2-phenylhexanenitrile

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Between 10th January 1995 and 9th February 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.1 bis (Acute Oral Toxicity - Fixed Dose Procedure)

Deviations:

no

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-phenylhexanenitrile

EC Number:

423-460-8

EC Name:

2-phenylhexanenitrile

Cas Number:

3508-98-3

Molecular formula:

C12 H15 N

IUPAC Name:

2-phenylhexanenitrile

Test material form:

liquid

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

Equal numbers of healthy male and female CD rats of Sprague-Dawley origin (Hsd/Ola:SpragueDawley(CD)) were obtained from Harlan Olac Ltd. , Bicester, axon, England.
They were in the weight range of 92 to 126 g and approximately four to seven weeks of age prior to dosing (Day 1) in the main study. All the rats were acclimatised to the experimental environment for a minimum period of five days prior to the start of the main study.
The rats were allocated without conscious bias to cages within the treatment groups. They were housed in groups of up to five rats of the same sex in metal cages with wire mesh floors in Building R14 Room 6.
A standard laboratory rodent diet (Special Diet Services LAD 1) and drinking water were provided ad libitum. Access to food only was prevented overnight prior to and approximately 4 hours after dosing.
The batch(es) of diet used for the study was analysed for certain nutrients, possible contaminants and micro-organisms.
Results of routine physical and chemical examination of drinking water at source, as conducted. usually weekly by the supplier, are made available to Huntingdon Research Centre Ltd. (as quarterly summaries).
Animal room temperature was set to achieve a temperature of 22 ± 3°C. Relative humidity was not controlled but was anticipated to be in the range 30 - 70 % RH. Permanent daily recordings of these parameters were made and these are archived with other Department raw data. Any slight deviation in temperature and humidity that may have occurred was not considered to have affected the integrity or validity of the study. Air exchange was maintained at 10 to 15 air changes per hour and lighting controlled by means of a time switch to provide 12 hours of artificial light (0700 - 1900 hours) in each 24-hour period.
Each animal was identified by cage number and ear punching. Each cage was identified by a coloured label displaying the dose level, study schedule number, animal mark and the initials of the Study Director and Home Office licensee.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

The appropriate dose volume of the test substance was administered to each rat by oral gavage using a syringe and plastic catheter (8 choke).
The day of dosing was designated Day 1 .

Doses:

A preliminary study was carried out by dosing one female rat at 500 mg/kg bodyweight.

A group of ten rats (five males and five females) was treated at 2000 mg/kg bodyweight. Additional groups of ten rats (five males and five females) were similarly treated at 500 and 50 mg/kg bodyweight to further define the acute oral toxicity and establish the discriminating dosage of Salicynalva.

No. of animals per sex per dose:

A preliminary study was carried out by dosing one female rat at 500 mg/kg bodyweight.
A group of ten rats (five males and five females) was treated at 2000 mg/kg bodyweight.
Additional groups of ten rats (five males and five females) were similarly treated at 500 and 50 mg/kg bodyweight.

Control animals:

no

Details on study design:

TREATMENT PROCEDURE
Preliminary study
A preliminary study was carried out by dosing one female rat at 500 mg/kg bodyweight.

Main study
A group of ten rats (five males and five females) was treated at 2000 mg/kg bodyweight. Additional groups of ten rats (five males and five females) were similarly treated at 500 and 50 mg/kg bodyweight to further define the acute oral toxIcity and establish the LC50 of Salicynalva.

Control animal
No control animals were included in this study.

ADMINISTRATION OF TEST SUBSTANCE
The appropriate dose volume of the test substance was administered to each rat by oral gavage using a syringe and plastic catheter (8 choke).
The day of dosing was designated Day 1 .

OBSERVATIONS
- Mortality: Cages of rats were checked at least twice daily for any mortalities.
- Clinical signs: Animals were observed soon after dosing and at frequent intervals for the remainder of Day 1 (a minimum period of five hours). On subsequent days animals were observed once in the morning and again at the end of the experimental day (with the exception of Day 15 - morning only). This latter observation was at approximately 16:30 hours on week days or 11:30 hours on Saturdays and Sundays. The nature and severity of the clinical signs and time were recorded at each observation.
The animals in the preliminary study and those surviving treatment in the main study were observed for 7 and 14 days respectively after dosing.
- Bodyweight: The bodyweight of each rat in the main study was recorded on Days 1 (prior to dosing), 2, 3, 4, 8 and 15 or at death. Individual weekly bodyweight change and group mean body weight data were calculated.

TERMINAL STUDIES
- Termination: All surviving animals on the main study were killed on Day 15 by cervical dislocation.
- Macroscopic pathology: All animals were subjected to a macroscopic examination which consisted of opening the abdominal and thoracic cavities. The macroscopic appearance of all tissues was recorded.

Results and discussion

Preliminary study:

A preliminary study was carried out by dosing one female rat at 500 mg/kg bodyweight. This dosage was selected to give an initial indication of test substance toxicity. A minimal systemic response to treatment (piloerection only) was seen within five minutes of dosing.
There were no other clinical signs and recovery was complete by Day 7. This animal achieved a satisfactory bodyweight gain for a study of this duration.
Macroscopic examination on Day 8 revealed a thickening of the glandular region of the stomach but otherwise no abnormalities were observed.

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

One male at 500 mg/kg and two males and two females at 2000 mg/kg died during the study. All deaths occurred between 24 and 48 hours of dosing.

Clinical signs:

other: Piloerection was observed in all rats within five minutes of dosing and persisted in the majority of animals throughout the remainder of Day 1. This sign was accompanied on Day 1 and/or at later intervals by abnormal body carriage (hunched posture) in all

Gross pathology:

Macroscopic examination of decedents revealed:

Male - 500 mg/kg
Congestion (characterised by dark tissue) in the lungs, liver, spleen and kidneys. In addition, congestion (characterised by dark tissue and fluid contents) was seen in the stomach and small intestine.

Males and females - 2000 mg/kg
Congestion (characterised by dark tissue) in the thymus, heart, lungs, liver and kidneys with splenic pallor and atrophy. In addition, congestion (identified by gaseous distension, fluid contents, thinning/thickening/bleaching and prominent blood vessels) was seen in the stomach and along the alimentary tract.

No macroscopic abnormalities were observed for animals killed on Day 15.

Applicant's summary and conclusion

Interpretation of results:

other: not harmful in accordance with EU CLP (EC no 1272/2008 and its amendments)

Conclusions:

The substance has an LD50 of > 2000 mg/kg bw in an OECD TG 420 test

Executive summary:

A study was performed to assess the acute oral toxicity of Salicynalva to the rat according to the fixed dose procedure, similar to OECD TG 420. Groups of ten fasted rats (five males and five females) were given a single dose by oral gavage of the test substance, as supplied, at dosages of 500 and 2000 mg/kg bodyweight. A further group was treated using the test substance formulated in distilled water at a dosage of 50 mg/kg body weight. All animals surviving treatment were killed and examined macroscopically on Day 15, the end of the observation period. One male at 500 mg/kg and two males and two females at 2000 mg/kg died during the study. All deaths occurred between 24 and 48 hours of dosing. A slight body weight loss was recorded for some decedents. Macroscopic examination revealed congestion in the majority of major organs and tissues. Clinical signs of reaction to treatment were confined to piloerection in rats dosed at 50 mg/kg. Among rats treated at 500 and 2000 mg/kg, piloerection, abnormal body carriage, abnormal gait, decreased respiratory rate, pallor of the extremities, increased salivation, walking on toes and unsteadiness were observed. In addition, lethargy, increased urine production and hair loss were evident among rats dosed at 2000 mg/kg only. Recovery of surviving rats was complete in all instances by Day 9 with the exception of hair loss which had resolved in the majority of surviving rats dosed at 2000 mg/kg by Day 10 or Day 11 but persisted in one surviving rat dosed at 2000 mg/kg through to the end of the observation period (Day 15). Slightly low body weight gains were recorded on Day 8 for three males and one female dosed at 2000 mg/kg bodyweight; these animals achieved the anticipated bodyweight gains on Day 15. All other surviving animals achieved satisfactory bodyweight gains throughout the study. No abnormalities were recorded at the macroscopic examination on Day 15. The LD50 of Salicynalva when administered orally to rats was established to be > 2000 mg/kg bodyweight.