4,4'-methylenebis(cyclohexylamine)

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1987-08-03 to 1987-09-22

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EPA OPP 81-1 (Acute Oral Toxicity)

Version / remarks:

1984

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-methylenebis(cyclohexylamine)

EC Number:

217-168-8

EC Name:

4,4'-methylenebis(cyclohexylamine)

Cas Number:

1761-71-3

Molecular formula:

C13H26N2

IUPAC Name:

4,4'-methylenedicyclohexanamine

Details on test material:

PACM 48 is a solid material.
Isomer content: 48% trans-trans

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS:
- Source: Buckshire Corp., Perkasie, PA 18944
- Strain: Sprague-Dawley rat
- Sex: male and female
- Weight: 200- 300 g
- Housing: The animals were housed and mainained in accordance with standards set forth in the Guide for the Care and Use of Laboratory Animals (NIH Publication No. 86-23)
- Acclimation period: at least 5 days prior to dosing, stainless steel elevated wire mesh flooring, 3-5 rats/ cage by sex
- Diet (ad libitum): Wayne Rodent-Blox
- Water (ad libitum): tap water
- Fasting period before study: the animals were deprived of food but not water over night prior to dosing

ENVIRONMENTAL CONDITIONS
- Temperature: 70- 80 °F
- Relative humidity: 30- 80 %
- Light: 12 hour light/ dark cycle

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 10% ethanol and corn oil

Details on oral exposure:

The test item was dosed as an 10 % (w/v) suspension in 10 % ethanol and corn oil.

Doses:

- males: 100, 250, 500, 562, 708, 1000 mg/kg
- females: 100, 250, 398, 500, 631 mg/kg

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

The laboratory rat was the system of choice since it is required in the federal guideline for this study and in addition has a long history of use for this kind of study.
Following the administration, the animals were allowed food and water ad libitum for the 14 days observation period during which the rats were observed for signs of toxicity and mortality. Animals were observed frequently on the day of dosing, twice per day on week days and once per day on weekends and holidays.
Individual weights were recorded on the day of dosing, weekly thereafter and prior to sacrifice. The animals were euthanized at the conclusion of the observation period. Gross necropsies were performed on all animals.

Statistics:

The LD 50 and its 95 % confidence interval were calculated employing the Litchfield & Wilcoxon Method (Litchfield, J.T. and Wilcoxon F., "A Simplified Method of Evaluating Dose-effect Experiments", J. Pharmacol. Exp. Ther. 96:99-115, 1949).

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

480 mg/kg bw

Based on:

test mat.

95% CL:

> 360 - < 650

Effect levels 2

Sex:

female

Dose descriptor:

LD50

Effect level:

350 mg/kg bw

Based on:

test mat.

95% CL:

> 260 - < 470

Effect levels 3

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

380 mg/kg bw

Based on:

test mat.

95% CL:

> 270 - < 550

Mortality:

MALES:
No deaths occured in the dose groups 100 mg/ kg bw and 250 mg/ kg bw.
1/5 animals died in the 500 mg/ kg bw dose group on day 1.
2/5 animals died in the 562 mg/ kg bw dose group on day 1.
5/5 animals died in the 708 mg/ kg bw and 1000 mg/ kg bw dose groups.

FEMALES:
No deaths occured in the dose groups 100 mg/ kg bw and 250 mg/ kg bw.
3/5 animals died on day 1 in the 398 mg/ kg bw dose group.
4/5 animals died in the 500 mg/ kg bw dose group, 3 on day 1 and 1 on day 2.
5/5 animals dies in the 631 mg/ kg dose group, 4 on day 1 and 1 on day 7.

Clinical signs:

other: Males: 100 and 250 mg/kg : ruffled appearance on day 1 500 mg/kg: ruffled appearance and (dark) nasal staining on the first 3 days 562 mg/kg: ruffled appearance, piloerection, genital staining, convulsions, stained body, dark nasal staining, muzzle stai

Gross pathology:

No treatment-related macroscopic findings were noted in the surviving animals. In the animals found dead, following observations were made:
FEMALES:
398 g/ kg bw, animal 1: spongy hemorrhagic lungs and gas in the stomach, animal 2: ocular discharge, dark nasal discharge, hemorrhagic lungs and dark liquid in the lower gastrointestinal tract, animal 3: oral and nasal discharge, spongy hemorrhagic lungs and injected stomach vessels.

500 mg/ kg bw, 2 animals found dead on day 1: hemorrhagic lungs, injected stomach vessels and a hemorrhagic stomach lining, animal 3: dark kidneys, injected stomach vessels, dark red swollen areas on the stomach lining and dark red liquid in the large intestines, animal 4: red nasal and oral discharge, a pale liver, injected stomach vessels, gas in the stomach, dark tarry material in the large intestines and yellowish material in the small intestines.

631 mg/ kg bw, 3 animals found dead on the initial day of dosing: injected stomach vessels, an irritated stomach lining and dark liquid in the stomach and lower gastrointestinal tract, animal 4: injected stomach vessels and dark liquid in the stomach and lower gastrointestinal tract, animal 5: pale liver, dark kidneys, dark liquid in the stomach and lower gastrointestinal tract.

MALES:
500 mg/ kg bw, animal 1: hemorrhagic lungs, injected stomach vessels and hemorrhagic areas on the stomach lining.

562 mg/ kg bw, animal 1: nasal discharge, pale lungs, injected stomach vessels, yellow material in the stomach and dark liquid in the lower gastrointestinal tract, animal 2: stained muzzle, 50 % of the stomach lining appeared irritated, liquid in the stomach and lower gastrointestinal tract, animal 3: bloated stomach containing food, adhesions between the stomach and abdominal wall, a possible blockage of the upper gastrointestinal tract.

708 mg/ kg bw, 5/5 animals: injected stomach vessels, an irritated stomach lining and dark liquid in the stomach and lower gastrointestinal tract.

*)

Other findings:

*) 1000 mg/ kg, 5/5 animals: pale lungs and kidneys, injected stomach vessels, orrotation of 30 % of the stomach lining and dark liquid in the lower gastrointestinal tract

Applicant's summary and conclusion

Conclusions:

The LD50 of 4-4’-methylenedicyclohexanamine by oral gavage to Sprague-Dawley rats is 380 mg/kg bw.

Executive summary:

The test material was tested in an acute oral toxicity study with 55 male and female albino rats.

The animals were deprived of food but not water overnight prior to dosing. Each animal was weighted and dosed by directly administration of the test material, as prepared, into the stomach by gavage. During the 14 day observation period, the animals were observed for signs of toxicity and mortality and individual weights were recorded. All males which died were dead on day 1. The deaths occured in the two highest dose groups. All deaths of the females occured on day 1, except for 1 female given 500 mg/kg on day 2 and 1 female given 631 mg/kg on day 7. Clinical signs in all dose groups were ruffled appearance. In the higher dose groups of male animals also piloerection, genital staining, convulsions, stained body, dark nasal staining, muzzle staining and/or lethargy during the observation period occured. In the hihgest dose groups the male animals were comatose and died on day one. Females showed gasping immediately after dosing, ruffled appearance, lethargy and/or piloerection between days 1 and 8. No treatment-related macroscopic findings were noted in the surviving animals. In animals found dead the following observations were made: signs of irritated stomach, dark liquid in the stomach and lower gastrointestinal tract, pale lungs and kidneys, pale liver and/or hemorrhagic lungs.