Sodium bromide

Long-term toxicity to fish

Description of key information

Key study: Test method according the Dutch Standarization Organization Guidelines (1980). The NOEC was determined to be 0.0078 g Br-/litre (0.01 g NaBr/L).
Key study: Test method according the Dutch Standarization Organization Guidelines (1980). The NOEC was reported to be 0.25 g/L (0.32 g NaBr/L).
Key study: Test method equivalent or similar to OECD Guideline 215 (Fish, Juvenile Growth Test). After 1 month of exposure, the NOEC value, based on histopathological changes, was determined to be 10 mg/L, whereas the NOEC after 3 months' exposure was determined to be 32 mg/L, based on behaviour, appearance and histopathological changes.
Key study: Test method equivalent or similar to OECD Guideline 210 (Fish, Early-Life Stage Toxicity Test). The LC0 (No lethal concentraion) was 5600 and 3200 mg/L in fish exposed up to 3 weeks and 3 months, respectively. 
Supporting study: No guideline was followed. No analytical monitoring was made. The NOEC based on behaviour in Poecilia reticulata was determined to be 32 mg/L.
Supporting study: No guideline was followed. No analytical monitoring was made. The NOEC in Oryzias latipes, based on behaviour, was determined to be 320 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

10 mg/L

Additional information

Key study: A reproductive toxicity test with sodium bromide on Poecilia reticulata was performed in accordance with the Dutch Standarization Organization Guidelines. The test organisms were exposed for 124 days to 0, 7.8. 78, 390, 780, 3900 and 7800 mg Br-/litre. The LC50 was determined to be > 7.8 g Br^-/litre (10 g NaBr/L), whereas the EC50, based on mortality and behaviour was determined to be 0.17 g Br^-/litre (0.22 g NaBr/L) and the EC50 based on reproduction was 0.14 g Br^-/litre (0.18 g NaBr/L). The NOEC based on mortality and behaviour was determined to be 0.078 g Br^-/litre (0.1 g NaBr/L) and, based on reproduction, the NOEC was determined to be 0.0078 g Br^-/litre (0.01 g NaBr/L). The histopathological examination showed three major pathological lesions: thyroid hyperplasia (in the groups exposed to ≥ 78 mg Br^-/L), regressive changes in the female reproductive tract (at ≥ 390 mg Br^-/L) and myopathy in high incidence in the 3900 and 7800 mg Br-/L groups.

Key study: A long-term toxicity test with sodium bromide on Oryzias latipes was performed in accordance with the Dutch Standarization Organization Guidelines. O. latipes eggs were exposed for 34 days to different concentrations of the test substance. The LC50 was determined to be 1.5 g Br^-/litre (1.93 g NaBr/L), whereas the EC50, based on mortality and behaviour was determined to be 0.37 g Br^-/litre (0.47 g NaBr/L). The NOEC based on mortality and behaviour was found to be 0.25 g Br^-/litre (0.32 g NaBr/L); the NOEC based on growth rate was 0.78 g Br^-/litre (1 g NaBr/L); the NOEC based on heart rate and hatching was determined to be ≥ 7.8 g Br^-/litre (10 g NaBr/L). No histologically effects were found in exposed animals.

Key study: In the present study, young Poecilia reticulata fishes were exposed to sodium bromide concentrations ranging from 10 to 32000 mg/l for 1 and 3 months, following a method equivalent or similar to OECD Guideline 215. A NaBr concentration of 100 mg/L and higher caused paresis and paralysis. Histopathology of these animals, exposed to concentrations of 3200 mg/L, showed muscle changes indicative of a functional neuromuscular disturbance. In the thyroid, the epithelium appeared to be stimulated (at 32 and 100 mg/L and higher after 1 and 3 months' exposure, respectively). The development of gonads in both sexes was more advanced than in the controls after the 3 -month exposure period, and there was inflammation in and around the larger blood vessels in the abdomen at concentrations of 3200 mg/L and higher after 3 months. The LC0 (No lethal concentration) was 10000 mg/L and 1000 mg/L after 1 and 3 months, respectively. After 1 month of exposure, the NOEC value, based on histopathological changes, was determined to be 10 mg/L, whereas the NOEC after 3 months' exposure was determined to be 32 mg/L, based on behaviour, appearance, histopathology and thyroid activation.

Key study: In the present study, Oryzias latipes organisms were exposed to sodium bromide concentrations ranging from 180 to 5600 mg/L for 1 and 3 months, following a method equivalent or similar to OECD Guideline 210. Besides monitoring general toxicological parameters, histopathology was performed on total body sections. The NOEC value based on behaviour was determined to be 320 mg/L after 1 and 3 months of exposure. Histopathological changes were found only in the thyroid. Signs of increased activity were observed in the thyroid follicles of all exposed fish: the LOEC value for thyroid activation was determined to be 180 mg/L. The LC0 (No lethal concentration) was 5600 and 3200 mg/L in fish exposed up to 3 weeks and 3 months, respectively.

Supporting study: Poecilia reticulata organisms were exposed to different sodium bromide concentrations in a 28 day semi-static test. 3 -4 week old organisms were maintained in a circadian photoperiod at 23 ± 2 ºC. They were observed for mortality, behaviour and growth. The NOEC based on behaviour was determined to be 32 mg/L and the NOEC based on growth alterations was reported to be 320 mg/L. The LC0 (No lethal concentration) was stated to be at 100 mg/L.

Supporting study: An egg-larval test on Oryzias latipes was performed with sodium bromide. O. latipes organisms were exposed to different concentrations of the test substance in a 40 day semi-static test. They were observed for mortality, growth, behaviour and hatching. The NOEC based on behaviour was determined to be 320 mg/L and the NOEC based on hatching growth was reported to be 10000 mg/L. The LC0 (No lethal concentration) was stated to be at 3200 mg/L.