Exploring options for the assessment of air pollutants effects on human health

CARRERAS, H.A.

Davos, Suiza

Conferencia; International Disaster Reduction Conference; 2006

Epidemiological studies have established that despite the reduction of air pollution to levels close to air quality standards, adverse health effects can still be evidenced, which suggests that no real threshold concentrations exists for some pollutants. Although the evidence is very strong that air pollution causes mortality and morbidity, it is difficult to allocate to a single pollutant. For health impact assessment PM10 is currently the most often reported measure in epidemiological studies. Moreover, it has been reported that a slight increment in particulate mass is related with a significant increase in daily death counts, and that the heavy metals content of these particles are involved in respiratory disorders. However, in many areas of the world systematic monitoring networks are not yet implemented which render very difficult the health impact assessments. These regions require rapid and cost effective evaluation of the deleterious effects of air pollution, mainly in countries experiencing a rapid increase in environmental load as a result of urbanization and industrialization. The objective of the present project was to validate a risk-assessment methodology that connects information obtained from biomonitors and biological markers with some public health outcomes. Cordoba is one of the most polluted cities in Argentine; the emission of pollutants into the atmosphere grew by 50% in the last decades. Although the situation is critical, there are no data on the quantity or quality of air pollutants discharged and all indicators seem to point to a worsening situation. Lichenic species, as well as epiphytes and vascular plants were employed several times as biomonitors in and around the city of Cordoba. On the other hand, epidemiological surveys were employed to estimate the frequency of different health outcomes. It was possible to identify the most important anthropogenic sources located in the study area. Highest heavy metal concentrations were found at sites close to metallurgical and industrial areas. In the city downtown it was observed a prevalence of pollutants released by traffic, while the level of particulate material and some heavy metals were dominated by the emissions of a cement plant which uses 14% of secondary fuels. Epidemiological investigations revealed that the occurrence of asthma has a strong association with the distribution pattern of particulate material and some heavy metals.  The results indicate that biomonitoring networks can be employed as sensitive and early warning indicators of exposure to air pollutants before the occurrence of any human health damage.