1,4-dioxane

Endpoint summary

Description of key information

In a well-performed maximisation test using guinea pigs, according to EEC Guideline B6, 1,4-dioxane did not show skin sensitising properties.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

The study was conducted in 1993 when the LLNA was not available as an established method.

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Lippische Versuchsstierzucht, Hagemann GmbH&Co.
- Weight at study initiation: 293-345 gram
- Housing: 5 per cage
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light):12/12

Route:

intradermal and epicutaneous

Vehicle:

water

Concentration / amount:

intradermal induction: 5%
epicutaneous induction: 100%

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

100 %

No. of animals per dose:

control group (0.9% aqueous NaCl-solution): 5 animals
test group: 10 animals

Positive control substance(s):

yes

Remarks:

1-chlor-2,4-dinitro-benzol

Positive control results:

The results showed that the test system was able to detect skin sensitizers.

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

100%

No. with + reactions:

0

Total no. in group:

10

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0%

No. with + reactions:

0

Total no. in group:

5

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

1%

No. with + reactions:

20

Total no. in group:

20

Upon intradermal induction well-defined signs of erythema and oedema were observed. Upon percutaneous induction incrustation, well-defined erythema and slight oedema were noted, but these were caused by the intradermal induction.

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

1,4-Dioxane did not show skin sensitising properties in a guinea pig maximisation test, performed according to EEC guidelines.

Available human data are too limited to draw conclusions (a case report on one man who developed dermatitis on his left hand after daily dipping in a 1,4-dioxane containing solvent for 3 years, that scored positive in a patch test).

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

No information available. However, respiratory tract sensitisation is not expected as 1,4-dioxane is not a skin sensitiser and no positive human data is available.

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No 1272/2008
The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. A well-conducted maximisation test in guinea pigs was negative. As a result the substance does not require classification for skin sensitisation under Regulation (EC) No 1272/2008, as amended for the twelfth time in Regulation (EU) 2019/521.