Removal of cadmium (Cd) present at low levels (1 µg L-1) in water was investigated using three different microorganism treatments: the microalga Chlorella vulgaris, the fungus Aspergillus niger, and for the first time biopellets composed of C. vulgaris and A. niger. After 5 days, all microorganism treatments resulted in significantly lower Cd concentrations compared with the control. Biopellets treatment resulted in significantly lower pH values than other microorganism treatments, indicating that the biopellets should be investigated further for their water treatment capacity, since pH is a factor affecting the fate of numerous pollutants in water. Use of biopellets as a method to simplify harvesting of microalgae from water is also suggested.
Keywords: biopellets; cadmium; fungi; microalgae; water treatment.