Analytical chemical considerations on tumor genesis

The differences in the content of both heavy metals and free radicals in tu mors and normal tissue of kidneys have been analyzed. Concentration of free radicals was measured by means of a superoxide dismutase biosensor that ha s been recently developed in our laboratory. Two main differences were obse rved: 1) higher metal concentration in normal tissues than in tumor ones; 2 ) higher concentrations of radicals and toxic agents, as particularly benze ne, in tumor tissue with accompanying lower concentrations of radical scave ngers. Such differences in radical concentrations can be related to: lowere d superoxide dismutase activity in tumor tissue and production of free radi cals by means of so named secondary metabolism pathways of some compounds a dsorbed from the environment.