Cyclohexanamine, 4,4'-methylenebis[N-(1-methylpropyl)-

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April 7, 2005 - May 28, 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to OECD Guideline 402 and EPA OPPTS 870.1200 with acceptable restrictions (less than three dose levels were used) and in compliance with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

, less than three dose levels were used

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

, less than three dose levels were used

GLP compliance:

yes

Test type:

other: Acute dermal toxicity study with two dose levels.

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

N-(butan-2-yl)-4-({4-[(butan-2-yl)amino]cyclohexyl}methyl)cyclohexan-1-amine

EC Number:

679-514-8

Cas Number:

154279-60-4

Molecular formula:

C21H42N2

IUPAC Name:

N-(butan-2-yl)-4-({4-[(butan-2-yl)amino]cyclohexyl}methyl)cyclohexan-1-amine

Details on test material:

- Name of test material (as cited in study report): Clearlink 1000
- Physical state: Clear colorless to pale yellow liquid.
- Batch No.: CL-29720041
- Storage condition of test material: Room temperature.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Texas Animal Specialities, Humble, TX.
- Age at study initiation: 8 weeks.
- Weight at study initiation: 255-306 g (males) and 176-200 g (females)
- Fasting period before study: No
- Housing: Suspended, wire bottom, stainless steel cages I per cage.
- Diet (e.g. ad libitum): PMI Feeds Inc. Formula # 5008 ad libitum.
- Water (e.g. ad libitum): Tap water ad libitum.
- Acclimation period: 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ±3 °C
- Humidity (%): 30-70%
- Air changes (per hr): 10-12 air changes/hour.
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle.

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: Not less than 10% of the total body surface area.
- Type of wrap if used: The area of application was covered with a 2 x 4 in. surgical gauze patch and secured with non-irritating adhesive tape. The trunk of each animal was then wrapped with vet wrap which was secured in place with non-irritating adhesive tape to prevent possible ingestion of the test substance.

REMOVAL OF TEST SUBSTANCE
- Washing: The test sites were gently washed with room temperature tap water and a clean cloth to remove as much residual test substance as possible.
- Time after start of exposure: 24 hours.

Duration of exposure:

24 hours

Doses:

1600 mg/kg and 2000 mg/kg

No. of animals per sex per dose:

5 males and 5 females per dose

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days.
- Frequency of observations and weighing: Observations for mortality and clinical/behavioural signs of toxicity were made at least three times on the day of dosing (Day 0) and at least once daily thereafter for 14 days. Observations for evidence of dermal irritation were made at approximately 60 minutes after removal of wrapping, and on Days 4, 7, 11 and 14. Individual body weights were recorded just prior to dosing and on Day 7 and 14, or at the time of discovery after dearth.
- Necropsy of survivors performed: yes. On Day 14 after dosing, surviving animals were euthanized by an overdose of CO2. All study animals, whether dying during the study or euthanized, were subject to gross necropsy and all abnormalities were recorded.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 1 600 - < 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Individual mortality data, including time of death, are presented in Table 1, which is attached as background material. A summary of the incidences:
Dosage (mg/kg), Males, Females, Combined (number dead/number treated)
1600, 0/5, 0/5, 0/10
2000, 3/5, 5/5, 8/10

Clinical signs:

other: Prominent in-life observations included activity decrease, hunched posture, prolapsed penis and lateral recumbency. Signs were observed on Days 1 through 14. Clinical signs are presented in Table 2 which is attached as background material.

Gross pathology:

Gross necropsy in animals that died on test revealed crusted fur, black skin at test site, discoloured liver and contents of the small intestine, and empty stomach and intestines. Gross necropsy in animals surviving to termination of the study revealed no observable abnormalities. Individual necropsy findings are presented in Table 1, which is attached as background material.

Other findings:

Irritation included very slight to severe erythema, very slight to slight oedema, atonia, focal bleeding, coriaceousness, desquamation, eshar, blanching, alopecia, necrosis, ulceration and bruising through Day 14. Signs of dermal irritation are presented in Table 3, which is attached as background material.

Applicant's summary and conclusion

Interpretation of results:

harmful

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Clearlink 1000 was evaluated for its acute dermal toxicity potential and relative skin irritancy by applying it as undiluted single dose to the intact skin of albino rats at dose levels 1600 and 2000 mg/kg. The study was performed in compliance with GLP and the test method was similar to OECD 402 (only two dose levels used instead of required three).

No mortality occurred at the 1600 mg/kg dose level. 3/5 males and 5/5 females died at dose level 2000 mg/kg. clinical signs included activity decrease, hunched posture, lateral recumbency and prolapsed penis. Signs of dermal irritation included erythema, edema, atonia, focal bleeding, coriaceousness, desquamation, eschar, alopecia, blanching, necrosis, ulceration and bruising. 4 animals lost weight during the first week of the study in the 1600 mg/kg dose group, and the only two living animals in the 2000 mg/kg group lost weight during the first week of the study. Abnormal necropsy findings occurred only in the animals dying during the study, and pertained to fur, skin, liver and content of the gastrointestinal tract. The estimated LD50 value for acute dermal toxicity was greater than 1600 mg/kg, but less than 2000 mg/kg. Because the calculation of a single LD50 value is not possible, a conservative approach is taken and 1600 mg/kg bw is selected as a discriminating dose.

The results of this study would lead to the classification of acute oral toxicity (Xn; R21) in accordance with the criteria set in Directive 67/548/EEC. According to EU Regulation No. 1272/2008 (CLP), the classification would be acute tox cat 4; Harmful in contact with skin.

The study is classified as acceptable but as it is conducted with only two doses, instead of the required minimum of three, it does not full fill the guideline requirements. However, it offers important information for evaluation and in the absence of other data, it is used for classification. In addition, according to column 2 of REACH Annex VIII Section 8.5, testing of acute dermal toxicity is not required as Clearlink 1000 has corrosive properties. The result of this study is used as a key value in hazard assessment.