Chemistry Reference
In-Depth Information
ACCUMULATED LOAD
170
160
150
140
130
120
110
100
DRY
DRY AND WET
90
80
70
60
50
40
30
20
10
0
Fig. 9 Accumulated load of organochlorine compounds in deposition samples collected between
20 May 1999 and 19 May 2000 at Teide (2,367 m; Tenerife) [
13
]
4 Historical Trends of POP Atmospheric Pollution
in the European Environment
Data on past atmospheric concentrations of POPs is scarce. However, alpine lake
ecosystems can be used as sentinel ecosystems to reconstruct the atmospheric
pollution load over the European continent [
50
,
51
,
65
,
66
].
Alpine lakes essentially receive pollutant inputs from regional or long-range
atmospheric transport [
50
,
51
]. Depending on the physical-chemical properties of
the compound and the climate conditions, the compounds enter these lakes through
gas exchange, dissolved in rain drops, snowflakes or adsorbed/absorbed to aerosols.
Once the POP has entered into the lake system, interactions take place between the
compounds, particles, water and organisms. The strength of the interactions
depends on the water solubility of the individual POPs, or their affinity to organic
material, as well as on the climate conditions, e.g. water temperature [
67
-
71
]. Thus,
POPs with relatively high solubility, like HCHs, mostly occur in the dissolved
