metal concentrations are always lower in the Rhône River and higher in the Seine
River, i.e. inversely to their suspended solid loads, the per capita loads of the Seine
River are the greatest for Hg and Cd, the highest per capita Zn fluxes are observed in
the Garonne River, while the lowest fluxes of all metals are in the Loire River. The
top ranking of the Seine for Cd, although well-known mine tailings have also
contaminated the Garonne for decades [79], is due to the numerous plating workshops and industries in Paris in the 1960s until the 1980s. The particular pattern of
Pb in the Rhone River suggests a shift in reference values. In this highly impounded
basin whose solid discharge was considerably reduced during the last century, it is
possible that a catchment with a high Pb background has become a higher contributor to the Pb background in the last few decades.
These per capita figures for French rivers are compared to those of other industrial
countries, at the peak contamination, i.e. the pre-regulation stage (Table 2C). They
present a remarkable similarity.
8 Trajectories of the Environmental Issues Affecting River
Basins and Society: Example of PCB Contamination
in the Seine River Basin
The trajectory of the water quality situation (Fig. 1) includes the following components [74]: (1) the evolution of a state indicator measured during the targeted period;
(2) the relevant pressure or driver indicator; (3) the first awareness of a deterioration
of water quality, its social recognition, environmental monitoring and assessment
and reporting; and (4) the technical and/or regulatory responses provided. Here, the
trajectory is completed by a brief analysis of how scientific knowledge of this issue
has evolved, in particular its controlling factors. For micropollutants, the state
indicator might not always be derived from the regulatory survey (see Sect. 3) but
from the sedimentary archives. Historical archives are used to reconstruct other
components of trajectories: the scientific knowledge of the inhabitants’ perception
of the problem and the interactions between key actors, including controversies. This
approach is therefore typically interdisciplinary. It has been tested in the Seine River
basin for trace metals and requires a large amount of information to complete these
components and the circulation of the contaminant within the anthroposphere, as for
metals [36].
Figure 12 is an attempt to describe the trajectory of PCBs in the Seine River basin.
The state indicator is the total PCB content in the dated core profile from [15], taken
at the river outlet (65,000 km
2 ).
PCBs are one of the first industrial products to be regulated and then banned.
Following the alert made by Rachel Carson (Silent Spring, 1962), PCBs and other
organochlorines such as DDT and lindane were an early concern of some French
scientists [80]. In 1972 these compounds were included on the blacklist of
UNESCO’s International Oceanographic Commission and, in turn, on the list of
Sedimentary Archives Reveal the Concealed History of Micropollutant. . .
293
River, i.e. inversely to their suspended solid loads, the per capita loads of the Seine
River are the greatest for Hg and Cd, the highest per capita Zn fluxes are observed in
the Garonne River, while the lowest fluxes of all metals are in the Loire River. The
top ranking of the Seine for Cd, although well-known mine tailings have also
contaminated the Garonne for decades [79], is due to the numerous plating workshops and industries in Paris in the 1960s until the 1980s. The particular pattern of
Pb in the Rhone River suggests a shift in reference values. In this highly impounded
basin whose solid discharge was considerably reduced during the last century, it is
possible that a catchment with a high Pb background has become a higher contributor to the Pb background in the last few decades.
These per capita figures for French rivers are compared to those of other industrial
countries, at the peak contamination, i.e. the pre-regulation stage (Table 2C). They
present a remarkable similarity.
8 Trajectories of the Environmental Issues Affecting River
Basins and Society: Example of PCB Contamination
in the Seine River Basin
The trajectory of the water quality situation (Fig. 1) includes the following components [74]: (1) the evolution of a state indicator measured during the targeted period;
(2) the relevant pressure or driver indicator; (3) the first awareness of a deterioration
of water quality, its social recognition, environmental monitoring and assessment
and reporting; and (4) the technical and/or regulatory responses provided. Here, the
trajectory is completed by a brief analysis of how scientific knowledge of this issue
has evolved, in particular its controlling factors. For micropollutants, the state
indicator might not always be derived from the regulatory survey (see Sect. 3) but
from the sedimentary archives. Historical archives are used to reconstruct other
components of trajectories: the scientific knowledge of the inhabitants’ perception
of the problem and the interactions between key actors, including controversies. This
approach is therefore typically interdisciplinary. It has been tested in the Seine River
basin for trace metals and requires a large amount of information to complete these
components and the circulation of the contaminant within the anthroposphere, as for
metals [36].
Figure 12 is an attempt to describe the trajectory of PCBs in the Seine River basin.
The state indicator is the total PCB content in the dated core profile from [15], taken
at the river outlet (65,000 km
2 ).
PCBs are one of the first industrial products to be regulated and then banned.
Following the alert made by Rachel Carson (Silent Spring, 1962), PCBs and other
organochlorines such as DDT and lindane were an early concern of some French
scientists [80]. In 1972 these compounds were included on the blacklist of
UNESCO’s International Oceanographic Commission and, in turn, on the list of
Sedimentary Archives Reveal the Concealed History of Micropollutant. . .
293