thiourea; thiocarbamide

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1978

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Thiourea

EC Number:

200-543-5

EC Name:

Thiourea

Cas Number:

62-56-6

Molecular formula:

CH4N2S

IUPAC Name:

thiourea

Test material form:

solid: particulate/powder

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: No data
- Age at study initiation: Young adults
- Weight at study initiation: 2.5 to 3.08 kg
- Fasting period before study: No
- Housing: Individually
- Diet: Ad libitum
- Water: Ad libitum
- Acclimation period: No data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 °C

Administration / exposure

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: 10 % of total body area
- % coverage: 10 %
- Type of wrap if used: Thin layer of cellulose sheet wrapped in polyethylene foil

REMOVAL OF TEST SUBSTANCE
- Washing: The test substance was removed from the skin with water
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount applied: 9 mL/kg body weight
- Constant volume or concentration used: Yes (constant volume: 9 mL/kg body weight)

VEHICLE
- Amount applied: The test substance was applied as solution in water (9 mL/kg)

Duration of exposure:

24 h

Doses:

0, 1.0, 2.0 and 2.8 g/kg body weight

No. of animals per sex per dose:

2 animals per sex and dose (altogether 8 males and 8 females)

Control animals:

yes, concurrent vehicle

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: At day 0, and at the end of week 1 and 2
- Necropsy of survivors performed: Yes
- Other examinations performed: Clinical signs, microscopic pathology (treated skin, liver, heart, kidneys), food consumption, water intake, body weights, haematological data, autopsy, histological examination of fixed organs (heart, liver, kidney, spleen).

Statistics:

none

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 800 mg/kg bw

Based on:

test mat.

Mortality:

No mortality

Clinical signs:

other: Slight erythema of the skin of rabbits treated with 2000 or 2800 mg/kg

Gross pathology:

No gross changes that could be related to the treating

Other findings:

None

Any other information on results incl. tables

Table 1: Individual body weights of male and female rabbits after a single dermal application of thiourea

Animal number and sex	Dose g/kg	Condition of skin	Body weights (in kg)
			At day 0	At the end of week 1	At the end of week 2
6336 M	0	Abraded	3.08	3.00	3.24
6338 M	0	Intact	2.80	2.83	2.93
6348 F	0	Abraded	2.83	2.82	3.00
6352 F	0	Intact	2.50	2.57	2.84
6337 M	1	Abraded	3.07	2.96	3.24
6343 M	1	Intact	2.84	2.85	2.97
6346 F	1	Abraded	2.6	2.35	2.50
6353 F	1	Intact	2.78	2.55	2.90
6340 M	2	Abraded	2.81	2.73	2.88
6341 M	2	Intact	3.05	3.04	3.12
6349 F	2	Abraded	2.66	2.68	2.94
6351 F	2	Intact	2.75	2.35	2.78
6334 M	2.8	Abraded	2.93	2.94	3.04
6339 M	2.8	Intact	2.88	2.86	3.00
6345 F	2.8	Abraded	2.70	2.60	2.91
6350 F	2.8	Intact	2.70	2.43	2.70

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Thiourea is practically non-toxic in rabbits, when applied dermally at a single dose of up to 2.800 mg/kg.

Executive summary:

In an acute dermal toxicity study, groups of young adult New Zealand White albino rabbits (8/sex) were dermally exposed to thiourea in water for 24 hours, covering 10 % of body surface area at doses of 0, 1000, 2000 and 2800 mg/kg bw. Animals were subsequently observed for 14 days. No mortality occured at the highest dose of 2800 mg/kg bw.

Thiourea is practically non-toxic when applied in a single dose to the skin of rabbits.