D10: Impact of Contaminants - Hydromod

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Integrated Water Resource Management for Important Deep European Lakes and their Catchment Areas EUROLAKES D10: Impact of Contaminants FP5_Contract No.: EVK1-CT1999-00004 Version: 4.0 Date: 25/07/01 File: D10-vers.4.0.doc Page 22 of 136 5 BACKGROUND INFORMATION TO MATERIALS WITH A PUTATIVE ENDOCRINE IMPACT Persistent Organic Pollutants — POPs In the technical terminology the name "Persistent Organic Pollutants" (POPs) is used. POPs are synthetical chemicals composed of organic chemical compounds and mixtures. Industrial chemicals like PCBs and pesticides like DDT belong to the POPs. POPs are primary products or also involuntarily by-products of the industry and combustion processes. All POPs are effective in very low concentrations, are extremely persistent and hydrophobic. Due to their affinity for body fat they accumulate themselves in the environment and the food chain up to a very high level with a dramatic concentration increase in the respective organisms to the final consumer [GREENPEACE AUSTRIA, WWF CANADA, WWF US]. The existence of POPs is relatively recent, since the industrial production started after World War II. Today POPs are found almost everywhere - in our food, soil, air and water. Some POPs exceptionally accumulate themselves. The content of POPs in the water of the North Sea growths up to the content in the zooplankton about a 5 million times and up to the fishes and birds body fat a 100 million times enrichment is found [Greenpeace Austria, WWF US]. Both organisations refer that impairments of the development and the physical health of humans, mammals, fishes, birds etc., indicated by POPs, are numerously documented. Particularly in the case of humans an accurate allocation to one cause is not usually possible. Due to the mixture of POPs and the humans individual way of life with other factors of risk are the cause for this situation. Apart from the ingestion, workers and residents of townships near POP-emission sources for example can be exposed by inhalation and skin contact. The persistent pollutants have the ability - when released into the environment - to be transported on air currents or the water to places far away from their point of origin. In a cold climate and at low solar radiation POPs are break down slowly and they scarcely evaporate at very low temperatures. In consequence of that, a particularly strong accumulation in the coldest regions of the earth, e. g. Greenland, Arctic and Antarctica takes place [GREENPEACE AUSTRIA, WWF US]. In Austria, dioxins especially accumulate in barrier effects in the mountains. An increase of the dioxin concentration in soil with increase of the Sea level was ascertained [GREENPEACE AUSTRIA]. Global Spread [LEISEWITZ 1996, WWF CANADA] refer to the ban of some substances (e. g. DDT),which led to a decrease of the concentration in the water and also in organisms. The high remaining base concentration at organochlorine compounds however is based on the further input of substances from residual waste in the respective regions, the remobilization of persistent materials from depots e. g. sediment, its accumulation in organisms themselves and from the long-distance haulage from regions where they are still used. Streams of the oceans, air currents and rivers, which pass the agriculture runoff and industrial discharges into the oceans are important POP transport pathways.
Integrated Water Resource Management for Important Deep European Lakes and their Catchment Areas EUROLAKES D10: Impact of Contaminants FP5_Contract No.: EVK1-CT1999-00004 Version: 4.0 Date: 25/07/01 File: D10-vers.4.0.doc Page 23 of 136 Therefore particularly the aquatic systems of the estuaries, the coastal area and the marginal seas are concerned beside the inland waters. Figure 5-1: Grasshopper effect with consequences to Canada [WWF Canada] Because organochlorine compounds are volatile, they are able to be prevalent by air currents over both hemispheres to places far away from their point of origin. With diminishing temperature they condense at different latitudes and are precipitated. Such a transport can consist of a number of "hops" from one place to another. Each hop consists of three stages: evaporation, transport in the atmosphere and condensation at lower temperatures. Scientists have called this phenomenon the "grasshopper effect". Because evaporation is minimal in colder regions, POPs tend to build up in arctic and mountain ecosystems (cf. 0). Figure 5-1 shows the grasshopper effect at the example of Canada which is impaired by POP-sources resided beyond the state boundary [LEISEWITZ 1996, WWF CANADA]. Detection Problems Environmental chemicals are trace elements which occur only in very low concentrations in the water or in organic material. Their detection is costly. The weak activity of these substances is well balanced by the persistence and accumulation capacity. The detection of material is not the detection of their impact. From the observation of harmful patterns and the simultaneously existence of suspicious substances there does not exist a unequivocal causal connection. For the detection of the impact experiments are necessary. Moreover, today it is not possible to derive or predict the hormonal impact of contaminants from their structure [LEISEWITZ 1996]. He continues that tests of materials are necessary but they give only limited information. The reason therefore is, that the test results normally contain no information about the impacts of the material on
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D10: Impact of Contaminants - Hydromod

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