A new macrocyclic ligand 1,1'-bis(bis-(6,6'-oxymethylenyl-2,2'-bipyridine) binaphthyl, (L), and its complexes CuL(ClO4)(2), CuL(NO3)(2,) 3H(2)O, CdL(ClO4)(2), and PbL(ClO4)(2) have been synthesized and characterized on the basis of IR, H-1 NMR, C-13 NMR, FAB mass, and elemental analyses. Genotoxicity of these metal complexes has also been investigated by cytokinesis- blocked micronucleus assay in cultured human lymphocytes. Blood cultures were set up from two healthy donors, and treatment was done with different test concentrations for 24 and 48 h. The current results indicate that all compounds caused cytotoxicity by decreasing the cell number at the 150 mu g/mL doses for 48-h treatments. On the other hand, CuL(ClO4)(2), CuL(NO3)(2,) 3H(2)O and PbL(ClO4)(2) exhibited genotoxicity by inducing the number of micronucleated cells at doses of 150 mu g/mL for 24-h treatments, but CdL(ClO4)(2) did not significantly alter micronucleus induction. Hence, some test compounds may act as mutagens or produce clastogenic effects depending upon their chemical structures.