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Single fish
Lake average
1
10
Pyrenees
Pyrenees
1
0.1
R
2
= 0.8347
R
2
= 0.5046
0.01
0.1
1
10
PCB (ng g
-1
)
100
1
10
PCB (ng g
-1
)
1
1
Tatras
Tatras
0.1
0.1
R
2
= 0.1321
R
2
= 0.0396
0.01
0.01
1
10
100
1
10
100
PCB (ng g
-1
)
PCB (ng g
-1
)
Figure 8.3
Concentrations of various PCBs and PBDEs in fish from high-mountain
Pyrenean and Tatran lakes. (Based on Gallego
et al
. 2007.)
consequence of mainly protein carbon respiration and lack of feeding. Despite the
lack of change in the total amount, the concentration increases from larvae to pupae
are very relevant for the pollutant ingestion of higher predators. The concentration
differences between larvae and pupae are apparently stronger for PBDEs than for
OCs (Fig. 8.6), which suggest a higher retention of the former, consistent with the
higher molecular volume of the brominated compounds. The intakes of OCs and
PBDEs by trout (or any other predator) are between two- and fivefold higher per
calorie gained when feeding on pupae than on larvae (Bartrons
et al
. 2007).
Temperature dependence is also observed for other environmental components,
including lacustrine sediments (Europe: Grimalt
et al
. 2001), snow (Europe:
Carrera
et al
. 2001; Canada: Blais
et al
. 1998), soils (Tenerife Island, Spain: Ribes
et al
. 2002) and mosses (Andes: Grimalt
et al
. 2004). PCBs were found in all snow
samples collected in European sites (Carrera
et al
. 2001). HCHs were also very
abundant, whereas DDTs were found at lower concentrations. Some of the major
compounds found in snow samples, e.g. HCH and PCB, occur predominantly in
the gas phase. Their high abundance in the snowpack reflects the occurrence of
effective transfer mechanisms from gas to snow flakes. A temperature dependence
of the snow concentrations of both volatile and non-volatile OCs is observed.
Thus, higher levels of pollutants are found at lower temperatures. However, these
dependences are more clearly defined for the less volatile compounds.
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