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Toxicological information

Developmental toxicity / teratogenicity

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Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1996
Reliability:
2 (reliable with restrictions)

Data source

Reference
Reference Type:
publication
Title:
Prenatal Exposure to Sodium Bromide Affects the Postnatal Growth and Brain Development
Author:
Disse M., Joó F., Schulz H. and Wolff J.R.
Year:
1996
Bibliographic source:
J. Brain Res., 37, 1, 127-134.

Materials and methods

Test guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
Method: other

GLP compliance:
no

Test material

Constituent 1
Reference substance name:
Sodium bromide
EC Number:
231-599-9
EC Name:
Sodium bromide
Cas Number:
7647-15-6
IUPAC Name:
sodium bromide
Details on test material:
Sodium bromide

Test animals

Species:
rat
Strain:
Sprague-Dawley
Details on test animals or test system and environmental conditions:
no further details

Administration / exposure

Route of administration:
oral: drinking water
Vehicle:
water
Details on exposure:
18 rats were dosed with NaBr
14 rats were given tap water
4 rats were given NaCl solution
250 mg% in drinking water
Drinking water supplied ad libitum
Analytical verification of doses or concentrations:
no
Details on analytical verification of doses or concentrations:
no further details
Duration of treatment / exposure:
days 5 to 15 post mating

Frequency of treatment:
Daily

Duration of test:
90 days
Doses / concentrations
Remarks:
Doses / Concentrations:
250 mg% in drinking water
Basis:
nominal in water
No. of animals per sex per dose:
250 mg% in drinking water (250 mg NaBr / 100 mL water)
Control animals:
yes, concurrent no treatment
Details on study design:
Sex: female
Duration of test: 100 days

Results and discussion

Results: maternal animals

Effect levels (maternal animals)

Basis for effect level:
other: effect type not specified

Results (fetuses)

Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:no effects

Fetal abnormalities

Abnormalities:
not specified

Overall developmental toxicity

Developmental effects observed:
not specified

Any other information on results incl. tables

Bromide levels measured in the blood of dams and blood and brain homogenates of pups prior to and immediately after birth were higher than controls but dropped to control levels by PD 19. Compared to controls, a smaller body weight was observed in all bromide-treated rats from birth onwards. Similarly brain weights were consistently smaller in the bromide treated group than in controls remaining about 10% lower than normal brain weight in adults from PD 8. The protein content was also consistently lower in brains of bromide treated rats than in controls from birth onwards. Differences were still apparent at PD 90.

Applicant's summary and conclusion

Conclusions:
Bromide levels measured in the blood of dams and blood and brain homogenates of pups prior to and immediately after birth were higher than controls but dropped to control levels by PD 19. Compared to controls, a smaller body weight was observed in all bromide-treated rats from birth onwards. Similarly brain weights were consistently smaller in the bromide treated group than in controls remaining about 10% lower than normal brain weight in adults from PD 8. The protein content was also consistently lower in brains of bromide treated rats than in controls from birth onwards. Differences were still apparent at PD 90.
Bromide was shown to have little or no effect on development during PD 1 – 10. During PD 10-40 the differences between the treated and control brain weight and protein content peaked and the fell significantly. From PD 40 onwards, deficits in body and brain weights and brain protein content asymptotically reached maximal values.
18 female rats were treated with the test material between days 5 and 15 of gestation and tap water thereafter. A further 18 dams were treated with either tap water or saline solution over the same time period. Postnatal growth was followed by measuring the body weights of the pups. Blood and whole brain homogenates were obtained from pups sacrificed on various days throughout the course of the study until postnatal day 90. Bromide levels in the blood and brain were determined along with body weight, brain weight and brain protein content.
Executive summary:

18 female rats were treated with the test material between days 5 and 15 of gestation and tap water thereafter. A further 18 dams were treated with either tap water or saline solution over the same time period. Postnatal growth was followed by measuring the body weights of the pups. Blood and whole brain homogenates were obtained from pups sacrificed on various days throughout the course of the study until postnatal day 90. Bromide levels in the blood and brain were determined along with body weight, brain weight and brain protein content.

Bromide levels measured in the blood of dams and blood and brain homogenates of pups prior to and immediately after birth were higher than controls but dropped to control levels by PD 19. Compared to controls, a smaller body weight was observed in all bromide-treated rats from birth onwards. Similarly brain weights were consistently smaller in the bromide treated group than in controls remaining about 10% lower than normal brain weight in adults from PD 8. The protein content was also consistently lower in brains of bromide treated rats than in controls from birth onwards. Differences were still apparent at PD 90.

Bromide was shown to have little or no effect on development during PD 1 – 10. During PD 10-40 the differences between the treated and control brain weight and protein content peaked and the fell significantly. From PD 40 onwards, deficits in body and brain weights and brain protein content asymptotically reached maximal values.