Benzonitrile

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1970

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1970

Report date:

1970

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

not specified

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Benzonitrile

EC Number:

202-855-7

EC Name:

Benzonitrile

Cas Number:

100-47-0

Molecular formula:

C7H5N

IUPAC Name:

benzonitrile

impurity 1

Reference substance name:

Toluene

EC Number:

203-625-9

EC Name:

Toluene

Cas Number:

108-88-3

Molecular formula:

C7H8

IUPAC Name:

toluene

impurity 2

Reference substance name:

Benzaldehyde

EC Number:

202-860-4

EC Name:

Benzaldehyde

Cas Number:

100-52-7

Molecular formula:

C7H6O

IUPAC Name:

benzaldehyde

impurity 3

Reference substance name:

Terephthalonitrile

EC Number:

210-783-2

EC Name:

Terephthalonitrile

Cas Number:

623-26-7

Molecular formula:

C8H4N2

IUPAC Name:

terephthalonitrile

impurity 4

Reference substance name:

Benzene-1,3-dicarbonitrile

EC Number:

210-933-7

EC Name:

Benzene-1,3-dicarbonitrile

Cas Number:

626-17-5

Molecular formula:

C8H4N2

IUPAC Name:

isophthalonitrile

impurity 5

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

water

Test material form:

liquid

Test animals

Species:

rat

Strain:

other: Charles River Albino (COBS)

Sex:

male/female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Doses:

ranging from 0.6 to 2.0 g/kg bw

No. of animals per sex per dose:

2 males and 2 females per dose

Control animals:

not specified

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

1 000 mg/kg bw

Mortality:

see "Other results incl Tables"

Any other information on results incl. tables

The acute oral median lethal dose (LD50) was calculated using the techniques of Weil (1952), Thompson (1947), and Thompson and Weil (1952).

 

Acute Oral Toxicity Study with Albino Rates – Mortality and Body Weight Data

 

Dose* (g/kg)	Animal Number and Sex	Individual Body Weights (grams) Test Day Number		Number Dead / Number Tested	Percent Dead
		0	14
0.6	1-M	252	342	0/4	0
	2-M	242	326
	3-F	183	234
	4-F	180	230
0.9	5-M	233	346	2/4	50
	6-M	220	(2 days)
	7-F	196	(3 days)
	8-F	178	243
1.4	9-M	176	283	3/4	75
	10-M	249	(6 days)
	11-F	194	(2 days)
	12-F	197	(2 days)
2.0	13-M	214	(3 days)	4/4	100
	14-M	221	(3 days)
	15-F	220	(3 days)
	16-F	184	(6-22 hours)
Note: Figures in parentheses indicate time of death * Benzonitrile ws administered undiluted. Acute Oral LD50 = 1.0 g/kg Standard Deviation of LD50 =±.2 g/kg

Summary of Reactions to the Acute Oral Toxicity Study of Albino Rats

Dose (g/kg)	Reaction	Time of Onset following Dose Administration (hours)	Duration of Reaction (days)	Time of Death Following Dose Administration (days)
0.6	Hyperactivity	6-22	2	-
	Muscular weakness	6-22	2
	Ruffed fur	6-22	2
0.9	Hyperactivity	1	3	2-3
	Muscular weakness	1	3
	Ruffed fur	6-22	2
	Prostration	6-22	2
1.4	Hyperactivity	1	4	2-6
	Muscular weakness	1	4
	Ruffed fur	6-22	4
	Prostration	6-22	2
2.0	Hyperactivity	1	Until death	6 hours–3 days
	Muscular weakness	1
	Ruffed fur	6-22
	Prostration	6-22
	Dyspnea	6-22
	Lacrimation	1 day

 

 

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category IV

Conclusions:

The acute oral median lethal dose (LD50) for oral application of benzonitrile on rats was determined at: LD50= 1.0 g/kg.

Executive summary:

In an acute oral toxicity study 4 groups (2 male + 2 female each) of young Albino rats (body weight ranged from 176 to 252 grams) were given a single oral dose of undiluted benzonitrile at doses of 0.6, 0.9, 1.4 and 2.0 g/kg bw.  Animals were then observed for 14 days.

Oral LD50 Combined = 1.0 g/kg  bw (Standard Deviation of LD50 =±0.2 g/kg)

Benzonitrile is of slight toxicity based on the combined LD50. According (EC) 1272/2008 benzonitrile is classified as acute toxic Category 4.