Use of hydra for chronic toxicity assessment of waters intended for human consumption.

Methods developed with the cnidarian, Hydra attenuata (Pallas), have proven effective for screening acute toxicity in aqueous samples, whereas their use in revealing (sub)chronic toxic effects have had mitigated success. We therefore sought to explore manifestations of hydra mortality and abnormal morphological changes, as well as the reproductive capacity of hydras to further enhance the bioassay sensitivity and to assess (sub)chronic toxicity. These parameters were recorded following the onset of experiments after 8, 12 and 19-21 days of hydra exposure.

Induction of micronuclei and binuclei in blood, gill and liver cells of fishes subchronically exposed to cadmium chloride and copper sulphate.

Common carp (Cyprinus carpio), Prussian carp (Carassius gibelio) and Peppered cory (Corydoras paleatus) were evaluated as target species to perform genotoxicity tests for heavy metals. Fishes were exposed to different doses of cadmium (0.005-0.