Imidazolidine-2-thione

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2001/02/26 - 2001/08/03

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study (OECD 402)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

not specified

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Imidazolidine-2-thione

EC Number:

202-506-9

EC Name:

Imidazolidine-2-thione

Cas Number:

96-45-7

Molecular formula:

C3H6N2S

IUPAC Name:

imidazolidine-2-thione

Constituent 2

Reference substance name:

ethylenethiourea

IUPAC Name:

ethylenethiourea

Details on test material:

- Name of test material (as cited in study report): ETU
- Characteristics: light beige powder
- Assay (purity) = 99.6%
- Lot/batch No.: L33-99
- Storage condition of test material: at room temperature or colder

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland GmbH
- Age at study initiation: males = 42 days, females = 54 days
- Weight at study initiation: males = 203-235g, females = 208-227g
- Fasting period before study: 16 hours before administration
- Housing: singly in makrolon cages (type III)
- Diet (e.g. ad libitum): Altromin 1324, available before fasting period
- Water (e.g. ad libitum): yes, ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22+/-3°C
- Humidity (%):55+/-15%
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light):12/12

Administration / exposure

Type of coverage:

occlusive

Vehicle:

other: sesame oil

Details on dermal exposure:

TEST SITE
- Area of exposure: onto the shaved intact dorsal skin
- % coverage: 10% (5x6 cm, 1/10 of body surface)
- Type of wrap if used:
The tes suspension was applied to the shaved skin and the covered with 8 layers of gauze. The gauze was covered with a plastic sheet and secured with adhesive plaster on the application site.

REMOVAL OF TEST SUBSTANCE
At the end of the exposure period, possible residual substance was removed.

TEST MATERIAL
Administration : 10 ml ETU sesam oil suspension/ kg bw

VEHICLE
- Lot/batch no. (if required): 00D28FN
- Purity: no data

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 rats/ sexe /dose

Control animals:

no

Details on study design:

Observation period: 14 days
At the start of the experiment, the rats were weighed.
Observations of clinical signs were performed before and immediately, 5, 15, 30 and 60 min, as well as 3, 6 and 24 hours after administration.
During the follow-up period, changes of skin and fur, eyes and mucous menbranes, respiratory and the circulatory, autonomic and central nervous system and somatomotor activity as well as behaviour pattern were observed at least once day until all symptoms subsided, thereafter each working day. Attention was also paid to possible tremor, convulsions, salivation, diarrheoea, lethargy, sleep and coma.
Observations on mortality were made at least once daily with appropriate actions taken to minimize loss of animals during the study. Individual body weights were recorded before administration of the substance and thereafter in weekly intervals up to the end pf the study, and at death.
The skin was observed for the development of erythema and oedema.
At the end of the experiments all surviving animals were sacrified, dissected and inspected macroscopically. all gross pathological changes were recorded. From animals which survived 24 hours or longer a microscopic examination of all organs which showed evident lesions was performed, if necessary. Autopsy and macroscopic inspection of animals which died prematurely were carried out as soon as possible after exitus.

Statistics:

no

Results and discussion

Preliminary study:

No preliminary test was performed as it was known that the test substance possesses little toxicity.

Effect levels

Sex:

male/female

Dose descriptor:

LD0

Effect level:

>= 2 000 mg/kg bw

Based on:

test mat.

Mortality:

no mortality were observed.

Clinical signs:

other: Any clinical signs was observed. No influence on animal behaviour or premature mortality was noted. No skin reaction was observed (erythema score and edema score were equal to 0 at any test day).

Gross pathology:

The macroscopic examination of the internal organs did not reveal any changes.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: other: Regulation EC no.1272/2008

Conclusions:

Under the present test conditions a single dermal administration of 2000 mg/kg bw to rats revealed no toxic symptoms. The animals gained he expected body weight throught the test study period.

Executive summary:

The test substance was applied to rats dermally to obtain information on the possible effects in humans following overdosing with ETU.

Under the present test conditions a single dermal administration of 2000 mg/kg bw to rats revealed no toxic symptoms. The animals gained the expected body weight throught the test study period.