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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:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1979

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Deviations:
yes
Remarks:
Occlusive dressing; 24h exposure; 48h scoring is missing.
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
According to Guideline.

Test system

Type of coverage:
occlusive
Preparation of test site:
other: abraded and shaved
Vehicle:
unchanged (no vehicle)
Controls:
not required
Amount / concentration applied:
0.5 mL
Duration of treatment / exposure:
24 h
Observation period:
7 days
Number of animals:
3

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 24+48+72 h
Score:
1.9
Max. score:
4
Reversibility:
not fully reversible within: 7 days
Remarks on result:
other: Only non-abraded skin - 48 h scoring is extrapolated.
Irritation parameter:
edema score
Basis:
mean
Time point:
other: 24+48+72 h
Score:
1.2
Max. score:
4
Reversibility:
not fully reversible within: 7 days
Remarks on result:
other: Only non-abraded skin - 48 h scoring is extrapolated.

Applicant's summary and conclusion

Interpretation of results:
other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No. 1272/2008.
Conclusions:
Under the condition of this test classification is not justified.
Executive summary:

The classification of TLGR 79.133 is based on a very rigorous treatment of the animals with the test material. Exposure to the test material for 24-hours under occlusive conditions is significantly higher than under the current OECD 404 prescribed exposure of 4-hours under semi-occluded conditions. Higher exposures will likely result in more severe effects. Hence, the results from this study over predict the irritation potential when assessed against new OECD 404 guidance criteria.       

Additionally, the observation period in the previous studies is mostly restricted to 7 days (in contrast to the 14 day prescribed by the current guideline); which does not allow a full appreciation of the reversibility of the observed effects.

 

For one test substance from Shell it could be shown that different protocols result in contrasting results regarding the skin irritancy of the material (TLGR.0157.78 vs. SBGR.93.008; Cas-# 68131-39-5). When tested under current guidelines the material did not met the criteria for Skin irrit., cat. 2, H315.

 

Conclusions: As shown, just by changing the testing conditions to semi-occlusion and a shorter time period; test results for the same substance show a totally different picture. It can also be demonstrated by extending the observation period that the highest irritant responses are reversible. Hence, by weight of evidence and considering the testing conditions under both protocols Skin irrit., cat. 2, H315 is not justified.