Four aquatic toxicity studies were conducted using vanadium hydroxide oxi (in the presence of aluminum hydroxide). Using inductively-coupled, plasma- emission spectroscopy (ICP), the vanadium concentrations of test solutions were measured. Since aluminum can be toxic to aquatic species in some circumstances, it should be recognized that the sample tesled also contained aluminum hydroxide. The results are described below based upon mean measured vanadium concentrations. Since aluminum was not measured, it may have played an undefined role in the observed toxicity.