Stannous chloride (SnCl2) is employed as a reducing agent to obtain Technetium-99m-labelled
radiopharmaceuticals in nuclear medicine kits, being inject endovenously in humans. Toxic effects of these kits were not studied, thus making it important to evaluate their impact in humans. The use of natural extracts as medicines is growing around the world. The chayotte (Sechium edule) is a subtropical vegetable with potent diuretic action. It is used in folk medicine due its hypotensor effect. In this study, plasmid deoxyribonucleic acid (DNA) was exposed to chayotte extracts (macerated and decoct) (0.1 g.mL-1 ) in presence of stannous chloride (SnCl2). Samples of the plasmid DNA were analyzed through agarose gel electrophoresis. The results show that the chayotte extracts were capable of damaging the DNA in the presence and in the absent of SnCl2. [Nature and Science. 2004;2(3):48-54].