Registration Dossier

Administrative data

Endpoint:
dermal absorption in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2002-04-02 to 2--2-04-29
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2003
Report date:
2003

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 428 (Skin Absorption: In Vitro Method)
Principles of method if other than guideline:
Recommended Protocol for in vitro Percutaneous Absorption Rate Studies (Federal Register, April 3, 1996, Vol 61, No. 65, pp 14773-14778).
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
Dodecamethylcyclohexasiloxane
EC Number:
208-762-8
EC Name:
Dodecamethylcyclohexasiloxane
Cas Number:
540-97-6
Molecular formula:
C12H36O6Si6
IUPAC Name:
dodecamethylcyclohexasiloxane
Radiolabelling:
yes

Test animals

Species:
human
Sex:
male/female

Administration / exposure

Type of coverage:
semiocclusive
Vehicle:
unchanged (no vehicle)
Duration of exposure:
24 h
Doses:
6 mg/cm2
No. of animals per group:
epidermis samples from 6 cadavers; 3 met barrier integrity test

Results and discussion

Total recovery:
After 24-hour semi-occluded contact, 46.4% applied D6 was found on the skin; 40% was volatilized; 3% was found in the skin; virtually none (0.003%) penetrated the skin. Total recovery from all analyzed samples was 89.5%. A further wash at 24 h indicated that D6 present in the skin did not penetrate the skin but continued to evaporate. Under the conditions of this in vitro study D6 did not penetrate human epidermis.

Applicant's summary and conclusion

Conclusions:
A well conducted guideline in vitro study found no penetration by D6 through samples of human skin in 24-hour semi-occluded contact.