1-butyl-2,3-dicyclohexyl-1-methylguanidine

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 14 March 2008 to 29 July 2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with acceptable restrictions: the rationale of dose-selection is not fully compliant with guidelines requirements, however a worst-case strategy has been adopted.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

yes

Remarks:

rationale for dose-selection not fully compliant with guideline requirements

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

yes

Remarks:

rationale for dose-selection not fully compliant with guideline requirements

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS: Sprague-Dawley Rj:SD (IOPS Han)
- Source: Janvier, Le Genest-Saint-Isle, France
- Age at study initiation: approximately 8 weeks old
- Weight at study initiation: 214 +/- 7 g
- Fasting period before study: Animals were fasted for an overnight period of approximately 18 hours before dosing, but had free access to water.
- Housing: polycarbonate cages with stainless steel lid (48 cm x 27 cm x 20 cm). Each cage contained one to seven animals during the acclimation period and three rats of the same group during the treatment period.
- Diet: SSNIFF R/M-H pelleted maintenance diet batch Nos. 3016578 and 4676744 (SSNIFF Spezialdiäten GmbH, Soest, Germany) ad libitum
- Water: Drinking water filtered by a FG Millipore membrane (0.22 micron) ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 22 +/- 2 °C
- Humidity: 30 to 70 %
- Air changes: approximately 12 cycles per hr of filtered, non-recycled air
- Photoperiod (hrs dark / hrs light): 12 h/12 h (7:00 - 19:00)

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 5 and 30 mg/mL
- Amount of vehicle: 10 mL/kg bw
- Lot/batch no.: 126K0117 (Sigma, Saint-Quentin Fallavier, France)

CLASS METHOD
- Rationale for the selection of the starting dose: As no information on the toxic potential of the test item was available, for animal welfare reasons, the starting dose-level of 300 mg/kg was chosen.

Doses:

300 mg/kg bw , 50 mg/kg bw

No. of animals per sex per dose:

3 females/step

Control animals:

no

Details on study design:

Food was given back approximately 4 hours after administration of the test item
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed frequently during the hours following administration of the test item, for detection of possible treatment-related clinical signs. Thereafter, observation of the animals was made at least once a day. The animals were weighed individually just before administration of the test item on day 1 and then on days 8 and 15.
- Necropsy of survivors performed: yes. All study animals were subjected to a macroscopic examination as soon as possible after death.
After opening the thoracic and abdominal cavities, a macroscopic examination of the main organs (digestive tract, heart, kidneys, liver, lungs, pancreas, spleen and any other organs with obvious abnormalities) was performed.

Statistics:

Not applicable

Results and discussion

Preliminary study:

Not applicable

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 50 - < 300 mg/kg bw

Based on:

test mat.

Mortality:

300 mg/kg bw, first assay: Death occurred in 1/3 females 2 hours after treatment. Another female was found dead on day 13.
300 mg/kg bw, confirmatory assay: Death occurred in 1/3 animals on day 2.
50 mg/kg bw: No deaths in both the first and the confirmatory assay.

Clinical signs:

300 mg/kg bw, first assay: Hypoactivity then sedation, and dyspnea were observed prior to the death of the first female. Hypoactivity, piloerection, dyspnea, swollen abdomen, chromodacryorrhea, soft faeces and body weight loss were observed before the death of the second female. In the surviving animal, hypoactivity, dyspnea and rhinorrhea were noted between day 1 and day 3. Dyspnea persisted until day 6.
300 mg/kg bw, confirmatory assay: Hypoactivity, piloerection and dyspnea were noted prior the death of the first animal. In the surviving animals, hypoactivity, piloerection and dyspnea were observed on day 1 only.
50 mg/kg bw: No deaths in both the first and the confirmatory assay.

Body weight:

A body weight loss was noted between day 8 and day 15 in 1/3 surviving animals given 300 mg/kg in the fisrt assay.
When compared to CIT historical control animals, a slightly lower body weight gain was noted between day 1 and day 8, in 1/3 surviving females given 300 mg/kg and in 1/6 females given 50 mg/kg. Both body weight gains return to normal thereafter.
The body weight gain of the other animals was not affected by treatment with the test item.

Gross pathology:

Macroscopic examination of the main organs of the animals revealed no apparent abnormalities.

Other findings:

None

Any other information on results incl. tables

No other information

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category III

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the experimental conditions of this study, the oral LD50 of the test item was comprised between 50 and 300 mg/kg bw in rats.

Executive summary:

In an acute oral toxicity study, performed according to the test guidelines OECD No. 423 and EC 96/54, B.1 ter and in compliance with GLP, groups of fasted Sprague-Dawley female rats were administered a single oral dose of test substance in corn oil by gavage (dose volume 10 mL/kg bw). The animals were observed for mortality, clinical signs and body weight for 14 days and then necropsied for macroscopic observations.

 

Three animals were first given an oral dose of 300 mg/kg bw. Death occurred in 1/3 females 2 hours after treatment. Hypoactivity then sedation, and dyspnea were observed prior to its death. Another female was found dead on day 13. Hypoactivity, piloerection, dyspnea, swollen abdomen, chromodacryorrhea, soft faeces and body weight loss were observed. In the surviving animal, hypoactivity, dyspnea and rhinorrhea were noted between day 1 and day 3. Dyspnea persisted until day 6.When compared to historical control animals, a slightly lower body weight gain was noted in the surviving female between day 1 and day 8 (returning to normal thereafter).

Three animals were then given an oral dose of 300 mg/kg bw in a confirmatory assay. Death occurred in 1/3 animals on day 2. Hypoactivity, piloerection and dyspnea were noted prior to its death. In the surviving animals, hypoactivity, piloerection and dyspnea were observed on day 1 only. A body weight loss was noted in 1/2 surviving animals between day 8 and day 15. At necropsy, no apparent abnormalities were observed in any animal.

As mortality and clinical signs occurred at 300 mg/kg bw, a lower dose was tested. Two independent and successive groups of 3 female rats each were given the dose of 50 mg/kg bw. No deaths and no clinical signs were observed at this dose-level. When compared to historical control animals, a slightly lower body weight gain was noted in 1/6 females between day 1 and day 8 (returning to normal thereafter). The body weight gain of the other animals was not affected by treatment with the test item.At necropsy, no apparent abnormalities were observed in any animal.

 

The oral LD₅₀ of the test substance was comprised between 50 and 300 mg/kg bw in female rats.

 

Therefore under the test conditions, the substance is classified as Toxic if swallowed:

- Category 3 (H301) according to the criteria of the Regulation (EC) No. 1272/2008 (CLP)

- T; R25 according to the criteria of the Council Directive 67/548/EEC (and subsequent adaptations).

 

This study is considered as acceptable as it satisfied the criteria of OECD guidelines for the acute toxicity.