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 3 BACKGROUND FP5_Contract No.: EVK1-CT1999-00004 Version: 4.0 Date: 25/07/01 File: D10-vers.4.0.doc Page 8 of 136 3.1 THE UNDERLYING PROBLEM In [LEISEWITZ 1996] it is mentioned that the consumption and the use of synthetic substances – which cannot be found in the nature - have an enormous influence on the ecological balance. These xenobiotics are usually persistent and there impact may be felt on the whole globe caused by world-wide use and/or atmospheric long-distant transport. In addition, they are already effective in relatively small dosages. Their accumulation in organisms, the food chain, the soil, waters and sediments (from where they can be mobilised) have the consequence of a long-term effect even at a very low input. Furthermore they are not recoverable from the biosphere. Most of these contaminants are dissolved in water. Via rivers and the atmosphere they enter the oceans. Therefore particularly the aquatic systems of the estuaries, the coastal area and the marginal seas have to be concerned besides the inland waters. [LEISEWITZ 1996] continued that through predator-prey-relationships these substances can be transmitted also. Thus, their concentration in the organism increases rapidly (biomagnification). Even children and their parents are connected with each other through the food chain. The application of man-made substances can be effected over the blood supply of a growing embryo, over the suckle or substances being included in the egg. Such a passing on of one generation to the next, causes an accumulation in the organisms of the affected individuals and have a negative influence on the offspring's early stages of development, especially on organs and control mechanisms developing in a fast and intensive metabolic process at the growing germ, the embryo and baby. This metabolic process where genetic and the hormone system work together is part of a complicated control mechanism being still unknown in many respects. If it comes to a disorder, development disturbances, deformations, erroneous trends and the dying of the germ could be the consequences. In the past the main attention to check health damages caused by environmental chemicals was a possible toxic, carcinogenic or teratogenic effect. Since the 1990s the hormone effect of contaminants is known. The hormonal regulation is decisive for the tissue differentiation /proliferation of the crotch and the spermatogenesis. This regulation will be deranged by hormone-like substances or substances which are able to disturb the balance of the hormone system. This means the same substances operate also reproduction-damaging as endocrine disrupters [LEISEWITZ 1996]. On the basis of today’s incomplete knowledge final statements about the effects of pesticide residues on the human health respectively on the water ecology can not be made. The risk lies in the complex effect of small dosages of different active substances and not on the toxicity of a single substance. On the one hand pollutants reach waters directly via sewage treatment plants and on the other hand diffusely. The input of pesticides into the ground water depends on the application practice, soil conditions as well as the mobility and degradability of the substance. The use of herbicides on railroad installations is a problem if the substances trickle away directly through the track ballast without passing an active soil layer where they at least partly be metabolised [BUWALa].
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 9 of 136 Today, nearly 100,000 synthetic chemical substances are in use. If they are hardly biodegradable these substances flow with the sewage in water basins. Most of the chronic environmental disturbances were not predictable and are recognised only with the first damages. Several laws and regulations control the use of such problematic substances to protect the waters [BUWALa]. Because the chemical structure of every substance is different, it has different properties and must be assessed individually. Therefore, the large and constantly growing number of substances causes a huge amount of work for the licensing authorities. In the environmental impact assessment of a substance the important factors are - in addition to its properties - the way in which it is used and disposed and the consumed quantity. A priority is given in Germany to the 2,000 substances which are produced in quantities of over 1,000 t/a ("high production volume chemicals") [BUWAL b]. For a preventive health protection, however, it would be necessary to avoid such substances being suspected having hormonal effects. 3.2 CURRENT HANDLING OF THE EDC PROBLEM IN THE EUROPEAN UNION In December 1999 the Communication on a "Community Strategy for Endocrine Disrupters, a range of substances suspected of interfering with the hormone systems of humans and wildlife" COM (1999) 706 final was published by the European Commission. The objectives of this paper are two-fold. On the one hand the identification of the endocrine disrupting problem, its causes and consequences, on the other hand the identification of appropriate policy action an the basis of the precautionary principle in order to respond quickly and effectively to the problem, thereby alleviating public concern. Four key elements are identified on the basis of which an appropriate set of actions is recommended. These are: the need for further research, the need for international co-ordination, the need for communication to the public and the need for policy action. With regard to the need for further research it is said in the paper COM (1999) 706 final, that for substances suspected to be endocrine disrupters a list is to be compiled. To identify the selection criteria used to place substances on this list further scientific data collection and research is necessary. In addition, it is necessary to assess the quantities of these substances in the environment, based on an examination of the material flow of each substance. This includes production volumes, consumption in further processing and final products and import/export volumes. It is essential to carry out further research in these areas and to investigate the need for refinement of current risk assessment methodologies to address endocrine disrupters. Because, while no agreed test methods and no effective screening and testing strategy are available the communication continues, many substances, for which little information is currently available, may escape attention when compiling a list of potential ED substances.In order to support a rapid development of test methods, the EU may consider necessary to implement a research effort into the mechanisms of action of the endocrine system and the range of effects, including the role of hormones at key stages of life circles. In addition, further investigations are required into the links between adverse health effects in humans and wildlife and exposure to specific substances or mixtures of substances. Here are included the health consequences of phytoestrogens and hormones used as growth promoters.
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D10: Impact of Contaminants - Hydromod

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