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In the coming years the construction of four motorways is planned in Poland: two motorways running east—west (A-2 and A-4) and two running north—south (A-1 and A-3). In spite of their obvious advantages, motorways have adverse environmental impact too. Busy traffic and higher speeds of motor vehicles result in adverse effects to the environment, bringing about contamination with exhaust gases; there is an extensive spread of toxic agents and also noise emissions. The author discusses pollution of air with toxic fractions of exhaust gases. He also deals with lead contamination of cultivars in orchards along motorways and of tree leaves in roadside compact tree belts.
The report by UN special mission sent to Yugoslavia by the Secretary General states: „Destruction of oil refineries, fuel tanks, chemical plants, including fertiliser factories, toxic fumes emitted due to huge fires, leakages of dangerous chemicals into the soil and surface water resulted in (...) environmental contamination to the extent which has not occurred before”. The author focuses on these effects of NATO intervention which are usually omitted, providing numerous examples of environmental contamination.
The following species of sedentary birds with widespread and common occurrence are the most convenient as bioindicators: Magpie Pica pica, Feral Pigeon Columba livia f. domestica, House Sparrow Passer domesticus or Tree Sparrow Passer montanus, Blackbird Turdus merula, Goshawk Accipiter gentilis (feathers) and nestlings of various species. The non-destructive method of feather analysis is suitable mainly for assessment of Pb, Cd, As, Sb, Ge, Tl, and Hg. It cannot be applied for Mn, Ni, Sr, Rb, Mo and Fe that are cumulated in feathers at similar levels in polluted and unpolluted areas. Hg, Zn, Cu, Cr, As and Se have stronger affinity to keratin than others. The method requires strict standardisation, particularly in the way samples are to be collected and prepared for mineralisation. None of feather cleaning procedures removes all contaminants from vane surfaces. With respect to many elements, analysing "concentration in feathers" is a measurement of external deposition therefore metal levels found in feathers correspond more strongly to the data on immission than to the element pool available in food. Mercury is an exception here. In cases of toxic elements as Pb, Cd or Tl it is possible to predict their concentrations in internal tissues on the basis of feather analysis.
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