diuron (ISO); 3-(3,4-dichlorophenyl)-1,1-dimethylurea

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1983

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1983

Report date:

1983

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

(1984)

Deviations:

yes

Remarks:

, only minor reporting deficiencies, which do not affect the validity of the study

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Diuron

EC Number:

206-354-4

EC Name:

Diuron

Cas Number:

330-54-1

Molecular formula:

C9H10Cl2N2O

IUPAC Name:

3-(3,4-dichlorophenyl)-1,1-dimethylurea

Details on test material:

- Name of test material (as cited in study report): Diuron technical
- Purity test date: 98.8%
- Lot/batch No.: 232114080

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann, Borchen, Germany
- Weight at study initiation: 160 - 200 g
- Housing: conventional Makrolon cages, 5 animals per cage
- Diet (e.g. ad libitum): "Altromin diet for rats and mice"
- Water: ad libitum
- Acclimation period: at least 3 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 -25
- Humidity (%): 40 - 60
- Photoperiod (hrs dark / hrs light): 12 h dark/ 12 h light

Administration / exposure

Type of coverage:

occlusive

Vehicle:

physiological saline

Details on dermal exposure:

TEST SITE
- Area of exposure: dorsal skin
- Type of wrap if used: occusive dressing (method is according to Noakes and Sanderson (1969)

REMOVAL OF TEST SUBSTANCE
- Washing (if done): with water and soap
- Time after start of exposure: 24 h

Duration of exposure:

24 h

Doses:

2500 and 5000 mg/kg body weight

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

No animals died during the observation period.

Clinical signs:

other: Application of 2500 mg/kg body weight was tolerated without any sings of toxicity. At 5000 mg/kg bw, reduced motility and apathy was observed lasting for 2 – 4 days. No macroscopic changes of skin were noted.

Gross pathology:

Sacrificed animals at study termination showed no evidence of macroscopical changes in organs.

Any other information on results incl. tables

Table 1: Acute dermal toxicity of Diuron (male and female rats)

Dose (mg/kg bw)	Number of dead / number investigated	Time of death (range)	Observations
2500	0/10	-	None
5000	0/10	-	Reduced motility, apathy for 2 – 4 days
LD50value	> 5000 mg/kg bw

Applicant's summary and conclusion

Executive summary:

In a reliable study in accordance to OECD 402 rats were dermally exposed to 2500 and 5000 mg/kg bw Diuron. At the low dose level no clinical signs were noted and at the high dose level animals only showed reduced motility and apathy for 2 to 4 days. Therefore, the LD50 is determined to be > 5000 mg/kg bw. (Heimann and Thyssen, 1983)