2-methylglutaronitrile

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

No data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study is comparable to OECD 401. It is well conducted but not GLP. The purity is not indicated.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not stated

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study is similar to the 402 OECD. The GLP are not stated. The purity is not indicated.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

: Occlusive conditions

Principles of method if other than guideline:

Not applicable

GLP compliance:

no

Remarks:

Study performed before GLP statement.

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: IFFA CREDO
- Age at study initiation: No data
- Weight at study initiation: 160-180g
- Fasting period before study: no data
- Housing: cage dimension 37.5 x 17 x 15 cm, 1 animal per cage
- Diet: IFFARAT, ad libitum
- Water: ad libitum
- Acclimation period: No data


ENVIRONMENTAL CONDITIONS
- Temperature: 22°C +/- 1°C
- Humidity: 50% +/- 10%
- Air changes: 8 per hr
- Photoperiod: No data


IN-LIFE DATES: No data

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: on the back
- % coverage: no data
- Type of wrap if used: aluminium and sparadrap


REMOVAL OF TEST SUBSTANCE
- Washing (if done): No


TEST MATERIAL
- Amount(s) applied: 1.05, 1.16, 1.58 and 2.11 ml/kg
- Constant volume or concentration used: no

Duration of exposure:

24 hours

Doses:

1000, 1100, 1500 and 2000 mg/kg bw

No. of animals per sex per dose:

5 animals/sex/dose for 1500 and 2000 mg/kg bw
10 animals/sex/dose for 1000 and 1100 mg/kg bw

Control animals:

yes, concurrent no treatment

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:         
Behaviour and mortality: immediately after exposure, then 1, 2 and 6h after exposure and then daily until day 14 
Body weight: at 0, 1, 2, 4, 7 and 14 after exposure
- Necropsy of survivors performed: yes

Statistics:

The LD50 was calculated by the method of Litchfield and  Wilcoxon

Preliminary study:

A preliminary study was conducted. Three groups (2M + 2F each) were exposed  in the same conditions (except the use of an aqueous dispersion of 10%  arabic gum as vehicle for 100 and 500 mg/kg bw) to 100, 500 and 1000 mg/kg of methylglutaronitrile,  and observed for 14 days. At 100 mg/kg, no mortality was observed. At 500 mg/kg, 2/2 males and 0/2 females died. At 1000 mg/kg, 1/2 males and 0/2 females died.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

1 154 mg/kg bw

95% CL:

>= 1 004 - <= 1 328

Key result

Sex:

male

Dose descriptor:

LD50

Effect level:

982 mg/kg bw

Remarks on result:

other: Not presented in the report but determined by our own calculation

Sex:

female

Dose descriptor:

LD50

Effect level:

1 403 mg/kg bw

Remarks on result:

other: Not presented in the report but determined by our own calculation

Mortality:

At equivalent dose level, mortality was more pronounced in males than in females. See detailed results in table 7.2.3/2

Clinical signs:

other: Reduced activity, apathy, prostration, slight ptosis,  slight tremor.

Gross pathology:

The autopsy of animals died during the test revealed:
- haemorrhagic lungs,
- pale and mottled liver,
- thickened peritoneum,
- hemorrhagic patch on the skin.
No macroscopic abnormalities were observed in the surviving animals.

Other findings:

No other fingings. No skin lesions.

Table 7.2.3/2: Number of animals dead

Dose (mg/kg bw)	Volume (mL/kg)	Mortality (# dead/total)			Time range of deaths
		Male	Female	Combined
0	-	0/5	0/5	0/10	-
1000	1.05	4/10	1/10	5/20	day1 (2M); days 3 +4 (3M), days 7 +14 (4M) day 1 -14 (1F)
1100	1.16	7/10	4/10	11/20	day 1(6 M), days 2 -14 (7M) day1 (1F), day 14(4F)
1500	1.58	5/5	3/5	8/10	day1 (4M), day2 (5M) day 1-14 (3F)
2000	2.11	5/5	4/5	9/10	day1 (4M), day2 (5M) day 1 (3 F), day2 -14 (4F)

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

Under the test conditions of this study, males were more sensitive than female rats. Therefore, based on the oral LD50 of male rats (= 982 mg/kg bw) considering as the worst case, 2-Methylglutaronitrile is considered in Category 3 (H311: Toxic in contact with skin) according to the Regulation 1272/2008 and as Harmful in contact with skin (Xn, R21) according to the Directive 67/548/EEC.

Executive summary:

In an acute dermal toxicity study performed similarly to the OECD test guideline No. 402, Sprague-Dawley rats were exposed to 2 -methylglutaronitrile undiluted for 24 hours at doses of 0, 1000, 1100, 1500 and 2000 mg/kg bw.  Animals then were observed for 14 days. Reduced activity, apathy, prostration, slight ptosis, slight tremor were observed in all treated animals.

Dermal LD₅₀ male/female = 1154 mg/kg bw

Dermal LD₅₀ male = 982 mg/kg bw

Dermal LD₅₀ female = 1403 mg/kg bw

At equivalent dose level, mortality was more pronounced in males than in females. Under the test conditions of this study, males were more sensitive than female rats. Therefore, based on the oral LD50 of male rats considering as the worst case, 2-Methylglutaronitrile is considered in Category 3 (H311: Toxic in contact with skin) according to the Regulation 1272/2008 and as Harmful in contact with skin (Xn, R21) according to the Directive 67/548/EEC.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

: Minor deviation: Age at study initiation is not mentionned.

GLP compliance:

no

Remarks:

study performed before GLP statement

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-methylglutaronitrile

EC Number:

224-923-5

EC Name:

2-methylglutaronitrile

Cas Number:

4553-62-2

Molecular formula:

C6H8N2

IUPAC Name:

2-methylpentanedinitrile

Constituent 2

Reference substance name:

methyl-2-glutaronitrile

IUPAC Name:

methyl-2-glutaronitrile

Details on test material:

- Name of test material (as cited in study report): Methylglutaronitrile Technique (MGN)
- Physical state: clear liquid

No other data are available

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: IFFA CREDO
- Age at study initiation: no data
- Weight at study initiation: 160-180g
- Fasting period before study: yes, approximately 17/19h before test  substance administration
- Housing: cage dimension 37.5 x 23.5 x 16 cm, 5 animals per cage
- Diet: IFFARAT, ad libitum
- Water: ad libitum
- Acclimation period: no data


ENVIRONMENTAL CONDITIONS
- Temperature: 22°C +/- 1°C
- Humidity: 50% +/- 10%
- Air changes: 8 per hr
- Photoperiod (hrs dark / hrs light): no data


IN-LIFE DATES: No data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: aqueous suspension of 10% arabic gum

Details on oral exposure:

VEHICLE
- Concentration in vehicle: no data
- Justification for choice of vehicle: No data
- Lot/batch no. (if required): No data
- Purity: No data

MAXIMUM DOSE VOLUME APPLIED: 8 mL/kg

- Rationale for the selection of the starting dose: A preliminary study was conducted. 5 groups (2M + 2F each) were exposed  to 100, 500, 1000, 2500 or 5000 mg/kg of MGN, and observed  for 14 days. 

Doses:

150, 200, 250, 300 and 400 mg/kg bw

No. of animals per sex per dose:

5 animals/sex/dose

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
   * Behaviour and mortality: immediatly after exposure, then 1, 2 and 6 h after exposure and then daily until day 14.
* Body weight: at 0, 1, 2, 4, 7 and 14 days after exposure
- Necropsy of survivors performed: yes

Statistics:

The LD50 was calculated by the method of Litchfield and  Wilcoxon

Results and discussion

Preliminary study:

100 % mortality was observed at 500 mg/kg bw and above.

Effect levels

Effect levels 1

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

205 mg/kg bw

95% CL:

>= 174 - <= 243

Effect levels 2

Sex:

male

Dose descriptor:

LD50

Effect level:

170 mg/kg bw

Remarks on result:

other: Not presented in the report but it is calculated

Effect levels 3

Sex:

female

Dose descriptor:

LD50

Effect level:

225 mg/kg bw

Remarks on result:

other: Not presented in the report but it is calculated

Mortality:

Males are more sensitive than females. See detailed results in table 7.2.1/2.
In Males:
- 20% mortality was observed at 150 mg/kg bw
- 80% mortality was observed at 200, 250 and 300 mg/kg bw
- 100 % mortality was observed at 400 mg/kg bw
In females:
- 0% mortality was observed at 150 mg/kg bw
- 20% mortality was observed at 200 mg/kg bw
- 40% mortality was observed at 250 mg/kg bw
- 100 % mortality was observed at 300 and 400 mg/kg bw

Clinical signs:

other: - At all doses tested (males and females): reduced activity, apathy, prostration, piloerection, trembling and convulsion were observed. These effects were reversible 24 hours after treatment.

Gross pathology:

- The autopsy of animals died during the test revealed haemorrhagic digestive tract, thymus and lungs.
- No macroscopic abnormalities were observed in the surviving animals.

Other findings:

No remarks

Any other information on results incl. tables

Table 7.2.1/2: Number of animals dead

 

Dose (mg/kg bw)	Mortality (# dead/total)			Time range of deaths
	Male	Female	Combined
0	0/5	0/5	0/10	-
150	2/5	0/5	2/10	day 1
200	4/5	1/5	5/10	2h (2 males), 6h (2 males), 6h (1 female)
250	4/5	2/5	6/10	6 h (1 male), 1 d (3 males), 1 d (2 female)
300	4/5	5/5	9/10	2 h (1 male), 6 h (3males), 6 h(2 females), d1 (3 females)
400	5/5	5/5	10/10	2h (3 males), 6h (2 males), 6 h (5 females)

Applicant's summary and conclusion

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

Under the test conditions of this study, males were more sensitive than female rats. Therefore, based on the oral LD50 of male rats considering as the worst case, 2-Methylglutaronitrile is considered in Category 3 (H301: Toxic if swallowed ) according to the Regulation 1272/2008 and as toxic if swallowed (T, R25) according to the Directive 67/548/EEC.

Executive summary:

In an acute oral toxicity study performed similarly to the OECD test guideline No. 401, groups of fasted Sprague-Dawley rat (5/sex/group) were given a single oral dose of 2- Methylglutaronitrile (2-MGN) in aqueous suspension of 10% arabic gum at doses of 0, 150, 200, 250, 300 or 400 mg/kg bw and observed for 14 days. At all doses tested (males and females), the clinical signs observed were reduced activity, apathy, prostration, piloerection, trembling and convulsion. All these signs were reversible 24 hours after the treatment. Haemorrhagic digestive tract, thymus and lungs was observed in the animals died during the study. The body weight and weight gain were not affected.

Oral LD₅₀male/female = 205 mg/kg bw

Oral LD₅₀male = 170 mg/kg bw

Oral LD₅₀ female = 225 mg/kg bw

Based on the oral LD50 of male rats considering as the worst case (more sensitive than female), 2-Methylglutaronitrile is considered in Category 3 (H301: toxic if swallowed) according to the Regulation 1272/2008/EC and as toxic if swallowed (T, R25) according to the Directive 67/548/EEC.