Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
31 January 1996 - 20 February 1996
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted to GLP in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1996
Report Date:
1996

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OTS 798.1175 (Acute Oral Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
other: Japan 59 NohSan Notification No. 4200
Deviations:
no
GLP compliance:
yes
Test type:
standard acute method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: solid
Details on test material:
MMBC
Appearance: tan-yellow solid

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Kingston, Stone Ridge, NY.
- Age at study initiation: Adult. Males were approximately 55 days old and the females were approximately 65 days old at the time they were dosed.
- Weight at study initiation: The fasted body weights ranged from 197 - 219 g for males and from 184 - 225 g for females.
- Fasting period before study: Overnight.
- Housing: The animals were individually housed in suspended stainless steel cages (7 x 13.5 x 8 in., i.e. 18 x 34 x 20 cm) with wire mesh fronts and bottoms. Cages were suspended above absorbent-paper pan liners which were changed 3 times a week.
- Diet (e.g. ad libitum): PMI Certified Rodent Diet 5002(C) (Purina Mills Inc., Richmond, IN).
- Water (e.g. ad libitum): Free access to filtered tap water (via automatic watering).
- Acclimation period: Approximately one week.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 °C
- Humidity (%): 41 - 49 %
- Photoperiod (hrs dark / hrs light): The light cycle was automatically controlled, 12 hrs on and 12 hrs off.

IN-LIFE DATES: From: To: 6 February 1996 - 20 February 1996

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on oral exposure:
The test substance was dosed in a corn oil suspensions at a constant volume of 10 mL/kg body weight.

The test substance was melted in an oven at 60°C. Corn oil (warmed to 40°C) was added to the appropriate volume and a suspension was attained using a magnetic stir plate and a stir bar. The suspension (kept stirring while dosing) was administered to male and female rats at 500, 2000, and 5000 mg/kg. Dose was calculated from nominal values with no adjustment made for percent active ingredient. All animals were dosed within 1 hour of preparation of the suspensions. Samples were collected after dose administration and submitted for subsequent analytical verification of the target concentration.
Doses:
500, 2000 and 5000 mg/kg
No. of animals per sex per dose:
6 males and 6 females per dose.
Control animals:
no
Details on study design:
OBSERVATIONS AND DETERMINATIONS
All animals were observed for signs of ill health, or reaction to treatment at 1, 2 and 4 hrs after dosing and once daily thereafter for 14 days. Body weights were recorded on day 0 (prior to dosing) and on days 7 and 14. Body weights were determined for found-dead animals when they survived beyond the day of treatment. Decedents were necropsied as death occurred. Surviving rats were killed on day 14 and necropsied.

Necropsy consisted of a gross examination of organs in situ.
Statistics:
The mortality incidences of males and females were compared across doses with a categorical data modeling procedure using SAS CATMOD (SAS Institute Inc. SAS User's Guide: Statistics, Version 6 Edition, p 405-517. Cary, NC: SAS Institute Inc., 1990). The criterion of statistical significance was 0.05. The LD50 was calculated on the pooled mortality incidences at each dose.

The LD50 and 95% confidence limits were calculated based on the binomial distribution.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
3 162 mg/kg bw
Based on:
test mat.
95% CL:
2 000 - 5 000
Remarks on result:
other: Analysis of the dosing suspensions indicated a 97 - 105 % proximity to target concentration.
Mortality:
Dose-related mortality was observed in this study (Table 1). The total mortality incidences (no. deaths/no. treated) for males and females in this study were as follows:

Dose (mg/kg) 500 2000 5000
Males 0/6 0/6 6/6
Females 0/6 0/6 6/6

All animals in the 5000 mg/kg dose group died by day 1.
Since there was not a statistically significant sex-related difference in mortality, the LD50 was calculated from the combined male and female mortality incidence data.
Clinical signs:
Treatment-related clinical signs were observed predominantly at 2000 and 5000 mg/kg and included: diarrhoea, mucus in faeces, scant faeces, passiveness, ataxia, red/tan-stained muzzle, pink-stained dropsheet, brown/yellow-stained analgenital area, lacrimation, and prostration (Table 1).
Body weight:
There was a slight decrease in body weight gain among males at 500 mg/kg (13%) and 2000 mg/kg (18%) when compared to historical control data. No body weight effects were noted in females in either dose group.
Gross pathology:
No gross changes related to the test substance were observed in survivors at necropsy. One male in the 2000 mg/kg group had a dilated renal pelvis; however, this finding was considered incidental and not related to the test substance.
Necropsy of the decedents revealed liver, spleen and various gastrointestinal changes related to the test substance (Table 2).

Any other information on results incl. tables

Table 1 Mortality and Clinical Signs

Males

Dose

(mg/kg)

Observation

Hours

Days

1

2

4

1 - 14

 

 

500

No. Alive

6

6

6

6

No. Dead

0

0

0

0

Normal

5

5

5

6

Analgenital area (brown-stained)

1

1

0

0

Diarrhoea

1

1

1

0

Faeces: contain mucus

1

1

1

0

 

 

2000

No. Alive

6

6

6

6

No. Dead

0

0

0

0

Normal

5

6

3

6

Diarrhoea

1

0

3

0

 

 

5000

No. Alive

3

6

2

0

No. Dead

0

0

4

6

Normal

6

0

0

0

Passive

0

5

1

 

All animals died by Day 1.

Prostrate

0

1

0

Dropsheet (pink-stained)

1

1

1

 

Females

Dose

(mg/kg)

Observation

Hours

Days

1

2

4

1

2

3

4 - 14

 

 

500

No. Alive

6

6

6

6

6

6

6

No. Dead

0

0

0

0

0

0

0

Normal

2

2

3

6

6

6

6

Analgenital area (brown-stained)

2

4

2

0

0

0

0

Diarrhoea

4

3

3

0

0

0

0

Faeces: contain mucus

3

3

2

0

0

0

0

 

 

 

 

 

 

2000

No. Alive

6

6

6

6

6

6

6

No. Dead

0

0

0

0

0

0

0

Normal

3

4

4

3

4

5

6

Diarrhoea

3

2

2

0

0

0

0

Faeces: contain mucus

1

2

0

0

0

0

0

Faeces: scant

0

0

0

1

2

0

0

Lacrimation

0

0

1

0

0

0

0

Passive

0

0

2

1

0

0

0

Ataxic

0

0

1

0

0

0

0

Muzzle: tan-stained fur

0

1

1

0

0

0

0

Muzzle: red-stained fur

0

0

0

1

1

0

0

Analgenital area (brown/yellow-stained)

1

2

1

3

1

1

0

 

 

 

5000

No. Alive

6

5

2

0

No. Dead

0

1

4

6

Normal

4

0

0

0

 -

Passive

2

4

0

 

 

All animals died by Day 1.

Prostrate

0

1

0

Dropsheet (pink-stained)

0

1

0

Ataxic

0

1

0

Moribund

0

0

2

 

Table 2 Necropsy Observations

Males

Dose (mg/kg)

500

2000

5000

S

D

S

D

S

D

No. of Animals

6

0

6

0

0

6

No. Gross Changes

6

a

5

a

b

0

Observations

Intestines (reddened)

0

a

0

a

b

1

Liver (brown area on left lobe)

0

a

0

a

b

3

Stomach (distended)

0

a

0

a

b

4

Stomach (contains black fluid/material)

0

a

0

a

b

6

Stomach (black material adhered to mucosa)

0

a

0

a

b

6

Kidney (right dilated renal pelvis)

0

a

1

a

b

0

S - Survivors

D - Decedents

a - No observations located in this column because there were no decedents.

b - No observations located in this column because there were no survivors.

 

Females

Dose (mg/kg)

500

2000

5000

S

D

S

D

S

D

No. of Animals

6

0

6

0

0

6

No Gross Changes

6

a

6

a

b

0

Observations

Intestines (reddened)

0

a

0

a

b

1

Liver (brown area on left lobe)

0

a

0

a

b

1

Spleen (darkened)

 

 

 

 

 

3

Stomach (distended)

0

a

0

a

b

3

Stomach (contains black fluid)

0

a

0

a

b

6

Stomach (black material adhered to mucosa)

0

a

0

a

b

6

S - Survivors

D - Decedents

a - No observations located in this column because there were no decedents.

b - No observations located in this column because there were no survivors.

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The acute oral LD50 in male and female rats (combined) was 3162 mg/kg, with upper and lower 95% confidence limits of 2000 and 5000 mg/kg, respectively.
Executive summary:

The acute oral toxicity of the test substance was determined in accordance with standardised guidelines OECD 401, US EPA OPPTS 798.1175 and Japan 59 NohSan Notification No. 4200. During the study groups of 6 males and 6 females received a single administration of test substance, orally by gavage, at dose levels of 500, 2000 or 5000 mg/kg bodyweight and were assessed daily for the following 14 days for any signs of systemic toxicity. Under the conditions of the study, there was 100% mortality within 24 hours post-dosing for all animals treated at 5000 mg/kg. No deaths occurred in either sex at 500 and 2000 mg/kg. Treatment-related clinical signs were observed predominantly at 2000 and 5000 mg/kg and included: diarrhoea, mucus in faeces, scant faeces, passiveness, ataxia, red/tan-stained muzzle, pink-stained dropsheet, brown/yellow-stained analgenital area and lacrimation. A slight decrease in body weight gain was noted in males at 500 mg/kg and 2000 mg/kg; however, no body weight effects were noted in females in either dose group. Necropsy of the decendents revealed gastrointestinal, spleen and liver changes related to the test substance. Since there was not a statistically significant sex-related difference in mortality, the LD50 was calculated from the combined male and female mortality incidence data. The acute oral LD50 in male and female rats (combined) was 3162 mg/kg, with upper and lower 95% confidence limits of 2000 and 5000 mg/kg.