Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 434-430-9 | CAS number: -
An assessment of the contact hypersensitivity to EA-3098 was assessed by a LLNA study.
The Stimulation index values calculated for the substance concentrations 1, 10 and 25% were 1.3, 1.0 and 0.9 respectively.
If results indicate a SI ≥3 the test substance may be regarded as a sensitiser. Therefore, the test substance is not considered to be a skin sensitiser based on the LLNA study.
Preliminary irritation study:
The results of the epidermal exposures for the selection of the highest test substance concentration to be tested in the main study are described in Table 1 (attached background material).
Based on the results, the highest test substance concentration selected for the main study was a 25% concentration.
Induction phase (Table 2 - attached background material):
The skin effects seen after the third epidermal exposure are presented in Table 2. No irritation was observed in any of the animals examined.
Macroscopy of the nodes and surrounding area (Table 2 - attached background material):
All nodes of the experimental and control groups were considered normal in size. No macroscopic abnormalities of the surrounding area were noted.
Body weights (Table2 - attached background material):
Body weights and body weight gain of experimental animals remained in the same range as controls over the study period. The slight body weight loss, noted in some animals, was considered not toxicologically significant.
Toxicity and Mortality:
No mortality occurred and no symptoms of systemic toxicity were observed in the animals of the main study.
Calculation of stimulation index (SI)
1% test substance
10% test substance
24% test substance
Acetone/Olive oil (4:1 v/v)
Assessment of the contact hypersensitivity to EA-3098 in a LLNA study was assessed using the following guidelines:
- OECD No. 429 (2002)
- EC Council Directive 67/548/EEC, Annex V, B.42 (2004)
- EPA, OPPTS 870.2600 (2003) "Skin Sensitisation"
Test substance concentrations selected for the main study were based on the results of a preliminary study.
In the main study, three groups of five experimental animals were epidermally exposed to test substance concentrations of 1%, 10% or 25% on three consecutive days. Five vehicle control animals were similarly treated, but with vehicle alone (acetone/olive oil (4:1 v/v)). Three days after the last exposure, all animals were injected with 3H-methyl thymidine and after five hours the draining (auricular) lymph nodes were excised. After precipitating the DNA of the lymph node cells, radioactivity measurements were performed. The activity was expressed as the number of Disintegrations Per Minute (DPM) and a simulation index calculated for each group.
No irritation was observed in any of the animals examined.
Mean DPM/animal values for the experimental groups with test substance concentrations 1, 10 and 25% were 261, 207 and 170 respectively. The mean DPM/animal value for the vehicle control group was 199.
The SI values calculated for the substance concentrations 1, 10 and 25% were 1.3, 1.0 and 0.9 respectively.
There was no indication that the test substance could elicit an SI >3. It was established that the EC3 value (if any) exceeds 25%.
The six month reliability check with hexylcinnamic aldehyde indicates that the LLNA as performed is an appropriate method for testing contact hypersensitivity.
Based on these results EA-3098 is considered to be a non-sensitiser.
Local Lymph Node Assay
The LLNA study on the test substance was negative and this study is considered valid for the assessment of the substance.
Justification for selection of skin sensitisation endpoint:
The study has been conducted according to OECD Guideline 429 and GLP and is adequately reported. The study has been assigned a reliability 1.
Migrated from Short description of key information:
No data available. However, as inhalation is not expected to be a significant route of exposure and aerosols of the substance are not anticipated to be respirable, sensitisation of the respiratory system is not considered to be of concern, also taking into account the negative result for sensitization in the LLNA study.
Skin sensitisation (Local Lymph Node Assay):
If results indicate a SI ≥3 the test substance may be regarded as a sensitiser. Therefore, based on the results of the LLNA study, the test substance does not meet the criteria for a positive result for skin sensitisation and therefore does not meet the criteria for classification as a skin sensitiser.
The conducted LLNA study on the substance is considered valid for assessment of the substance and for classification purposes.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Close Do not show this message again