Geoscience Reference
In-Depth Information
identifying these risks as being health risks or climate risks [ROU 01a]. This is quite
a difficult question to answer because pollution levels fluctuate in relation to
changes that occur in the climate, yet pollution itself can influence climate change.
Is this a question of increased anthropocentrism or a rediscovery of the importance
of the interface that exists between man and his environment? Air quality is
symbolic of the changes in the nature of the risks that have been observed in modern
society. damages that was once created by natural risks was replaced by pollution
that was created by large factories and industries. Nowadays, disasters and the
threats of destruction are created by humanity itself [DEL 87]. Health risks are only
a small part of the dangers that our modern day society, called “risk society” has had
to deal with
[BEC 03], a society in which it has become necessary to develop
measures to help prevent atmospheric pollution.
Identifying health risks is no longer a question of comparing a pollution value
with an air quality standard. Progress made in the fields of epidemiology and
toxicology means that it is possible to distinguish between short-term and long-term
health risks. An epidemiological study that evaluated the risks of urban pollution on
human health was carried out in the region of Paris between 1987 and 1995 [ERP
94]. This study was regularly updated and the results of this study meant that it was
possible to understand the short-term impacts (a period of several days) that
atmospheric pollution had on human health. These results, in conjunction with
numerous studies carried out in the same field, reinforced the idea that there is a
clear relationship between air pollution and disease. This relationship is referred to
as having no threshold limit, meaning that regardless of what the level of pollution
is in the air, there is always the risk of disease. Pollution is dangerous regardless of
the quantities of pollution that are present in the atmosphere. This observation
questions the importance of certain standards that were set and which suggested that
pollution levels that were under a particular threshold did not have a harmful effect
on human health. Pollution peaks are no longer indicators that can be used to
provide information on health risks. In fact, they are used to indicate the chronic
levels of pollution that need to be monitored. The majority of these standards, which
are prepared by the CAFE
10
, refer to average annual values that indicate the
existence of background pollution that needs to be monitored.
6.3.3.2.
The mapping and spatialization of health risks
The use of GIS means that it is possible to work out the location of people who
are exposed to any given level of pollutants in the air. GIS can be used to calculate
how much pollution certain members of the population have been exposed to. This
calculation is worked out by crossing two pieces of information: first of all by using
pollution levels plotted on a map, and second, by using the total number of
inhabitants who are resident in the area, which corresponds to a colored area on the
10
Clean Air For Europe.
