2,3-dihydrothieno[3,4-b][1,4]dioxine

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1.2.-8.2.2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study was carried out in accordance with internationally valid GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Name of test material (as cited in study report): 3,4-Ethylenedioxythiophene
- Comercial name. EDOT
- Substance type: pure organic substance
- Physical state: liquid near colourless to pale yellow
- Analytical purity: > 99%
- Lot/batch No.: 091201
- Expiration date of the lot/batch: 21.1.2011
- Storage condition of test material: Keep in dark at room temperature. Stored in amber glass bottles under the argon atmosphere. Minimalize time for handling with substance without protective argon atmosphere as possible. Maximal time without protective atmosphere is 30 min.
- pH: approximately 4 (by contact of application form with universal indicator pH strip moistened with water, strip producer Lach-Ner, s.r.o. (Neratovice)

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: breeding farm VELAZ s.r.o., Koleč u Kladna, Czech Republic, RČH CZ 21760152
- Weight at study initiation: 3.3-3.8 kg
- Housing: individually in cages without bedding in conventional animal room
- Diet (e.g. ad libitum): pelleted standard diet TM-MAK 1 for rabbits and guinea-pigs ad libitum (producer: Ing.Mrkvička Miroslav - Výroba krmných směsí, Mlýn Kocanda, 252 42 Jesenice u Prahy)
- Water (e.g. ad libitum): drinking tap water ad libitum (quality corresponding to Regulation No. 252/2004 Czech Coll. of Law)


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 - 23oC, permanently monitored
- Humidity (%): 30 – 70 %, permanently monitored
- Air changes (per hr): approximately 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12-hour light/dark cycle


STUDY TIME SCHEDULE
- Animal supply: 27. 01. 2010
- Experimental part of study: 01.02. – 08. 02. 2010

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 ml

Duration of treatment / exposure:

3 min, 1 hr, 4 hrs

Observation period:

1, 24, 48 and 72 hours

Number of animals:

3 animals

Details on study design:

TEST SITE
- Area of exposure: 6x6 cm
- Type of wrap if used: gauze patch, foil and cellulose cotton and held in place with non-irritating tape - Spofaplast.


REMOVAL OF TEST SUBSTANCE
- Washing (if done): with water
- Time after start of exposure: 3 min, 1 hr, 4 hrs


SCORING SYSTEM:
-According to method B.4 - Acute Toxicity: Dermal Irritation/Corrosion, Council Regulation (EC) No.440/2008, published in O.J. L 142, 2008.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24, 48, 72 hrs

Score:

0 - 1

Max. score:

4

Reversibility:

fully reversible

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24, 48, 72 hrs

Score:

0

Max. score:

4

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test substance, 3,4-Ethylenedioxythiophene, was tested for acute dermal irritation/corrosion.

Three rabbits were exposed to 0.5 ml of test substance, applied onto clipped skin for 4 hours using a semi-occlusive dressing. Skin reactions were evaluated after patch removal and observations were made at the 1, 24, 48 and 72 hours after exposure. Very slight skin irritation was observed in all animals at the 1 and 24 hours after application. At 48 and 72 hours after application no irritation of the skin was observed in all animals.

No symptoms of systemic toxicity were observed in the animals during the test period.
No skin irritation was caused by 4-hour exposure to 3,4-Ethylenedioxythiophene.

Executive summary:

The test substance, 3,4-Ethylenedioxythiophene, was tested in the study for acute dermal irritation/corrosion. Rabbits (New Zealand Albino breed) were used for the test.

Test was performed according to Method B.4 - Acute Toxicity: Dermal Irritation/Corrosion, Council Regulation (EC) No.440/2008, published in O.J. L 142, 2008.

Three rabbits were exposed to 0.5 ml of test substance, applied onto clipped skin for 4 hours using a semi-occlusive dressing. Skin reactions were evaluated after patch removal and observations were made at 1, 24, 48 and 72 hours after exposure.

At first the test substance was applied on the skin of one rabbit (test animal No. 1). Rabbit No. 1 was investigated 3 minutes, 1 hour and 4 hours after application of the test substance. Very slight oedema and very slight erythema was observed on the skin after 1hour and 4 hours. In confirmatory test, two others rabbits (rabbit No. 2 and No. 3) were used with 4-hour exposition period. Very slight erythema and very slight oedema was observed at the 1 hour after 4-hour exposure to the test substance in all animals. Very slight erythema was observed in two animals (rabbit No.1 and no.2) at the 24 hours after application. At the 48 and 72 hours after exposure no irritation of the skin was observed in all animals.

No skin irritation was caused by 4-hour exposure to 3,4-Ethylenedioxythiophene. No other signs of intoxication were observed.