Benzonitrile

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1980

Report date:

1980

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: 40 CFR Part 163.81-2

Principles of method if other than guideline:

EPA, Pesticides Programs, proposed guidelines for registering pesticides in the U.S., hazard evaluation: humans and domestic animals

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:

rabbit

Strain:

New Zealand White

Sex:

male/female

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Duration of exposure:

24 hours

Doses:

2.0 g/kg, and thereafter 0.01, 0.05, 0.1, 0.5, and 1.0 g/kg,

No. of animals per sex per dose:

1 male + 1 female for range finding and 4 male + 4 female for LD50 determination

Control animals:

yes

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

1 400 mg/kg bw

Based on:

test mat.

95% CL:

1 - 1.8

Any other information on results incl. tables

Preliminary Range Finding Study:

Dose	Mortality
(g/kg)
0.01	0/2
0.05	0/2
0.1	0/2
0.5	0/2
1.0	0/2

 

Dose level, mortality data and LD₅₀calculations:

	Dose Level	Mortality
	(g/kg)	Male	Female	Abraded Skin	Intact Skin	Total
Mortality	0.5	0/4	0/4	0/4	0/4	0/8
	0.7	0/4	1/4	0/4	1/4	1/8
	1.0	0/4	2/4	1/4	1/4	2/8
	1.4	1/4	3/4	1/4	3/4	4/8
	2.0	3/5	5/5	8/10	0/0	8/10
	Control	(0/4)	(0/4)	(0/4)	(0/4)	(0/4)
LD50		1.8	1.0	1.55	1.05	1.4
95% Confidence Limit		1.2 to 2.4	0.6 to 1.4	1.15 to 1.95	0.65 to 1.45	1.0 to 1.8

 

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category IV

Conclusions:

The LD50 was calculated at 1.4 g/kg.

Executive summary:

In an acute dermal toxicity study, groups of 4 young adults New Zealand White rabbits/sex/dose were dermally exposed to Benzonitril (100 % a.i) for 24 hours to 10% of body surface area at doses of 0.5, 0.7, 1.0, 1.4 and 2.0 g/kg bw. Animals then were observed for 14 days.

 

Dermal LD₅₀:

      Males =1.8 g/kg bw (95% C.I. 1.2 to 2.4 g/kg bw)

      Females = 1.0 g/kg bw (95% C.I. 0.6 to 1.4 g/kg bw.)

      Combined = 1.4 g/kg bw (95% C.I. 1.0 to 1.8 g/kg bw.)