SUBCHRONIC TOXICITY OF SODIUM-CHLORITE IN THE RAT

Chlorine dioxide (ClO2) is currently used in many countries as a drink ing water disinfectant. The chlorite ion (ClO2-) is the primary degrad ation product of ClO2 when it is used to treat drinking water. In this study, sodium chlorite was administered daily by gavage to rats for 1 3 weeks at dose levels of 0, 10, 25, or 80 mg/kg/day. At the conclusio n of the study, all surviving animals were killed and subjected to a g ross necropsy. Hematology, blood chemistry evaluations and urinalysis were performed. At 80 mg/kg/day, there were several treatment-related deaths and morphological changes in erythrocytes were observed. Mean e rythrocyte count was decreased in both sexes. In males, hematocrit and hemoglobin levels were decreased and methemoglobin levels were increa sed. Splenic extramedullary hemopoiesis was observed in some animals a t 80 mg/kg/day. At 25 mg/kg/day, methemoglobin was increased in males. No adverse toxicological effects were noted at 10 mg/kg/day.