glyoxal … %; ethandial … %

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1987

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

(1981)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Test was performed before the LLNA guideline was available.

Test material

Test material information

Constituent 1

Reference substance name:

Glyoxal

EC Number:

203-474-9

EC Name:

Glyoxal

Cas Number:

107-22-2

Molecular formula:

C2H2O2

IUPAC Name:

oxalaldehyde

Test material form:

liquid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Tank 409

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: cooling
- Stability under test conditions: stability has been demonstrated by analysis when stored at ca. 8 °C

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Lippische Versuchstierzucht, Hagemann GmbH & Co. KG, Extertal, Germany
- Weight range at study initiation: 250-309 g
- Housing: 5 animals per cage, Makrolon cage type IV
- Diet: 341.4 mm (Kaninchen-Meerschweinchen-Haltungsdiät), FA. Klingentalmuehle AG, CH-4303 Kaiseraugst, Switzerland, ad libitum
- Water: Tap water ad libitum, supplemented twice a week with about 2 g of ascorbic acid per 10 litres of water
- Acclimation period: at least 7 days prior test initiation

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Air changes (per hr): housing in fully air-conditioned rooms
- Photoperiod (hrs dark / hrs light): 12 h/ 12 h

REMARK:
- The feed used in the study was assayed for contaminants. In view of the aim and duration of the study the contaminants occuring in commercial feed did not influence the results.
- The drinking water is regularly assayed for contaminants by the municipal authorities of Frankenthal and the Technical Services of BASF SE. In view of the aim and duration of the study there were no special requirements exceeding the specifications of the drinking water.

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

water

Induction 2

Concentration / amount:

- The concentrations used for testing were selected on the basis of the results of a pretest;
- For the first induction, the test substance was used as 20% solution in either distilled water or Freund´s adjuvant/water (1:1);
- For the second induction, the test substance was used as such, i.e. unchanged;
- For both challenges, the test substance was used as 10% solution in distilled water;
- All test solutions were prepared immediately prior treatment, using an Ultraturrax or a magnetic stirrer for mixing.

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

water

Challenge 2

Concentration / amount:

- The concentrations used for testing were selected on the basis of the results of a pretest;
- For the first induction, the test substance was used as 20% solution in either distilled water or Freund´s adjuvant/water (1:1);
- For the second induction, the test substance was used as such, i.e. unchanged;
- For both challenges, the test substance was used as 10% solution in distilled water;
- All test solutions were prepared immediately prior treatment, using an Ultraturrax or a magnetic stirrer for mixing.

No. of animals per dose:

10 animals per control group (2 groups)
20 animals per test group

Details on study design:

- The test method was based on Magnusson and Kligman (J. Invest. Dermatol. 52, 268-276, 1969)
- A test group of 20 and two control groups of respectively 10 Pirbright White, Dunkin, Hartley guinea pigs were used for the adjuvant test procedure; the test concentrations were selected upon the results of a preliminary test.
- The first induction was intradermal, and the test substance was used as 20% solution in distilled water, resp. in Freund´s adjuvant/water (1:1).- The second induction was percutaneous occlusive and the test substance was applied unchanged.
- The two challenges were percutaneous occlusive, and the test substance was used as 10% solution in distilled water; skin readings were performed after 24, 38 and 72 hours following each challenge.
- As recommended by Annex VI/II D of the Council Directive of July 29, 1983 for the 5th Amendment of the Directive 67/548 EEC (= 83/467 EEC), the results were considered to be positive when at least 30% of the experimental animals exhibit skin reactions; furthermore, only the findings obtained 48 hours after application were taken into account for the determination of the sensitization rate.
- Negative controls: the control animals were used to rule out a substance-induced primary skin irritation.

Positive control substance(s):

yes

Remarks:

dinitrochlorobenzene (DNCB) was tested twice a year as positive control substance on the selected guinea pig strain in the testing laboratory.

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

48

Group:

negative control

Dose level:

10% TS in aqua dest.

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

Control group 1: after both challenges, no positive skin reaction was seen. Control group 2: This control group only was considered for rechallenge; no positive skin reaction was seen.

Results 2

Key result

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10% TS in aqua dest.

No. with + reactions:

7

Total no. in group:

19

Clinical observations:

One animal in the test group died 7 days after intradermal induction. After the first challenge and at reading time point 48 h, 7/19 animals showed positive skin reactions, consisting mostly of distinct erythema.

Results 3

Key result

Reading:

rechallenge

Hours after challenge:

48

Group:

test chemical

Dose level:

10% TS in aqua dest.

No. with + reactions:

11

Total no. in group:

19

Clinical observations:

After the second challenge, 11/19 animals were scored positive (slight to distinct erythema).

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria