Reaction mass of calcium disilicide and calcium silicide

Repeated dose toxicity: dermal

Administrative data

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Secondary source. Read-across to synthetic amorphous silica.

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1958

Reference 2

Reference Type:

review article or handbook

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

on intact and abraded skin in 0.5 % CMC

GLP compliance:

no

Limit test:

yes

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:

Silicon dioxide

Test animals

Species:

rabbit

Strain:

other: albino

Sex:

male/female

Administration / exposure

Type of coverage:

not specified

Vehicle:

CMC (carboxymethyl cellulose)

Details on exposure:

on intact and abraded skin in 0.5 % CMC

Duration of treatment / exposure:

3 wks

Frequency of treatment:

18 h/d, 5 d/wk

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 5000, 10000 mg/(kg bw*d)
Basis:
nominal per unit body weight

No. of animals per sex per dose:

2

Control animals:

yes, concurrent vehicle

Positive control:

Cosmetic talc (10 g/(kg bw*d)

Examinations

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes

Results and discussion

Effect levels

Dose descriptor:

NOAEL

Effect level:

>= 10 000 mg/kg bw/day (nominal)

Sex:

male/female

Basis for effect level:

other: overall effects clinical signs; mortality; body weight; gross pathology; organ weights; histopathology

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

No evidence of systemic toxicity or of gross or microscopic pathology; no significant difference in dermal irritation between control and dose groups

Applicant's summary and conclusion

Executive summary:

In a repeated dose toxicity study via dermal route (Cabot Inc. 1958, see also ECETOC 2006), pyrogenic Cab-O-Sil fluffy showed no evidence of systemic toxicity or of gross or microscopic pathology, and no significant difference in dermal irritation between control and dose groups.