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Toxicological information

Acute Toxicity: oral

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Administrative data

Endpoint:
acute toxicity: oral
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:
OECD Guideline 401 (Acute Oral Toxicity)
Version / remarks:
1984
GLP compliance:
not specified
Test type:
acute toxic class method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Substance type: organic
- Physical state: white to yellowish solid
- Analytical purity: 98.8%
- Lot/batch No.: 232114080

Test animals

Species:
rat
Strain:
Wistar
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Winkelmann, Borchen, Germany
- Weight at study initiation: 160 - 200 g
- Fasting period before study: over night
- Housing: conventional Makrolon cages, 5 animals per cage
- Diet: "Altromin Diet for rats and mice"
- Acclimation period: at least three days

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

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
other: distilled water with Cremophor EL
Details on oral exposure:
VEHICLE
- Concentration in vehicle: Cremophor EL (5 drops/10 mL distilled water)
Doses:
25, 50, 1000, 2500, 5000 and 7100 mg/kg bw
total volume applied: 1 mL/100 g b.w.
No. of animals per sex per dose:
10 per group
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs

Method of determination of LD50: Litchfield & Wilcoxon (1949)

Results and discussion

Effect levels
Sex:
female
Dose descriptor:
LD50
Effect level:
4 150 mg/kg bw
Based on:
test mat.
Mortality:
Mortalities occurred at 2500 mg/kg and above within 2 days.
Clinical signs:
At the lowest dose level, no clinical signs were noted.
Higher dose levels revealed behavioural, respiratory and motility disorders.
Some animals exhibited a narcosis-like state and lying on side or stomach.
Signs were noted between 27 min (high dose levels) and 2 hours at lower doses following administration
Gross pathology:
Sacrificed animals at study termination showed a dark and slightly enlarged spleen.
In animals that died during the entire study, gross pathological findings were:
patchy, distended lungs, patchy spleen, liver and kidneys, reddened glandular stomach, dark spleen

Applicant's summary and conclusion

Executive summary:

In a reliable acute toxicity study comparable to guideline OECD 401 female rats were dosed with 25, 50, 100, 2500, 5000 and 7100 mg/kg bw Diuron (Heimann and Thyssen, 1983). At the lowest dose level, no clinical signs were noted. Higher dose levels revealed behavioural, respiratory and motility disorders. Some animals exhibited a narcosis-like state and lying on side or stomach. Signs were noted between 27 min (high dose levels) and 2 hours at lower doses following administration. Mortalities occurred at 2500 mg/kg and above within 2 days. Therefore, the LD50 was calculated to be 4150 mg/kg bw.