5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1996-06

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

Qualifier:

according to guideline

Guideline:

other: EPA Standard Evaluation Procedure: Inhalation Toxicity Testing

Version / remarks:

(Gross and Vocci)

Deviations:

no

GLP compliance:

yes

Test type:

fixed concentration procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

421-300-1

EC Name:

-

Cas Number:

138564-59-7

Molecular formula:

C12H9N3O2S

IUPAC Name:

5-methyl-2-[(2-nitrophenyl)amino]thiophene-3-carbonitrile

Test material form:

solid: particulate/powder

Details on test material:

97.7%
Item code QA405K
Lilly lot no: 356MO1

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Sponsor and 356M01
- Purity test date: 1995-11-10

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature in the dark

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test article was micro milled to aid aerosol generation
- Final preparation of a solid: The test aerosolwas generated by a Wright Dust Feeder II.The material was then passed through a cyclone designed to select particles <= 2µm MMEAD (Smith et al.1979). Air flow through the generator was continuously monitored using a Sierra Side-Trak (SierraIntruments, Carmel Valley,CA) and was maintained at a range of 14.5 to 15 Umin over the 4-hour exposure period

FORM AS APPLIED IN THE TEST (if different from that of starting material)
As a small particle aerosol to be inahled via compressed air.

Test animals

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Sprague Dawley, Cumberland, IN
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 9-10 weeks and 8-9 weeks for males and females repectively.
- Weight at study initiation: 233 +-12g and 154 +-4g for males and femlaes respectively.
- Fasting period before study:
- Housing: 5 per cage, with each cage being stainless steel ventilated with wire flors and Lexan fronts. 2 / cage following exposure.
- Diet (e.g. ad libitum): Purina Certified Rodent Chow 5002 ad libitum
- Water (e.g. ad libitum): Greenfield city water ad libitum
- Acclimation period: >7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.3-23.7
- Humidity (%): 20-80
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose only

Vehicle:

clean air

Mass median aerodynamic diameter (MMAD):

2.31 µm

Geometric standard deviation (GSD):

2.68

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Cannon 52 Port Flow-Past exposure chamber
- Method of holding animals in test chamber: Restrained with nose tubes
- Source and rate of air: Sierra Side Trak and 14.5-15 L/min
- Method of conditioning air: Dired and filtered by the appropiate equipment
- System of generating particulates/aerosols: Micromilling by a Wright Dust Feeder II
- Method of particle size determination: Use of a cyclone designed to select particles <=2 um MMEAD
- Treatment of exhaust air: None
- Temperature, humidity, pressure in air chamber: Monitored continuously during the exposure using a Neotronics Oxygen Monitor (Gainesville, GA) and a General Eastern Temperature and %RH monitor

TEST ATMOSPHERE
- Brief description of analytical method used: Total gravimetric basis based on samples taken during the exposure from a minimum of 8 samples each of 1 minute duration.
- Samples taken from breathing zone: yes

TEST ATMOSPHERE (if not tabulated)
- Particle size distribution:
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.):

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration:

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

ca. 4 h

Concentrations:

Nominal: 18 mg/L
Measured: 2.09 +- 0.36 (Mean +- SD) mg test substance/L of air

No. of animals per sex per dose:

10

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Immediately following exposure and 1, 3, 5, 7, and 14 days post exposure
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs

Statistics:

None

Results and discussion

Preliminary study:

A preliminary study identified the max possible concentration of the test substance in air while obtaining a MMEAD <4 um was the maximum tested concentration of 2.09 g/L

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LC50

Remarks on result:

not determinable due to absence of adverse toxic effects

Mortality:

1 male rat died of unrelated urinary tract issues.

Clinical signs:

other: Clinical observations in female rats were hypoactivity, soiling, yellow material on nose and face,yellow staining on face, orange liquid in cage pans, orange staining around inguinal region, and yellow-orange staining on underside of bodies. No mortality

Body weight:

Mean body weight for surviving animals exceeded preexposure levels upon termination of the live phase. Mean body weight gain values for surviving males and females were 21 ± 4 g (mean ± SD) and 11 ± 4 g, respectively.

Gross pathology:

One male died during the 14-day observation period with chronic lesions involving the urinary system. These were judged to be of spontaneous nature unrelated to treatment. All other animals were necropsied at the end of the live phase. No lesions were observed except for soiling of inguinal fur from deposition of compound during the exposure period in one male and all females.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

This study validly found that the test substance should not be classified, according to GHS criteria.

Executive summary:

The study was carried out in accordance with EPA Standard Evaluation Procedure: Inhalation Toxicity Testing (Gross & Vocci). It was conducted to determine the inhalation hazard resulting from exposure of rats for 4 hours to a dry powder aerosol of the test compound. Ten female and 10 male Fischer 244 rats were exposed to an aerosol of compound 290437 at a mean exposure concentration of 2.09mg/l of air. This was the highest exposure level that could be achieved while holding the mass medium equivalent aerodynamic diameter (MMEAD) below 4um. The MMEAD was 2.31um with a geometric standard deviation of 2.68.

No mortality was observed except for one male rat that died from spontaneous urinary system complications, unrelated to treatment. The gross pathologic examination revealed no detectable abnormalities except for soiling of inguinal fur from deposition of compound during the exposure period in one male and all females.

The 4 hour median lethal concentration was >2.09mg compound 290437/l of air and the classification of toxicity is in the lowest hazard category.