Semichronic toxicity study of sodium bromide in rats

Abstract

A 90-day toxicity study was carried out in rats on diets containing 0, 75, 300, 1200, 4800 and 19200 ppm sodium bromide. The animals on the highest level did not groom themselves sufficiently and exhibited signs of motor incoordination. The male animals in this group showed significant growth retardation. Plasma bromide levels increased within 3 weeks to a plateau. In all groups, except in the highest dosage group, these plateaus were directly proportional to the bromide concentrations in the diets, as were the bromide concentrations in brain and kidneys after 13 weeks. Total molar halogen concentration in plasma, however, remained constant throughout the investigation. No striking effects on hematological and biochemical parameters were seen except for a doubling of the percentage of neutrophil granulocytes in the highest dosage group. In female animals on 1200, 4800 and 19200 ppm and in male animals on 19200 ppm bromide an increase of relative thyroid weight was found. In male rats an increase of the relative weight of the adrenals was found in the 19200 ppm group and a decrease of relative prostate weight was seen in the two highest dosage groups. Histopathologically a dose-related disturbance of the endocrine system and some of its target organs was found.