TOXICOLOGICAL ASSESSMENT OF AZARCON, A LEAD SALT USED AS A FOLK REMEDY IN MEXICO .1. ORAL TOXICITY IN RATS

Azarcon, a lead tetroxide salt, is used among Mexican and Mexican-Amer ican populations for the treatment of digestive illness. Chemical anal ysis of the azarcon sample used in this study showed it to be 96% lead , 1% calcium, 1% other minor metals, and 2% unidentified material. Tak ing into account the fact that Pb absorption was estimated at 2% follo wing a single oral administration of 100 mg/kg (Aungst et al., 1981), it is possible to propose a chemical interaction between the component s of azarcon, and as a result, the toxicity of Pb tetroxide would be d ifferent when given as azarcon than when given as a pure compound. The present work studied this possibility, with the following results. Wh en the treatments of equal doses of pure Pb tetroxide and azarcon were compared (158 mg/kg/day p.o. for 96 h), five of nine tissues studied had similar Pb concentrations. However, with the pure compound the Pb levels were higher in bone and intestines; while with azarcon the Pb l evels were higher in heart and brain. The pure Pb tetroxide treatment affects lipid peroxidation only in liver, but a low induction of perox idation was found also in kidney and heart in rats which received the azarcon treatment. Liver and kidney damage were evident in rats treate d with a high dose of azarcon (1.1 g/kg/day p.o. for 96 h), while the effects with the pure compound were similar in type but lower in magni tude. Pb tetroxide as a pure compound inhibits ALA-D by 26% while an i nhibition of 42% was found with azarcon. Our results demonstrate that azarcon and lead tetroxide as a pure compound have different toxicolog ical properties.