3-methyl-5-phenylpent-2-enenitrile

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-03-16 to 2015-03-31

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Version / remarks:

2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3-methyl-5-phenylpent-2-enenitrile

EC Number:

299-682-2

EC Name:

3-methyl-5-phenylpent-2-enenitrile

Cas Number:

93893-89-1

Molecular formula:

C12 H13 N

IUPAC Name:

(2E)-3-methyl-5-phenylpent-2-enenitrile

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 10-11 weeks
- Weight at study initiation: Males: 253.4 to 298.6 g, Females: 191.1 to 218.6 g
- Fasting period: during study
- Housing: individually, standard polysulfone cages (Size: approximately L 425 x B 266 x H 185 mm),
- Diet: ad libitum, Teklad Certified (2014C) Global 14 % Protein Rodent Maintenance Diet -Pellet (Certified) manufactured by Harlan Laboratories B.V. AN Venray, The Netherlands
- Water: ad libitum, deep bore-well water passedc through charcoal filter an exposed to UV rays
- Acclimation period: 6-7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-24
- Humidity (%): 65-67
- Air changes (per hr): 12-15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose only

Vehicle:

clean air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: nose only exposure chamber
- Exposure chamber volume: 53 L
- Method of holding animals in test chamber: restrainers, polycarbonate tubes having facility to trap the faeces for individual exposure tubes, sizes males: length 19.0 cm, diameter 6.0 cm, females: length 15.0 cm, diameter 6.0 cm
- Source and rate of air: Dehumidified and filtered air from air compressor, 20 L/min
- Method of conditioning air: injection (0.2, 0.4 and 0.8 mL/min) and atomizing (Atomizer pressure 1.4 kg/cm2)
- System of generating particulates/aerosols: A glass atomizer was used. Manufactured by: Sai Scientifics Bengaluru Specification: Injection capacity of 1.6 mL/minute.
- Method of particle size determination: Instrument: GALAI CIS-50 particle size analyzer, Manufactured by: Galai Pvt. Ltd., Israel, Principle of measurement: Laser based 'Time-of-Transition Theory', Unit of measurement: Aerosol particle size in µm
- Treatment of exhaust air: collected in aerosol exhaust chamber and via filters to the exhaust system
- Temperature, humidity in air chamber: inner chamber: 22.9-25.3 °C, 73.4-77.5 % relative humidity, outer chamber: 19.9-26.8 °C, 64.9-78.3 % relative humidity

TEST ATMOSPHERE
- Brief description of analytical method used: during exposure areosol particle size, oxygen content in chamber air,
- Samples taken from breathing zone: yes
- Mean aerosol particle size: 0.2 mL/min: 1.79 ± 0.97 µm, 0.4 mL/min: 1.83 ± 0.97 µm, 0.8 mL/min: 1.73 ± 1.00 µm
- Geometric standard deviation (GSD): 0.2 mL/min: 1.99, 0.4 mL/min: 1.99, 0.8 mL/min: 2.19

A preliminary test with 6 (3M/3F) animals was performed to select the concentration for the main test. The concentration tested was 0.4 mL/min.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

test item injection rate was 0.2, 0.4 and 0.8 mL/min
average concentration: 0.2 mL/min = 3.31 mg/L, 0.4 mL/min = 9.23 mg/L, 0.8 mL/min = 10 mg/L

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observation: during exposure 1/h, directly after and 1 h after exposure, once daily from day 2-15, body weight: during acclimatisation, pre-exposure (day 1) and on day 2, 4, 8 and 15
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

No statistical analysis was performed.

Results and discussion

Preliminary study:

A preliminary test with 6 (3m/3f) animals was performed to select the concentration for the main test. The concentration tested was 0.4 mL/min. Animals showed Clear nasal discharge, slight salivation and moderate ataxia on day 1. Hypoactivity, arched back, slight /moderate ataxia and convulsions were observed. One female rat died on day 3.

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

5.31 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Mortality:

0.2 mL/min: no mortality during exposure, 3 male and 1 female died on day 2
0.4 mL/min: no mortality during exposure, 3 male and 1 female died on day 2, 2 females died on day 3
0.8 mL/min: no mortality during exposure, 3 male and 3 females died on day 2, 2 females died on day 3, 1 male died on day 4

Clinical signs:

other: 0.2 mL/min: clear nasal discharge, hypoactivity, slight tremors, slight salivation, slight/severe ataxia and slight piloerection; From day 4/5/6/7 onwards no clinical signs were observed. 0.4 mL/min: clear nasal discharge, hypoactivity, slight tremors, sl

Body weight:

0.2 mL/min: day 2 all decrease, day 4 decrease (one increase), day 8 decrease (three increase), day 15 all increase
0.4 mL/min: days 2, 4 and 8 all decrease, day 15 all increase
0.8 mL/min: 1 surviving rat: decrease on day 2, 4 and 8, increase on day 15
All animals that died during the observation time had a decreased body weight compared to the weight before exposure.

Gross pathology:

0.2 mL/min: In one preterminally dead male lung congestion was observed. All other animals showed no abnormalities.
0.4 mL/min: In two preterminally dead male and 1 female lung congestion was observed. All other animals showed no abnormalities.
0.8 mL/min: In three preterminally dead male and three female lung congestion was observed. All other animals showed no abnormalities.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The acute inhalation LD50 of the test substances aerosol was established to be 5.31 mg/L in rats.

Executive summary:

The acute inhalation toxicity of the test substance was investigated according to OECD Guideline 403 in rats. Experiments were conducted using GLP. In each case 10 animals were exposed for 4 h to an aerosol of test substance at concentrations of 3.31 mg/L (0.2 mL/min), 9.23 mg/L (0.4 mL/min) and 10 mg/L (0.8 mL/min). The animals were observed for 14 days after treatment. Animals exposed to 3.31 mg/L showed clear nasal discharge, hypoactivity, slight tremors, slight salivation, slight/severe ataxia and slight piloerection. 4 animals died on the day after exposure while the surviving animals recovered and no clinical signs were observed from day 7 onwards. Animals exposed to 9.23 and 10 mg/L showed clear nasal discharge, hypoactivity, slight tremors, slight/moderate salivation, slight/severe ataxia and slight piloerection. After exposure to 9.23 mg/L 6 animals died within the first 2 days and 9 animals died within the first 3 days after exposure to 10 mg/L. The surviving animals recovered and showed no clinical signs after day 8/9 after exposure. In all animals a decrease in body weight was detected after exposure. The surviving animals showed an increase in body weight 14 days after exposure. The acute inhalation LD50 for rats was established to be 5.31 mg/L aerosol. Therefore the test substance is not classified.