Docosanoic acid

Direct observations: clinical cases, poisoning incidents and other

Administrative data

Endpoint:

direct observations: clinical cases, poisoning incidents and other

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented study report which meets basic scientific principles

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Study type:

study with volunteers

Endpoint addressed:

skin irritation / corrosion

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Closed epicutaneous test, where 20 substances were investigated for skin irritation in 20 healthy volunteers

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Palmitic acid

EC Number:

200-312-9

EC Name:

Palmitic acid

Cas Number:

57-10-3

Molecular formula:

C16H32O2

IUPAC Name:

palmitic acid

Details on test material:

- Name of test material (as cited in study report): Edenor C16 92/94 (Fettsäure C16) - FS008
- Analytical purity: no data

Method

Type of population:

general

Subjects:

- Number of subjects exposed: 20
- Sex: 12 females, 8 males
- Age: 21 - 50 years
- Other: healthy volunteers

Route of exposure:

dermal

Reason of exposure:

intentional

Exposure assessment:

not specified

Details on exposure:

10µl of the substance at concentration of 50% was applied to the back of the volunteers for 24 hours using a Large Finn Chamber on Scanpor (Herma).

Examinations:

READINGS
The readings of reaction were performed 1, 6, 24, 48, 72, and 144 hours after removal of the chambers.

SCORING
Erythema:
0 - no erythema
1 - very slight erythema (barely perceptible)
2 - well-defined erythema (diameter: 12 mm)
3 - moderate to severe erythema
4 - severe erythema (beet redness) to slight eschar formation (injuries in deep)
 
Edema:
0 - no edema
1- very slight edema (barely perceptible)
2 - slight edema (edges of area well defined by definite raising)
3 - moderate edema (raised appr. 1 mm)
4 - severe edema (raised >1 mm and extending beyond area of exposure)
 
Scaling:
0 - no scaling
1 – dryness
2 – fine scaling
3 – moderate scaling
4 - severe scaling
 
Fissures:
0 - no fissures
1 – very superficial epidermal separation
2 – single or few fissures
3 – deep fissures with bleeding and exsudation

Results and discussion

Clinical signs:

The test substance did not induce erythema, edema or scaling. The scores for erythema and edema were 0 and 0 % of the values induced by the control Texapon N 25, respectivly.

Results of examinations:

SKIN IRRITATION
All readings of the subjects were used for calculation (Sum / Mean+/-SEM).
- Erythema: 0 / 0
- Edema: 0 / 0
- Scaling: 0 / 0
- Fissures: 0 / 0

Outcome of incidence:

The test substance did not induce erythema, edema and scaling.

Applicant's summary and conclusion

Conclusions:

The test substance did not induce erythema, edema and scaling. Thus, it is considered, that palmitic acid possess a good to very good skin compatibility.