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Toxicological information

Skin sensitisation

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Administrative data

Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Remarks:
Well documented publication, acceptable for assessment with restrictions (limited information on material and methods, no derivation of an EC3 possible based on available data, corrosive substance). Due to the corrosive properties of the substance, all experimental data on skin sensitization are of restricted reliability, since local irritating effects can interfere with effects caused by skin sensitization.

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
The Local Lymph Node Assay: Results of a Final Inter-Laboratory Validation under Field Conditions.
Author:
Scholes EW et al.
Year:
1992
Bibliographic source:
J. Appl. Toxicol. 12: 217-222
Reference Type:
publication
Title:
Comparison of the Local Lymph Node Assay with the Guinea-Pig Maximization Test for the Detection of a Range of Contact Allergens.
Author:
Basketter DA & Scholes EW
Year:
1992
Bibliographic source:
Fd. Chem. Toxic. 30 (1): 65
Reference Type:
review article or handbook
Title:
Structure Activity Relationships in Skin Sensitization using the Murine Local Lymph Node Assay.
Author:
Ashby J et al.
Year:
1995
Bibliographic source:
Toxicology 103: 177-194

Materials and methods

Principles of method if other than guideline:
The study was conducted according to the method described by Kimber et al. (1989, 1991) and Basketter et al. (1991) with one modification. In the study described here animals received topical applications of test chemical on three consecutive days and the assay was terminated after 5 days.
GLP compliance:
not specified
Type of study:
mouse local lymph node assay (LLNA)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
- Name of test material (as cited in study report): 2-Hydroxyethyl acrylate
- Analytical purity: >= 98 % (purity refers to majority of used test chemicals, no specifics given)
- Source: Fluka

In vivo test system

Test animals

Species:
mouse
Strain:
CBA/Ca
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Strain: CBA/Ca
- Source: Barriered Animal Breeding Unit, Alderley Park (laboratory B); Harlan Olac Ltd., Bicester, Oxon (laboratory A, C, D)
- Age at study initiation: approx. 8-12 weeks

ENVIRONMENTAL CONDITIONS
- no details

Study design: in vivo (LLNA)

Vehicle:
other: acetone:olive oil, 4:1 v/v and dimethylformamide (DMF)
Concentration:
5, 10, 25, and 50 %
No. of animals per dose:
4
Details on study design:
MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Criteria used to consider a positive response:
The proliferative activity of lymph node cells (LNC) was expressed as the number of radioactive disintegrations per minute (dpm) per lymph node for each experimental group. The ratio of 3HTdR incorporation by LNC of test lymph nodes relative to that recorded for control lymph nodes test/control (T/C) ratio was calculated for each test group. A test chemical was regarded as positive in the LLNA, if the following criteria were fulfilled:
1. Exposure to at least one concentration of the chemical resulted in an incorporation of 3HTdR at least threefold greater than that recorded in control mice.
2. The data were not incompatible with a conventional biological dose response.

TREATMENT PREPARATION AND ADMINISTRATION:
Groups of mice (n=4) received 25 µL of one of three concentrations of the test chemical on the dorsum of both ears daily for three consecutive days. Control mice received an equal volume of the relevant vehicle alone.
Five days after the initiation of exposure, all mice were injected intravenously via the tail vein with 250 µL of phosphate-buffered saline (PBS) containing 20 µCi of [3H]methyl thymidine (3HTdR: specific activity 2 Ci/mmol, Amersham International, Amersham, UK). Five hours later the mice were sacrificed and the draining (auricular) lymph nodes were excised and pooled for each experimental group. Single-cell suspensions of lymph node-cells (LNC) were prepared by gentle mechanical disaggregation through stainless steel gauze (200 mesh size). The pooled LNC were pelleted by centrifigation at 190 g for 10 min, washed twice with 10 mL of PBS and resuspended in 3 mL of 5 % trichloroacetic acid (TCA). Following overnight incubation at 4 °C, the precipitates were recovered by centrifugation, resuspended in 1 mL of TCA and transferred to 10 mL of scintillation fluid (Optiphase MP, LKB). 3HTdR incorporation was measured by beta-scintillation counting.

Results and discussion

In vivo (LLNA)

Results
Key result
Parameter:
SI
Remarks on result:
other: T/C ratio: 8.2 - 18.1

Any other information on results incl. tables

LLNA results obtained at the collaborating laboratories for the inter-laboratory trial:

 

Conc. [%]

T/C ratio

 

Lab. A

Lab. B

Lab. C

Lab. D

5

-

10.7

-

-

10

9.0

14.8

13.8

12.8

25

8.2

18.1

11.0

8.6

50

toxic

-

11.7

9.9

Vehicle used by Lab.: A, B, D: acetone : olive oil; C: DMF

T/C ratios equal or greater than 3.0 indicate a positive LLNA result. 2 -Hydroxyethyl acrylate elicited positive LLNA responses in all four contributing laboratories.

The available data do not show a clear dose-response relationship. Thus, derivation of an EC3 value and quantification of the substance's sensitizing potency was not possible.

Due to the corrosive properties of the substance, all experimental data on skin sensitization are of restricted reliability, since local irritating effects can interfere with effects caused by skin sensitization.

Applicant's summary and conclusion

Interpretation of results:
Category 1 (skin sensitising) based on GHS criteria