Fumes, silica

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics in vivo

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: Basic data given, comparable to guideline studies. Read-across to synthetic amorphous silica.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1969

Report date:

1969

Materials and methods

Objective of study:

distribution

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Si analysis: Ammonium-molybdate method according to Stegemann H and Fitzek FJ (1956): Die mikroanalytische Bestimmung von Silizium in quarz- und silikathaltigen Staubproben. Aus der deutschen Forschung der letzten Dezennien. Thieme Verlag Stuttgart 1956

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Silicon dioxide

EC Number:

231-545-4

EC Name:

Silicon dioxide

Cas Number:

7631-86-9

Molecular formula:

O2Si

IUPAC Name:

dioxosilane

Constituent 2

Reference substance name:

Reference substance 001

Details on test material:

HDK V15: >99,8 % SiO2, 150 m2/g (BET), CAS-Name: Silica,
amorphous, fumed, cryst.-free; CAS-No.: 112945-52-5

Surface (BET): 150 +-20 m2/g

Radiolabelling:

no

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

no datails given

Duration and frequency of treatment / exposure:

1 months, 20 applications

Doses / concentrations

Remarks:

Doses / Concentrations:
100 mg/rat = approx. 500 mg/(kg bw*d)

No. of animals per sex per dose / concentration:

20 females

Control animals:

yes, concurrent vehicle

Results and discussion

Toxicokinetic / pharmacokinetic studies

Toxicokinetic parameters

Toxicokinetic parameters 1

Test no.:

#1

Toxicokinetic parameters:

C(time): Si content liver 4.2 µg (control 1.8 µg) after 20 applications (1x/d)

Toxicokinetic parameters 2

Test no.:

#1

Toxicokinetic parameters:

C(time): Si content spleen 5.5 µg (control 7.2 µg) after 20 applications (1x/d)

Toxicokinetic parameters 3

Test no.:

#1

Toxicokinetic parameters:

C(time): Si content kidney 14.2 µg (control 7.8 µg) after 20 applications (1x/d)

Any other information on results incl. tables

SUMMARY (oral)
In 20 rats receiving 20 daily oral doses of 100 mg HDK V15 per animal (about 500 mg/kg bw) each, tissue values (SiO2) apparently were very slightly increased in liver and kidney: in liver 4.2 µg (control value 1.8 µg), in the spleen 5.5 µg (7.2 µg) and in the kidneys 14.2 µg (7.8 µg).

(Note: unclear if results were normalised with reference to organ weights, i.e. per g weight or per total organ.)

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): no bioaccumulation potential based on study results

Executive summary:

In 20 rats receiving 20 daily oral doses of 100 mg silicon dioxide (HDK V15) per animal (about 500 mg/kg bw) each, tissue values (SiO2) apparently were very slightly increased in liver and kidney: in liver 4.2 µg (control value 1.8 µg), in the spleen 5.5 µg (7.2 µg) and in the kidneys 14.2 µg (7.8µg) (Klosterkötter 1969). Based on the report it is unclear if results were normalised with reference to organ weights, i.e. per g weight or per total organ.