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Toxicological information

Skin irritation / corrosion

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Administrative data

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
25. March 1992 to
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

Test guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
The patches were applied once weekly to intakt and abraded skin for a 7 day wear interval for 3 weeks to a group of 6 rabbits (3/sex/group) followed by a four week observation period. At the end of a 7 day period the patches were removed and the skin scored for irritation 1h, 24h, 48h, 72h and 7 days after removal. Blood samples were taken 0h, 4h, 8h, 24h, 32h, 48h and 72h during first week of dosing for analysis of estradiol.
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): 3M estradiol TDD containing 1.567 mg estradiol
- Lot/batch No.: FN 5800A

Test animals

Species:
rabbit
Strain:
New Zealand White

Test system

Type of coverage:
occlusive
Preparation of test site:
other: abraded and intakt
Vehicle:
other: patch
Controls:
yes
Duration of treatment / exposure:
7 day wear interval for 3 weeks
Observation period:
3 weeks treatment period plus 4 weeks observation period (7 weeks incl.)
Number of animals:
3/sex/group

Results and discussion

In vivo

Results
Irritation parameter:
overall irritation score
Basis:
mean
Score:
> 0 - <= 1.5
Reversibility:
fully reversible

Any other information on results incl. tables

The estradiol and placebo patches were slightly irritating. The irritation was generally resolved within 48 h. The irritation of 3M Estradiol TDD was slightly higher than of Estraderm TTS patch. The difference in irritation was attributed to greated adhession and resulting continous occlusion of the test site by 3M Estradiol TDD as opposed to the poor adhesion of the Estraderm TTS. Analysis of serum estradiol levels indicated the delivery of active compound in both the test substance and the positive control system.

Applicant's summary and conclusion

Conclusions:
Irritation was rather due to adhesion of patches than of test substance estradiol
Executive summary:

In a 28 day irritation study rabbits were treated with 3M estradiol TDD patch containing 1.57 mg estradiol . The patches were applied to abraded and intact skin once weekly for a 7 day wear interval for 3 weeks to a group of 6 rabbits (3/sex/group) followed by a four week observation period. After removal the skin was evaluated for irritaion at 1h, 24h, 48h, 72h and 7 days after removal. Blood samples were taken 0h, 4h, 8h, 24h, 32h, 48h and 72h during first week of dosing for analysis of estradiol.

No apparent difference between abraded and intact skin or between placebo and estradiol containing patch could be observed. Slight and reversible irritation was provoked by the 3M estradiol TDD patch. Irritation was rather due to adhesion of patches than of test substance estradiol. Classification of estradiol is not required.