Registration Dossier

Administrative data

Description of key information

Mouse local lymph node assay (read across)

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Referenceopen allclose all

Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
[Please provide information for all of the points below. Indicate if further information is included as attachment to the same record, or elsewhere in the dataset (insert links in 'Cross-reference' table)]

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
[Describe why the read-across can be performed (e.g. common functional group(s), common precursor(s)/breakdown product(s) or common mechanism(s) of action]
The source chemical was chosen based on results from the OECD QSAR Toolbox. The source and target chemicals share common functional groups and have a high degree of structural similarity.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
[Provide here, if relevant, additional information to that included in the Test material section of the source and target records]
See the test material sections of the study records.

3. ANALOGUE APPROACH JUSTIFICATION
[Summarise here based on available experimental data how these results verify that the read-across is justified]
The source chemical was chosen based on results from the OECD QSAR Toolbox. The source and target chemicals share common functional groups and have the highest degree of structural similarity identified for chemicals tested for sensitization (70,80%).

4. DATA MATRIX
The target chemical is not classified for health hazards based on the available measured data (acute oral toxicity, skin irritation, eye irritation, mutagenicity). The source chemical is classified as a Category 2 skin and eye irritant and a respiratory irritant. This read across result is supported by other structurally similar neighbors in the QSAR Toolbox analysis (see attached data matrix).
Reason / purpose:
read-across source
Parameter:
SI
Value:
0.9
Test group / Remarks:
10%
Parameter:
SI
Value:
0.9
Test group / Remarks:
20%
Parameter:
SI
Value:
1.2
Test group / Remarks:
40%
Cellular proliferation data / Observations:
CELLULAR PROLIFERATION DATA
not specified

EC3 CALCULATION
not calculated. All results < 3

CLINICAL OBSERVATIONS:
not specified

BODY WEIGHTS
not specified
Interpretation of results:
GHS criteria not met
Remarks:
Not classified by CLP Criteria
Conclusions:
In a guideline OECD 429 study (in vivo LLNA), ethyl benzoylacetate, a structural analog of Intermediate F37 identified with the aid of the OECD QSAR Toolbox, was not sensitizing.
Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
not specified
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Qualifier:
according to
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Deviations:
not specified
GLP compliance:
not specified
Type of study:
mouse local lymph node assay (LLNA)
Specific details on test material used for the study:
Not specified
Species:
mouse
Strain:
CBA
Sex:
female
Details on test animals and environmental conditions:
- Age at study initiation: 7-12 weeks
Vehicle:
other: acetone
Concentration:
10, 20 or 40 %
No. of animals per dose:
according to OECD 429 test guideline
Details on study design:
Animals were exposed topically on the dorsum of both ears to 25 µL of test material or to an equal volume of the relevant vehicle alone. Treatment was performed daily for 3 consecutive days. Five days after the initiation of exposure, all mice were injected via the tail vein with 250 µL of phosphate-buffered saline containing 20 µCi of tritiated thymidine. The mice were sacrificed 5 hours later, and the draining auricular lymph nodes were excised and pooled for each experimental group or each individual animal. The incorporation of tritiated thymidine measured by beta scintillation counting was reported in disintegrations per minute. An SI was calculated for each chemical-treated group as the ratio of the disintegrations per minute in the treated group (or mean disintegrations per minute when individual animals were assessed) to the disintegrations per minute or mean disintegrations per minute of the concurrent vehicle control group. A substance was classified as a skin sensitizer if, at one or more test concentrations, it induced a threefold or greater increase in local lymph node proliferative activity when compared with concurrent vehicle-treated controls (SI, >= 3).
Positive control substance(s):
not specified
Parameter:
SI
Value:
0.9
Test group / Remarks:
10%
Parameter:
SI
Value:
0.9
Test group / Remarks:
20%
Parameter:
SI
Value:
1.2
Test group / Remarks:
40%
Cellular proliferation data / Observations:
CELLULAR PROLIFERATION DATA
not specified

EC3 CALCULATION
not calculated. All results < 3

CLINICAL OBSERVATIONS:
not specified

BODY WEIGHTS
not specified
Interpretation of results:
GHS criteria not met
Remarks:
Not classified by CLP criteria
Conclusions:
In a guideline OECD 429 study (in vivo LLNA), ethyl benzoylacetate was not sensitizing.
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

In a guideline OECD 429 study (in vivo LLNA), ethyl benzoylacetate, a structural analog of Intermediate F37 identified with the aid of the OECD QSAR Toolbox, was not sensitizing.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

Based on the available data, Intermediate F37 is not classified as a sensitizer according to Regulation (EC) No 1272/2008.