3,4-dihydro-2H-pyran

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

3,4-dihydro-2H-pyran

EC Number:

203-810-4

EC Name:

3,4-dihydro-2H-pyran

Cas Number:

110-87-2

Molecular formula:

C5H8O

IUPAC Name:

3,4-dihydro-2H-pyran

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Study design: in vivo (LLNA)

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

25, 50, and 100%

No. of animals per dose:

5

Details on study design:

The study was performed according to OECD testing guideline 429.

Statistics:

For all statistical calculations SigmaStat for Windows (Version 2.0) was used. A One-Way-Analysis-of-Variance was used as statistical method. In case of significant results of the One-Way-ANOVA, multiple comparisons were performed with the Dunnett test or the Student Newman Keuls test. Statistical significance was set at the five per cent level (p < 0.05). The Dean-Dixon-Test was used for identification of possible outliers (performed with Microsoft Excel 2003).

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: vehicle control: 1.00 25%: 1.37 50%: 1.44 100%: 4.74

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: vehicle control: 650.7 (mean) 25%: 889.1 (mean) 50%: 940.1 (mean) 100%: 3084.1 (mean)

Any other information on results incl. tables

calculation of the EC3:

Test item concentration %	S.I.
50 (c)	1.44 (d)
100 (a)	4.74 (b)
EC3 = (a-c) [(3-d)/(b-d)] + c =73.6%(w/w)

Applicant's summary and conclusion

Interpretation of results:

Category 1B (indication of skin sensitising potential) based on GHS criteria

Conclusions:

The test item 3, 4-Dihydro-2H-pyrane was found to be a skin sensitiser in the Local Lymph Node Assay.

Executive summary:

3,4-Dihydro-2H-pyrane was assessed for its skin sensitising potential using the Local Lymph Node Assay (LLNA) in mice. The test was performed using test item concentrations of 25 and 50% (w/w) in acetone:olive oil (4+1 v/v) and 100% (undiluted test item).

In this study Stimulation Indices (S.I.) of 1.37, 1.44, and 4.74 were determined with the test item at concentrations of 25 and 50%, and 100%, respectively. A dose response was observed. An outlier was not identified in any of the tested groups. The EC3 value calculated was 73.6%. A statistically significant and biologically relevant increase in DPM value, lymph node weight and - cell count was observed in the high dose group (100%) in comparison to the vehicle control group. Furthermore, the cutoff-value for a positive response regarding the lymph node cell count index of 1.55 reported for BALB/c mice was exceeded in the high dose group.