Developmental Toxicity of Sodium Chlorite in the Rabbit

Abstract

Chloride dioxide (ClO2) is currently used in many countries as a drinking water disinfectant. Chlorite ion (ClO2-) is the primary degradation product of ClO2 when it is used to treat drinking water. In this study, mated female New Zealand white rabbits received either 0, 200, 600, or 1,200 ppm NaClO2 in their drinking water from Day 7 to Day 19 of pregnancy, inclusive, and were necropsied on Day 28 of pregnancy. Weight of the gravid uterus, number of corpora lutea, implantation sites, and live fetuses were recorded. Live fetuses were weighed, sexed, and examined for external, visceral, and skeletal abnormalities. Maternal food and water consumption were decreased at 600 and 1,200 ppm, however, no treatment-related maternal abnormalities were observed at necropsy. As expected in the presence of maternal effects, mean fetal weights were slightly lower at 600 and 1,200 ppm, with a slightly higher incidence of incomplete ossification of some bones. There were no treatment-related fetal structural abnormalities. Pre- and postimplantation losses were within expected ranges and other reproductive parameters were similar in all groups. At 200 ppm, there were no maternal or fetal effects. NaClO2 was not considered to be teratogenic or a selective developmental toxicant.