Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Toxicological information

Carcinogenicity

Currently viewing:

Administrative data

Endpoint:
carcinogenicity: oral
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
3 (not reliable)
Rationale for reliability incl. deficiencies:
significant methodological deficiencies
Remarks:
insufficient for a reliable tumor analysis due to low number of animals (biostatistical limitations)
Cross-reference
Reason / purpose for cross-reference:
reference to same study

Data source

Referenceopen allclose all

Reference Type:
other company data
Title:
Unnamed
Year:
1953
Report date:
1953
Reference Type:
study report
Title:
Unnamed
Year:
1956
Report date:
1956

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
other: OECD Guideline 452 (Chronic Toxicity Studies)
Deviations:
yes
Remarks:
Group size 15 m+ 15 f, histopathology with 6 m + 6 f per group, smaller than the recommended 50 (note: Sufficient biostatistical power can never be achieved for substances that have no or a very low cancerogenic potential.)
Principles of method if other than guideline:
see 7.5.1: Columbia 1956_Silene(CS)_oral,24 mon,rat,key,RL2
GLP compliance:
no

Test material

Constituent 1
Reference substance name:
Silicic acid, calcium salt
EC Number:
215-710-8
EC Name:
Silicic acid, calcium salt
Cas Number:
1344-95-2
IUPAC Name:
Silicic acid, Calcium salt
Test material form:
solid

Test animals

Species:
rat
Strain:
other: albino
Sex:
male/female

Administration / exposure

Route of administration:
oral: feed
Vehicle:
other: gelatine (15 g/100 mL water)
Analytical verification of doses or concentrations:
no
Duration of treatment / exposure:
2 years
Frequency of treatment:
daily, continuous
Doses / concentrations
Remarks:
Doses / Concentrations:
1.0, 5.0, 7.5 and 10 % (w/w) in feed
Basis:
nominal in diet
No. of animals per sex per dose:
15
Control animals:
yes, concurrent vehicle

Examinations

Observations and examinations performed and frequency:
see IUCLID section 7.5.1
Sacrifice and pathology:
GROSS PATHOLOGY: Yes

ORGAN WEIGHTS: Yes (see table 51)
liver, kidneys, and spleen (both sexes, each group)

HISTOPATHOLOGY: Yes (see table 50)
Tissues from 6 m and 6 f each dose level and control preserved in formalin:
thyroid, lung, heart, liver, kidney, stomach, large and small intestine, pancreas, spleen,
adrenal, urinary bladder, gonads, bone marrow, and skeletal muscle

Results and discussion

Results of examinations

Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
effects observed, treatment-related
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Food efficiency:
effects observed, treatment-related
Gross pathological findings:
effects observed, treatment-related
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
no effects observed
Details on results:
Result (carcinogenicity): negative; for non-neoplastic and other effects see IUCLID section 7.5.1

Effect levels

Key result
Dose descriptor:
NOEL
Effect level:
ca. 2 500 - <= 3 200 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
not specified
Basis for effect level:
body weight and weight gain
Remarks on result:
other: corresponds to 5 % dietary level

Target system / organ toxicity

Key result
Critical effects observed:
no

Any other information on results incl. tables

No difference in survival from the control, and no gross signs of toxicity; highest dose group: growth suppression; slightly elevated pH of the urine; no tumors are observed. The NOEL is considered to be the 5% dietary level, which is estimated to correspond to about 2500 - 3200 mg/(kg bw*d), based on reduction in body-weight gain and isolated cases of calculi and brittle in kidney and urinary bladder, respectively, as well as a few cases of cholangitis-like lesions at the higher dose levels.

Applicant's summary and conclusion

Conclusions:
no evidence of carcinogenic potential