Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
21 Aug. - 04 Sep. 1990
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP guideline study. Read-across to synthetic amorphous silica.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1990
Report Date:
1990

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
GLP compliance:
yes
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Sident 9, >98% (SiO2), Na20 <1%, Al2O3 <0.2%, SO3 <0.8%,
Fe2O3 <0.03%: CAS-Name: Silica, precipitated, cryst.-free;
CAS-No.: 112926-00-8

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Winkelmann Versuchstierzucht, Borchen/Germany
- Age at study initiation: 9 wks (male), 10 wks (females)
- Weight at study initiation: 183 - 191 g (male), 141 - 152 g (female)
- Fasting period before study: 16 h before start
- Housing: single in Macrolon cages
- Water: ad libitum
- Acclimation period: >= 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.5 - 22.5 °C
- Humidity (%): 40 - 70 %
- Air changes (per hr):
- Photoperiod (hrs dark / hrs light): 12 / 12 hours

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
other: aqueous suspension with 1 % carboxymethyl cellulose
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 237 mg silica/mL suspension
- Amount of vehicle (if gavage): 21.5 ml/kg bw (including 5100 mg TS)
- Justification for choice of vehicle: suspending the test material and stabilising the suspension
- Lot/batch no. (if required):

MAXIMUM DOSE VOLUME APPLIED: 21.5 ml/kg bw


Doses:
5110 mg/kg bw
237 mg/ml
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: days 0, 7, and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight
Statistics:
not relevant

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 5 000 mg/kg bw
Mortality:
none
Clinical signs:
no particular findings
Body weight:
normal weight gain
Gross pathology:
no particular findings

Applicant's summary and conclusion

Interpretation of results:
other: non-toxic
Executive summary:

Jahn et al. (1990) studied the acute oral toxicity of precipitated silica in rats. Five male and five female animals were used. The dose was applied by gavage as aqueous suspension (21.5 ml/kg bw = 237 mg silica/ml suspension). No acute effects were observed, and the LD50 value was >5,000 mg/kg.