Docosan-1-ol

Dermal absorption

Administrative data

Endpoint:

dermal absorption in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP

Data source

Reference

Reference Type:

publication

Title:

Percutaneous absorption of aliphatic compounds.

Author:

Iwata Y, Moriya Y, Kobayashi T

Year:

1987

Bibliographic source:

Cosmet. Toiletries 102(2): 53-68.

Materials and methods

Principles of method if other than guideline:

¹⁴C labelled test substances were applied to the dorsal skin using a plaster for a 24 hour period. Immediately following application each animal was placed in a container to measure expiratory excretion. At the end of the exposure period the treated area of skin was excised and dissolved using tissue  solubiliser. The carcass was homogenised in a blender with sodium hydroxide. An aliquot of the homogenate was then dried and combusted for determination of radioactivity. The effect of different solvents and concentration of the solvent was also investigated. The role of skin irritation in absorption of test substance was examined.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Hexadecan-1-ol

EC Number:

253-149-0

EC Name:

Hexadecan-1-ol

Cas Number:

36653-82-4

Molecular formula:

C16H34O

IUPAC Name:

hexadecan-1-ol

Test material form:

other: Liquid

Radiolabelling:

yes

Test animals

Species:

mouse

Strain:

other: HR/De

Sex:

not specified

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Remarks:

also tested in three solvent vehicles: TEC, castor oil and squalane.

Duration of exposure:

24 hours

Doses:

Up to 100% concentration in three vehicles and undiluted

No. of animals per group:

3

Control animals:

no

Results and discussion

Percutaneous absorption

Key result

Dose:

100%

Parameter:

percentage

Absorption:

ca. 1 %

Remarks on result:

other: 24 hours

Any other information on results incl. tables

The percentage absorbance of dose ¹⁴C-cetyl alcohol (octdecan-1-ol) = ca 1%. At least 65% of the absorbed dose is excreted as carbon dioxide in the expired air.

When tested diluted in solvent vehicles, the degree of absorption was influenced by the concentration and the type of solvent that was used.

For n-cetyl alcohol in squalene, approximately 2% of the applied dose was absorbed at the 0.5%, reducing with increased concentration to 1% of the applied dose at 5%.

For n-cetyl alcohol in castor oil and in TEC (triethyl citrate), slightly less was absorbed at the applied concentrations of 0.5 and 5%

Applicant's summary and conclusion

Conclusions:

Of a dose of 1-14C-cetyl alcohol (5%) in squalene applied to the skin of nude mice for 24 hours under occlusive conditions, 1 % was absorbed.

Executive summary:

Of a dose of 5% 1-14C-cetyl alcohol applied to the skin of nude mice for 24 hours under occlusive conditions, 1% was absorbed.