THE METAL-METAL INTERACTIONS IN BIOLOGICAL-SYSTEMS .3. DAPHNIA-MAGNA

The toxicity of single metal ions: Al, Co(II), Cr(III), Cu(II), Fe(III ), Mg, Mn(II), Mo(VI), Ni(II), Se(VI), V(V) and Zn and the following p airs of them: Al-Co, Al-Mg, Al-Mo, Al-Se, Al-Zn, Cr-Co, Cr-Mg, Cr-Mo, Cr-Se, Cr-Zn, Cu-Co, Cu-Mg, Cu-Mo, Cu-Se, Cu-Zn, Fe-Co, Fe-Mg, Fe-Mo, Fe-Se, Fe-Zn, Mn-Co, Mn-Mg, Mn-Mo, Mn-Se, Mn-Zn, Ni-Co, Ni-Mg, Ni-Mo, Ni-Se, Ni-Zn, V-Co, V-Mg, V-Mo, V-Se, V-Zn, Zn-Co, Zn-Mg, Zn-Mo, and Z n-Se on Daphnia magna was examined. The most prominent antagonism in t he toxicity was observed in the following ion pairs: Al-Mo(VI), Cr(III )-Co(II), Cr(III)-Mg, Cr(III)-Mo(VI), Cr(III)-Se(VI), Cr(III)-Zn, Fe(I II)-Se(VI), Mn(II)-Mg, Mn(II-Se(VI), Zn-Mg and Zn-Mo(VI). The strong s ynergism was found for the following ion systems: Cr(III)-Se(VI), Cr(I II>-Zn, Fe(III)-Se(VI), Mn(II)-Zn, Mn(II)-Se(VI), Ni(II)-Co(II), Ni(II )-Mo(VI), Ni(II)-Se(VI), Ni(II)-Zn, V(V)-Co(II), V(V)-Mo(VI), V(V)- Se (VI), and V(V)-Zn. Synergism and antagonism in toxicity were dependent on water hardness as well as on the ion concentration. Adaptive proce sess of the animals to the toxic environment could also be observed. T hus, the toxicity of the single ions and their pairs was not linear wi th respect to time.