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Toxicological information

Skin sensitisation

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Administrative data

Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Data from Peer reviewed publication

Data source

Reference
Reference Type:
publication
Title:
ICCVAM Test Method Evaluation Report. The Reduced Murine Local Lymph Node Assay: An Alternative Test Method Using Fewer Animals to Assess the Allergic Contact Dermatitis Potential of Chemicals and Products
Author:
NIH
Year:
2009
Bibliographic source:
NIH Publication No. 09-6439. National Institutes of Health

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Principles of method if other than guideline:
The protocol for the reduced LLNA is identical to that of the traditional LLNA with one exception. In the traditional LLNA, three dose levels of each test substance are tested, while in the rLLNA only the highest dose level that does not induce systemic toxicity and/or excessive skin irritation is tested for skin sensitizing activity. The term “limit dose”, sometimes used to refer to the rLLNA, accurately depicts a modified LLNA that tests only the highest dose level that does not induce local irritation and/or systemic toxicity. The terms “cut-down” and “reduced” LLNA also accurately describe the reduction in the number of doses tested and emphasize the reduction in the number of animals used to perform the test.
The rLLNA measures lymphocyte proliferation after topical exposure to a potential skin sensitizing substance. The test substance is administered topically on three consecutive days to the ears of mice at a concentration that provides maximum solubility of the test substance without systemic toxicity and/or excessive local irritation. Two days after the final application of the test substance, 3H-thymidine or [125]I-iododeoxyuridine (in phosphate-buffered saline; 250 uL/mouse) is administered via the tail vein. Five hours later the draining auricular lymph nodes are excised, and a single-cell suspension from the lymph nodes of each animal is prepared for quantifying the incorporation of radioactivity, which correlates with lymph node cell proliferation. The incorporation of radioactive 3H-thymidine or [125]I-iododeoxyuridine for each mouse is expressed in disintegrations per minute (dpm). The SI is calculated as the ratio of the mean dpm/mouse for each treatment group against the mean dpm/mouse for the vehicle control group. The threshold for a positive response is an SI of >= 3.
GLP compliance:
not specified
Type of study:
mouse local lymphnode assay (LLNA)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: liquid
Details on test material:
not further specified

In vivo test system

Test animals

Species:
mouse
Strain:
not specified
Sex:
not specified
Details on test animals and environmental conditions:
not further specified

Study design: in vivo (LLNA)

Vehicle:
acetone/olive oil (4:1 v/v)
Concentration:
0.5, 5 and 50%
No. of animals per dose:
no data
Details on study design:
The protocol for the reduced LLNA is identical to that of the traditional LLNA with one exception. In the traditional LLNA, three dose levels of each test substance are tested, while in the rLLNA only the highest dose level that does not induce systemic toxicity and/or excessive skin irritation is tested for skin sensitizing activity. The term “limit dose”, sometimes used to refer to the rLLNA, accurately depicts a modified LLNA that tests only the highest dose level that does not induce local irritation and/or systemic toxicity. The terms “cut-down” and “reduced” LLNA also accurately describe the reduction in the number of doses tested and emphasize the reduction in the number of animals used to perform the test.
The rLLNA measures lymphocyte proliferation after topical exposure to a potential skin sensitizing substance. The test substance is administered topically on three consecutive days to the ears of mice at a concentration that provides maximum solubility of the test substance without systemic toxicity and/or excessive local irritation. Two days after the final application of the test substance, 3H-thymidine or [125]I-iododeoxyuridine (in phosphate-buffered saline; 250 uL/mouse) is administered via the tail vein. Five hours later the draining auricular lymph nodes are excised, and a single-cell suspension from the lymph nodes of each animal is prepared for quantifying the incorporation of radioactivity, which correlates with lymph node cell proliferation. The incorporation of radioactive 3H-thymidine or [125]I-iododeoxyuridine for each mouse is expressed in disintegrations per minute (dpm). The SI is calculated as the ratio of the mean dpm/mouse for each treatment group against the mean dpm/mouse for the vehicle control group. The threshold for a positive response is an SI of >= 3.
Positive control substance(s):
not specified
Statistics:
Yes

Results and discussion

In vivo (LLNA)

Resultsopen allclose all
Parameter:
SI
Remarks on result:
other: The calculated stimulation indices were given with 0.64, 0.69 and 1.71
Parameter:
other: disintegrations per minute (DPM)
Remarks on result:
other: no details reported

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Remarks:
Migrated information
Conclusions:
Dimethyl carbonate was tested in a reduced LLNA (the protocol for the rLLNA is identical to that of the traditional LLNA with one exception, as only the highest dose level that does not induce systemic toxicity and/or excessive skin irritation is tested for skin sensitizing activity), where concentrations of 0.5, 5 and 50% have been tested. The calculated stimulation indices were given with 0.64, 0.69 and 1.71, i.e. the substance gave no indications for a skin sensitizing potential.
Executive summary:

Dimethyl carbonate was tested in a reduced LLNA (the protocol for the rLLNA is identical to that of the traditional LLNA with one exception, as only the highest dose level that does not induce systemic toxicity and/or excessive skin irritation is tested for skin sensitizing activity), where concentrations of 0.5, 5 and 50% have been tested. The calculated stimulation indices were given with 0.64, 0.69 and 1.71, i.e. the substance gave no indications for a skin sensitizing potential.