Respiratory Changes due to Long-term Exposure to Urban Levels of Air Pollution: Outcome

In: Pulmonary function

21 May 2014

The results of the present investigation indicate that humans living in a polluted neighborhood of Sao Paulo had histopathologic evidence of damage to the small airways when compared with a matched population living in cleaner environments. The polluted area was Guarulhos, an industrial area of the Sao Paulo metropolitan area. Air pollution in this region is produced by both automotive and industrial sources. Unfortunately, only measurements of par-ticulated material with an aerodynamic diameter <10 (xm (PM10), S02, and black smoke were available. The physical and chemical nature of the particulates (PM10) in Guarulhos or of the clean areas is not available. We only have data on PM10 characteristics in downtown Sao Paulo. However, we believe that this information, although desirable, is not fundamental, since we did not aim to ascribe to any agent the responsibility of the observed alteration. Our purpose was much more simple, ie, to verify whether people living in regions with historical differences in air pollution levels do exhibit changes on lung histopathology. Recent epidemiologic studies have observed consistent and coherent associations between cardiopulmonary morbidity/mortality and inhalable particles (usually measured as PM10). In the Guarulhos area, PM10 attains annual concentrations ranging from 80 to 100 μg/m (24 h mean) between 1991 and 1995, a level of pollution that was demonstrated to be associated with increased mortality in Sao Paulo. The presence of inflammatory alterations in the lungs of individuals living in Guarulhos seems to be consistent with results of recent epidemiologic studies, showing acute adverse health effects related to air quality standards. The missing point in these acute epidemiologic studies is how much the observed effects are purely acute or if they also reflect the consequences of a long-term exposure combined with an acute episode of pollution. However, it is difficult to correlate long-term effects, such as gland hypertrophy or carbon deposition, to acute mortality studies. Perhaps our results would provide more support to the epidemiologic decrease in survival reported in the work of Dockery et al in six US cities. In this study, long-term deleterious effects of PM10 levels were observed at lower levels than Guarulhos. We should admit that, although we have statistical significance, at times the mean values are relatively close together with a lot of “spread” in the data. Another problem is that not all occupational exposures are the same. It is possible that the occupational exposures in urban areas with high levels of PM10 differ from the occupational exposures in the more rural areas, and that these exposures could cause the changes noted. canadian neightbor pharmacy

About this blog

Blog invites submissions of review articles, reports on clinical techniques, case reports, conference summaries, and articles of opinion pertinent to the control of pain and anxiety in dentistry.