2,2-dimethyl-1,3-dioxane-4,6-dione

Endpoint summary

Description of key information

The substance was classified as non-irritant to skin and as irritant Cat.2 to eyes.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March 1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: the study was performed before GLP- and OECD-testing guidelines were available and in force; therefore the study was considered to have Klimisch 2, however it provides enough information to assess the acute toxicity to rats after oral application

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Morton Commercial Rabbits, Parsonage Farm, Stansted, Essex, UK
- Age at study initiation: no data
- Weight at study initiation: 2.0 - 3.5 kg
- Diet (e.g. ad libitum): Food (Rabbit Pellets C, Spillers Agriculture Ltd., Old Change House, Canon Street, London)
- Water (e.g. ad libitum): Mains water was provided and dipensed from glass water bottles
- Acclimation period: 7 days
- Housing: caged individually in grid floor cages

ENVIRONMENTAL CONDITIONS
- Temperature (°C): not controlled except that a lower limit of 14°C was automatically imposed
- Humidity (%): not controlled
- Air changes (per hr): fan controlled air circulation
- Photoperiod (hrs dark / hrs light): natural lighting supplemented with fluorescent lighting during working hours (06.00 - 20.00)

Type of coverage:

semiocclusive

Preparation of test site:

abraded

Vehicle:

water

Controls:

no

Amount / concentration applied:

The test article was moistened with water and applied as a paste. Portions of the test article (0.5 g) were applied.

Duration of treatment / exposure:

4 hours

Observation period:

4, 24, 48 and 72 hours after treatment

Number of animals:

6 animals

Details on study design:

APPLICATION TEST ARTICLE:
Twenty-four hours prior to treatment, the back of each animal was clipped free of hair using veterinary clippers (Model A2, aster, Milwaukee, Wisconsin). One side of the clipped area on each animal was left intact. The other side was abraded using a clipper head to penetrate the horny layer of the epidermis, but without causing bleeding or damage to the underlying dermis.
Portions of the test article (0.5 g) were applied to 1 intact and 1 abraded site on each animal and covered with patches of gauze (25 mm x 25 mm). A small plug of cotton wool weighing approximately 1 g was placed over the top of the pads to achieve uniform pressure over the whole treatai surface. The pads were held in place by a strip of adhesive impermeable plaster, (Sleek, Smith and Nephew Ltd., Welwyn Garden City, Herts). An Elizabethan collar was placed around the neck of each animal to prevent removal of the wrapping. Four hours after treatment the wrappings and collars were removed.

SCORING SYSTEM:
According to Food and Drug Administration "Appraisal of the Safety of Chemicals in Focxls, Drugs and Cosmetics", 1959.) The scores for
erythema and oedema were used to calculate the primary irritation index of the test article

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24-72h

Score:

0.2

Max. score:

1

Reversibility:

not fully reversible within: 72h

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24-72h

Score:

0.1

Max. score:

1

Reversibility:

not fully reversible within: 72h

Irritant / corrosive response data:

ERYTHEMA:
5/6 animals showed a score of 0 over the observation period of 24-72h.
1/6 animal showed a score of 1 over the observation period of 24-72h. Not fully reversible within: 72h

OEDEMA:
5/6 animals showed a score of 0 over the observation period of 24-72h.
1/6 animal showed a score of 0.7 over the observation period of 24-72h. Not fully reversible within: 72h

Interpretation of results:

slightly irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The substance was classified as non-irritant to skin

Executive summary:

A study was carried out equivalent or similar to OECD Guideline 404 (skin irritation) on six NZW rabbits. The test was performed in 1980 as GLP-study according to OECD 404. Six albino rabbits were treated semi-occlusive with 0.5 g test item applied on a 25 x 25 mm gauze covered with patches. Observation times were 24, 48 and 72 hours after removal of the patch. Slight erythema and oedema were observed in one out of six animals, resulting in a primary irritation index of 0.4. The substance was classified as non-irritant to skin.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for selection of skin irritation / corrosion endpoint:
Klimisch 2 study; test design equivalent or similar to OECD 401

Justification for selection of eye irritation endpoint:
No study available; however based on pH-value, chemical structure, handling experience and CLP-data from other companies, it needs to be assumed that the substance is moderately irritating to eyes.

Effects on eye irritation: moderately irritating

Justification for classification or non-classification

Based on the data available the substance the substance needs to be classified or labeled according to Directive 67/548/EEC (DSD) or Regulation 1272/2008/EC (CLP) as follows:

CLP:

Warning

Eye irritation, Cat.2

DSD:

Irritant

R36