tocixity, contact bioassay, sewage sludge, Eisenia foetida, Sinapis alba

The goal of the submitted work was to determine the applicabilityof the combination ot two contact bioassay for assessment of sewage sludge ecotoxicity.The results of the acute toxicity test on Eisenia foetida showed that the with increasing concentration of the sludge sample the mortality of earthworms increases. The value of LC 50 is 385 g of the sewage sludge. The acute toxicity test on Sinapis alba showed the relationship between increasing concentration of the sewage sludge sample and inhibition of the root growth and seeds germinative capacity. The value of 72IC50 was 22.8 g of the sludge. The evaluated sewage sludge can be considered to be potentially ecotoxic.