To evaluate precision and reliability of recently introduced Metal Pollution Index as a method for metal pollution monitoring of surface waters, a series of toxicity tests with Daphnia magna have been undertaken. The sampling sites (the River Danube wetlands and Hydrosystem DTD (Danube - Tisza - Danube), Serbia, Yugoslavia) for this study have been chosen according to previously recorded high MPI values. Chemical characterization and WET (whole effluent toxicity) testing of selected waste waters at the chosen sampling sites, and the recipient water toxicity testing upstream and downstream the discharger evaluated the validity of MPI, and, on the other hand, discriminated the effects of background pollution. The results of acute and chronic toxicity tests of water and sediment corresponded well with MPI values, which leads to a conclusion that MPI could be regarded as a reliable and precise method for metal pollution monitoring of surface waters.

The experiment was performed on marine Teleost Serranus scriba with lower concentrations of lindane then MPC (due to our valid law). The aim of this study was to find the effects of lindane to fish activities connected with nutrition. This motive is among the strongest. It includes parameters as: number of fish movements in the presence of prey or without it and the number of onslaughts to the prey during one hour. The results have shown that the increasing of lindane concentration caused considerable decreasing and even complete cessation of activity. Interest for prey and decreasing activity of predators in the presence of prey (typical for Serranus - as a fish of prey and the hunter) endures till the moment of convulsion.

Sea urchin gametes, embryos and larvae can be used for quick, cheap and reliable screening and testing of pharmacologically active substances and pollutants. Effects of fecal pollution of Kotor Bay water and mercury in sediments and water of Risan Bay on embryonic development of spotted sea urchin (S. granularis), were examined. The results showed malformations, blockade of adhesion blastomeras and normal embryonic development. This distortion of development is about the suppression of the normal process of cortical granule exocytosis during activation reaction that starts fertilization, response Ring wave and increased level of free calcium ions in intimately membrane layer.

TesToks, version 1.0 is the specialized software developed for the toxicity tests data analysis. The paper presents, in short, the options and the constrains of the software.

Pilot screening of sediment quality on selected stretches of HS DTD and transboundary water bodies in Vojvodina Province (Serbia and Montenegro) was set as an objective of this paper. The results of sediment toxicity tests indicated the necessity for remedial activities of the following stretches: DTD Vrbas - Bezdan - sampling site Vrbas - Canal Banatska Palanka - Novi Becej - sampling site Kajtasovo and Begej - sampling sites Klek and Stajicevo.