic responses. Delineating these mechanisms in responses to inhaled particles at ambient levels is a major challenge for inhalation toxicologists.
Learning Objectives: Describe the scientific evidence for health effects of particulate air pollution
Keywords: Air Pollutants, Air Quality
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.