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(225) Toxicity test with Daphnia magna as a backup to Metal Pollution Index. Teodorovic, Ivana1, Djukic, Nada2, Dalmacija, Bozo3, 1 2 3 ABSTRACT- Environmental regulations in Yugoslavia are still focused on single chemical approach and ambient standards. However, new regulations are currently being prepared and there is a chance that biologically based control and monitoring programs along with the whole effluent toxicity testing will finally be included into legislature. One of the methods recently suggested is Fish Metal Pollution Index (Teodorovic et al., Tiscia Monograph Series, 147-154, 2000). It has been proposed as a simple, cost-effective method for metal pollution monitoring of continental waters, as it enables presentation of trace metals fish liver concentration as a single unit-less value and, therefore, evaluation, classification and time trend analysis within the region. Fish MPI - based water quality assessment of the selected sites within the Yugoslav part of the River Danube indicated that metal pollution of section upstream Novi Sad (Vojvodina) could be regarded as a rather serious environmental issue. To evaluate precision and reliability of fish MPI, and, on the other hand, to discriminate between the effects of background pollution and direct contamination from Yugoslav territory, series of WET testing have been undertaken. Daphnia magna acute and sublethal tests combined with chemical analysis identified electroplating factory as a major contributor of metal pollution in the region. Although Ni, Cr and Zn concentration in the studied wastewater do not significantly exceed effluent limits, the effect threshold to D. magna was low. These results correspond with high fish MPI values found near the discharge. During the study period, the plant had undertaken significant efforts concerning wastewater treatment and was certified by ISO 14000. D. magna toxicity tests were sensitive enough to detect the improvement of effluent quality. As bioaccumulation is relatively slow process, the sensitivity of fish MPI regarding the change is still to be assessed. Key words: wet testing, biomonitoring, metal pollution index, Daphnia magna |
