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Administrative data

Description of key information

There is no acute oral toxicity data available for silver bromide. Read-across is applied to other, comparable silver substances. The acute oral toxicity of silver compounds is low (LD50, oral all >2000 mg/kgbw for AgCl, Ag, Ag2O, Ag2CO3 and Ag2SO4), indicating a generally low systemic toxicity and bioavailability of silver. For the most comparable compounds, AgCl, an LD50 oral of >5110 mg/kg has been determined. It is noted that the solubility of AgBr (140 µg/L) is even lower than for AgCl (1.9 mg/L). Testing for acute oral toxicity for AgBr is thus not considered to be scientifically justified.  Testing for acute inhalation toxicity is also scientifically unjustified for AgBr (see respective justification for waiving). Testing for acute dermal toxicity is scientifically not justified for AgBr, because of the low potential for any dermal penetration (see section on toxicokinetics) and the generally low acute, systemic toxicity.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records
Reference
Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1988-09-27 to 1988-10-17
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study. At the time of the study conduct, GLP was not compulsory. However, the study was conducted in accordance with the principles of GLP.
Qualifier:
according to guideline
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
not specified
GLP compliance:
yes
Test type:
standard acute method
Limit test:
yes
Species:
rat
Strain:
other: BOR: WISW (SPFCpb)
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Uinkelmann Versuchstierzucht GmbH & Co. KG., Borchen
- Age at study initiation: 8 weeks (males) and 9 weeks (females)
- Weight at study initiation: 151 - 161 g (males) and 135 - 155 g (females)
- Fasting period before study: 16 hours before treatment
- Housing: in Macrolon cages, type II, individually housing
- Diet: ad libitum (Standard diet, ssniff R, "Special Diet for Rats")
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 - 22.5
- Humidity (%): 45 - 65
- Photoperiod: 12 hours dark/light cycle
Route of administration:
oral: gavage
Vehicle:
other: Mixture of Witepsol H 15 and Miglyol 812 1 : 1.2 w/w; Miglyol 812 (Mittelkettige Triglyceride DAB 9) and Vitepsol H 15 (Hartfett DAB 9), both supplied by ASTA-Pharma AG, Frankfurt/M. 1
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 237 mg/mL

MAXIMUM DOSE VOLUME APPLIED: 21.5 mL/kg
Doses:
5110 mg/kg body weight
No. of animals per sex per dose:
5 male and 5 female rats
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 or 21 days after administration
- Frequency of observations and weighing:
The animals were continuously observed for the first 4 to 6 hours after administration and then once daily. The nature of the toxicity as well as the onset, the intensity and the duration of the signs were recorded.
Mortality was checked twice daily. Time of death and number of dead animals per dose were documented.
The body weights were recorded at the beginning and also 7 and 14 days after administration. In one male and one female rat the body weights were also determined on day 21.
- Necropsy of survivors performed: yes; at the end of the observation period the animals were sacrificed with C02. A gross necropsy was performed on all animals deceased intercurrently or sacrificed at the end of the observation period. Macroscopic examination included external appearance, body orifices, body cavities (thoracic and abdominal) and their contents.
Statistics:
no data
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 5 110 mg/kg bw
Mortality:
Deaths did not occur.
Clinical signs:
The signs of toxicity were slight to moderate hypokinesia, stilted gait, piloerection, sunken sides, vocalization on handling, red crusted noses, and diarrhea with black discoloured feces. Individual rats additionally showed chromodacryorrhea and strenuous respiration. One male circled his head and forelegs by movement of his hindlegs and one female was not capable of standing on her forelegs but the forepart of her body tilted to the left or right side.
Mostly the symptoms were recorded one hour to five days after administration. Chromodacryorrhea occurred only on day 14 and one female did not recover completely until it was sacrificed on day 21.
Body weight:
All animals showed expected gain in body weight during the study.
Gross pathology:
At necropsy no changes were recorded.
Brain and spinal cord of the female rat that did not recover completely were examined microscopically, but changes could not be detected.
Other findings:
Diarrhea was caused by the vehicle alone, too.
Interpretation of results:
practically nontoxic
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The LD 50 values for silver chloride tested in a single dosewere above 5110 mg/kg for male and female rats (limit test).
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed

Acute toxicity: via inhalation route

Link to relevant study records
Reference
Endpoint:
acute toxicity: inhalation
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
other:
Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Link to relevant study records
Reference
Endpoint:
acute toxicity: dermal
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
other:
Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Justification for selection of acute toxicity – oral endpoint
Read-across to acute oral toxicity studies with other silver substances; LD50 for AgCl >5110 mg/kg; LD50 >2000 mg/kg for Ag, Ag2O, Ag2CO3 and Ag2SO4.

Justification for selection of acute toxicity – inhalation endpoint
Waiving

Justification for selection of acute toxicity – dermal endpoint
Waiving

Justification for classification or non-classification

There is no acute oral toxicity data available for silver bromide. Read-across is applied to other, comparable silver substances. The acute oral toxicity of silver compounds is low (LD50, oral all >2000 mg/kgbw for AgCl, Ag, Ag2O, Ag2CO3 and Ag2SO4), indicating a generally low systemic toxicity and bioavailability of silver. For the most comparable compounds, AgCl, an LD50 oral of >5110 mg/kg has been determined. It is noted that the solubility of AgBr (140 µg/L) is even lower than for AgCl (1.9 mg/L). Testing for acute oral toxicity for AgBr is thus not considered to be scientifically justified. Testing for acute inhalation toxicity is also scientifically unjustified for AgBr (see respective justification for waiving). Testing for acute dermal toxicity is scientifically not justified for AgBr, because of the low potential for any dermal penetration (see section on toxicokinetics) and the generally low acute, systemic toxicity.

In consequence, silver bromide does not require classification for acute toxicity endpoints.