Observations with Thalassiosira rotula (Meunier) on the toxicity and accumulation of cadmium and nickel.

Cadmium and nickel toxicity thresholds based on generation time, maximum cell density, and chain length as toxicity indicators were evaluated from batch cultures of the marine diatom Thalassiosira rotula in nutrient-enriched seawater as substrate. Nickel toxicity is about an order of magnitude or more higher than cadmium toxicity. The toxicity thresholds decrease with increasing illumination and are not significantly affected by 10 mumol/liter EDTA. From the metal accumulation determined by voltammetry average maximum uptakes of 90 micrograms Ni/g DW and 600 micrograms Cd/g DW were determined.