Indene

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 August 2005 - 08 September 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

17 December 2001

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: Study Methods on New Chemical Substances, etc.

Version / remarks:

November 21, 2003; YakuShokuHatsu; No. 1121002, Heisei 15-11-13 SeiKyoku No. 2, and KanHoKiHatsu No. 031121002, Revised on April 30, 2004

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Indene

EC Number:

202-393-6

EC Name:

Indene

Cas Number:

95-13-6

Molecular formula:

C9H8

IUPAC Name:

indene

Test material form:

liquid

Details on test material:

Appearance: Light yellow or colorless clear liquid
Storage: In refrigerator (2 - 8 °C)

Test animals

Species:

rat

Strain:

Sprague-Dawley

Remarks:

SPF [Crl:CD(SD)]

Sex:

female

Details on test animals or test system and environmental conditions:

- Source: Atsugi Breeding Center, Charles River Laboratories Japan, Inc.
- Age at study initiation: 6 weeks old
- Weight at study initiation: 127 to 139 g
- Fasting period before study: Overnight
- Housing: Animals were placed individually in bracket-type metallic wire cages
- Diet: Free access to pelleted diet CRF-I (radiation-sterilized: Oriental Yeast Co., Ltd)
- Water: Free access to tap water.
- Acclimation period: at least one week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 -25
- Humidity (%): 40 -59
- Air changes (per hr): 10 to 15
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From: 22 August 2005 to 8 September 2005

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

GAVAGE METHOD: A stomach tube.

Frequency: single dosage, on day 1.

VEHICLE
- Justification for choice of vehicle: The vehicle was selected based on trial formulations and stability tests performed in the lab.

MAXIMUM DOSE VOLUME APPLIED:
10 mL/kg body weight.


DOSAGE PREPARATION:

A requisite amount of the test article was weighed, put into corn oil and diluted to the specified concentration (200 mg/mL). The test formulations were prepared on day 4 before the first stage and on day 7 before the second stage. After preparation, they were put into brown glass bottles (light-resistant bottles) and preserved.

CLASS METHOD
- Rationale for the selection of the starting dose: Since it was estimated that the acute oral toxicity of the test article was extremely weak, the starting dose level was set at 2000 mg/kg bodyweight. The dose levels there after were selected based on the test procedure shown in the Toxicity Study Guidelines "Acute Toxic Class Method". Since no animal died after administration in the first dose stage, the dose level was set at 2000 mg/kg bodyweight also for the second dose step.

Doses:

2000 mg/kg body weight.
.

No. of animals per sex per dose:

6 (2 groups of three females in a stepwise manner)

Control animals:

no

Details on study design:

STUDY DESIGN:

Animals were deprived of food ca. 16 hours prior to dosing and 6 hours after administration of the test substance. Water and food was available ad libitum.

- Duration of observation period following administration: 14 days
- Frequency of observations: \frequently up to 6 hours after administration (immediately after, 5 minutes, 15 minutes, 30 minutes, 1 hour, 2 hours, 4 hours and 6 hours), and once daily for 14 days.
Body weights: Animals were weighed on the day of administration (before administration), and on days 1, 3, 7 and 14 after administration.
Clinical signs and mortality: At periodic intervals on the day of dosing (day 1) and once daily thereafter, until day 15.
- Necropsy of survivors performed: The animal found dead was subjected to pathological examination immediately. The surviving animals were euthanized by exsanguination (via the abdominal aorta under anesthesia after the end of the 14-day observation period, and subjected to macroscopic observation of the appearance the organs/tissues in the cervical, thoracic and abdominal regions.
- Other examinations performed: none.

Statistics:

No statistical analysis was performed

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No deaths occurred in the first dose group, but 1/3 animals died in the second dose group at day 2.

Clinical signs:

Lacrimation, salivation and ptosis were observed 1 hour after administration, and lacrimation, ptosis, abnormal gait and stained area around the nose/oral cavity was observed continuously 2 to 6 hours after administration. On day 1, the clinical signs observed were only ptosis and stained area around the nose/oral cavity. These clinical signs were no longer observed on day 2. There were no further abnormalities in the animals.

The animal that died showed lacrimation, salivation and ptosis 1 hour post administration, and lacrimation, ptosis, abnormal gait and staining around the nose/oral cavity continuously 2 to 6 hours post administration. On day 2, the animal showed prone/lateral position, decreased respiration rate, hypothermia, ptosis and stained nose/oral cavity and died in the afternoon.

Body weight:

The animals showed body weight decrease the day after administration, but the body weight increased again in the following days (day 3 and after). There were no additional abnormalities in body weight development of any animal.

Gross pathology:

There were no abnormalities found in the surviving animals.
The animal that died showed staining in the area around the nose/oral cavity, dark red foci in the lungs and whitening of the small intestines (from jejunum to ileum).

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In an acute oral toxicity study with rats, performed according to OECD test guideline 423 and GLP principles, an LD50 >2000 mg/kg bw was determined.

Executive summary:

An assessment of acute oral toxicity of indene in rats was performed according to OECD test guideline 423 and GLP principles. The test item was administered in corn oil by oral gavage to two groups of three female Sprague Dawley rats at 2000 mg/kg body weight. One animal died in the afternoon of day 2. The animal that died showed lacrimation, salivation and ptosis 1 hour post administration, and lacrimation, ptosis, abnormal gait and staining around the nose/oral cavity continuously 2 to 6 hours post administration. On day 2, the animal showed prone/lateral position, decreased respiration rate, hypothermia, ptosis and stained nose/oral cavity. Necropsy showed that there was staining around the nose/oral cavity, dark red foci in the lungs and whitening of the small intestines (from jejunum to ileum). In the surviving animals, lacrimation, salivation and ptosis were observed 1 hour post administration. Lacrimation, ptosis, abnormal gait and stained area around the nose/oral cavity were observed 2 to 6 hours post administration. On day 2, the clinical signs observed were only ptosis and stained area around the nose/oral cavity. These clinical signs were no longer observed on day 2. Body weight decreased initially but returned to normal after day 3. At necrosopy no abnormalities were found. An LD50 >2000 mg/kg body weight was determined. According to GHS regulations inderimne does not need to be classified for oral toxicity.