Reaction mass of calcium disilicide and calcium silicide

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable well-documented study report, comparable to guideline study.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1972

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

no

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Hydrated Calcium Silicate (Silene EF)

IUPAC Name:

Hydrated Calcium Silicate (Silene EF)

Details on test material:

FDA-compound 71-41
Fine white powdered material

Test animals

Species:

mouse

Strain:

CD-1

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: No data
- Age at study initiation: adult
- Weight at study initiation: 28-32 g
- Fasting period before study: no data
- Housing: individually
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): fresh tap water ad libitum
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): controlled temperature
- Humidity (%): controlled humidity
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:

VEHICLE
- Justification for use and choice of vehicle (if other than water): water
- Concentration in vehicle: various
- Amount of vehicle (if gavage): 1 ml/kg bw

Analytical verification of doses or concentrations:

not specified

Details on mating procedure:

- Proof of pregnancy: vaginal plug referred to as day 0 of pregnancy

Duration of treatment / exposure:

day 6 to day 15 of gestation

Frequency of treatment:

daily

No. of animals per sex per dose:

16 mg/kg: 27; 74 mg/kg: 26; 350 mg/kg: 29; 1600 mg/kg: 29 animals

Control animals:

yes, sham-exposed

Details on study design:

- Other: Positive controls treated with 150 mg/kg Aspirin

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: No data

DETAILED CLINICAL OBSERVATIONS: No data

BODY WEIGHT: Yes
- Time schedule for examinations: days 0, 6, 11, 15 and 17 of gestation

FOOD CONSUMPTION AND COMPOUND INTAKE : Yes (observations, no calculations)

POST-MORTEM EXAMINATIONS: No data
- Sacrifice on gestation day 17

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No data
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: No
- Number of late resorptions: Yes
- Other:

Fetal examinations:

- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: 1/3 per litter
- Skeletal examinations: Yes: 2/3 per litter

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Effect levels (maternal animals)

1

Dose descriptor:

NOAEL

Effect level:

1 600 mg/kg bw/day

Basis for effect level:

other: developmental toxicity

2

Dose descriptor:

NOAEL

Effect level:

1 600 mg/kg bw/day

Basis for effect level:

other: maternal toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Effect levels (fetuses)

Remarks on result:

not determinable due to absence of adverse toxic effects

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Maternal exposure of mice to Ca-silicate during days 6-15 of pregnancy did not cause any signs of teratogenicity or maternal toxicity even at the highest dose of 1600 mg/kg bw.

Executive summary:

The teratogenic effects of Ca-silicate were studied in mice (Food and Drug Research Laboratories 1972). Maternal exposure of mice to Ca-silicate during days 6-15 of pregnancy did not cause any signs of teratogenicity or maternal toxicity even at the highest dose of 1600 mg/kg bw.