4,4'-methylenebis(2,6-xylidine)

Endpoint summary

Description of key information

Acute toxicity, oral in rats: 300 mg/kg bw < LD50 < 2000 mg/kg bw (OECD 423, GLP, K, Rel. 1)

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

08 August - 31 August 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

dated 17 December, 2001

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

27 April 2017

Test type:

acute toxic class method

Limit test:

no

Specific details on test material used for the study:

• Sponsor’s identification: 4,4'-méthylène bis (2,6-diméthylaniline)
• Synonym: DURCISSEUR DX
• Chemical name: 4-[(4-amino-3,5-dimethylphenyl)methyl]-2,6-dimethylaniline

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 160 209 0004 (Lot Isochem)
- Expiration date of the lot/batch: 01 October 2018

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

Species:

rat

Strain:

Sprague-Dawley

Remarks:

SPF Caw

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Elevage JANVIER LABS (53940 Le Genest St Isle – France)
- Females (if applicable) nulliparous and non-pregnant: Yes
- Age at study initiation: 8 weeks
- Weight at study initiation: 193-207 g
- Fasting period before study: Food was removed on Day 1 and then redistributed 4 hours after the test item administration.
- Housing: Animals were housed by group of three in solid-bottomed clear polycarbonate cages with a stainless steel mesh lid.
- Diet (e.g. ad libitum): Foodstuff (ENVIGO - 2016), ad libitum
- Water (e.g. ad libitum): Drinking water (tap-water from public distribution system), ad libitum
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 19-25°C
- Humidity: 30-70%
- Air changes: At least 10/hour
- Photoperiod: 12 hours dark / 12 hours light

Route of administration:

oral: gavage

Vehicle:

DMSO

Details on oral exposure:

DOSAGE PREPARATION: In the first and second steps of the study, 0.3024 g and 0.3031 g of the test item were weighed and distilled water was added to two 10 mL volumetric flasks. The preparations were stirred by vortex to obtain yellow solutions just before the administration.
In the third and fourth steps of the study, 2.0002 g and 2.0006 g of the test item were weighed and distilled water was added to two 10 mL volumetric flasks. The preparations were stirred by vortex to obtain yellow solutions just before the administration.
The preparations were administered under a volume of 10 mL/kg body weight using a suitable graduated syringe fitted with an oesophageal metal canula.

Doses:

300 and 2000 mg/kg bw

No. of animals per sex per dose:

6 female rats

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical observations and mortality were recorded at 30 minutes, 1 hour, 3 hours, 4 hours, 24h, 48h after administration of the test item and continued daily during 14 days. Animals were weighed on Day 0 (just before administering the test item) and then on Day 2, Day 7 and Day 14.
- Necropsy of survivors performed: Yes; animals were euthanized with sodium pentobarbital on Day 14 and macroscopic observations were noted.

Statistics:

No data

Preliminary study:

Not applicable

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - < 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was noted in the animals treated at the dose of 300 mg/kg body weight. During the step 3, three mortalities were noted in the animals treated at the dose of 2000 mg/kg body weight on day 10.
During the step 4, no clinical signs and no mortality related to the administration of the test item were observed in the three animals

Clinical signs:

No clinical signs related to the administration of the test item were observed at the dose of 300 mg/kg body weight.
It was only noted an increase of salivation (1/3) at 30 minutes post-dose. Then, between days 8 and 9, an absence of spontaneous activity (3/3), righting reflex (3/3), Preyer’s reflex (3/3) and muscle tone (3/3), hypothermia (3/3), lachrymation (3/3), piloerection (2/3) and eyes partly closed (2/3) were noted at the dose of 2000 mg/kg body weight.

Body weight:

The body weight evolution of the animals remained normal during the study.

Gross pathology:

The macroscopic examination of the animals at the end of the study did not reveal treatment related changes.

Other findings:

None

None

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Under the test conditions, the oral LD50 of the test substance is higher than 300 mg/kg body weight and lower than 2000 mg/kg body weight by oral route in the rat. In accordance with the O.E.C.D. Test Guideline No. 423, the LD50 cut-off of the test item may be considered as 500 mg/kg body weight by oral route in the rat. According to the criteria for classification, packaging and labelling of dangerous substances and preparations in accordance with the Regulation EC No. 1272/2008, the test item 4,4'-méthylène bis
(2,6-diméthylaniline) has to be classified in category 4. The signal word “Warning” and hazard statement H302 “Harmful if swallowed” are required

Executive summary:

In an acute oral toxicity study performed according to the OECD Guideline 423 and in compliance with GLP, the test item 4,4'-méthylène bis (2,6-diméthylaniline) in DMSO was administered by oral gavaget o a group of 6 female Sprague Dawley rats at the dose of 300 mg/kg body weight and then to a group of 6 female Sprague Dawley rats at the dose of 2000 mg/kg body weight.

Animals were then observed for mortality and clinical signs of toxicity for 14 days.

No mortality was noted in the animals treated at the dose of 300 mg/kg body weight. No clinical signs related to the administration of the test item were observed during the study. The body weight evolution of the animals remained normal during the study. The macroscopic examination of the animals at the end of the study did not reveal treatment related changes. During the step 3, three mortalities were noted in the animals treated at the dose of 2000 mg/kg body weight on day 10. It was only noted an increase of salivation (1/3) at 30 minutes post-dose. Then, between days 8 and 9, an absence of spontaneous activity (3/3), righting reflex (3/3), Preyer’s reflex (3/3) and muscle tone (3/3), hypothermia (3/3), lachrymation (3/3), piloerection (2/3) and eyes partly closed (2/3) were noted. Decrease of body weight (-10.1%) was noted in these 3 animals at day 7 versus day 2. Rigor mortis was noted before the necropsy. The macroscopic examination of these 3 animals did not reveal treatment related changes. During the step 4, no clinical signs and no mortality related to the administration of the test item were observed in the three animals.

The body weight evolution of the animals remained normal during the study. The macroscopic examination of the animals at the end of the study did not reveal any treatment related changes.

Under the test conditions, the oral LD50 of the test substance is higher than 300 mg/ kg body weight and lower than 2000 mg/ kg body weight by oral route in the rat.

In accordance with OECD Guideline 423, the LD50 cut-off of the test substance may be considered as 500 mg/ kg body weight by oral route in the rat. Therefore, according to the criteria for classification, packaging and labelling of dangerous substances and preparations in accordance with the Regulation EC No. 1272/2008, the test item 4,4'-méthylène bis (2,6-diméthylaniline) has to be classified in category 4. The signal word “Warning” and hazard statement H302 “Harmful if swallowed” are required.

.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

500 mg/kg bw

Quality of whole database:

Guideline GLP study

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Acute toxicity: via oral route

In an acute oral toxicity study performed according to the OECD Guideline 423 and in compliance with GLP, the test item 4,4'-méthylène bis (2,6-diméthylaniline) in DMSO was administered by oral gavaget o a group of 6 female Sprague Dawley rats at the dose of 300 mg/kg body weight and then to a group of 6 female Sprague Dawley rats at the dose of 2000 mg/kg body weight.

Animals were then observed for mortality and clinical signs of toxicity for 14 days.

No mortality was noted in the animals treated at the dose of 300 mg/kg body weight. No clinical signs related to the administration of the test item were observed during the study. The body weight evolution of the animals remained normal during the study. The macroscopic examination of the animals at the end of the study did not reveal treatment related changes. During the step 3, three mortalities were noted in the animals treated at the dose of 2000 mg/kg body weight on day 10. It was only noted an increase of salivation (1/3) at 30 minutes post-dose. Then, between days 8 and 9, an absence of spontaneous activity (3/3), righting reflex (3/3), Preyer’s reflex (3/3) and muscle tone (3/3), hypothermia (3/3), lachrymation (3/3), piloerection (2/3) and eyes partly closed (2/3) were noted. Decrease of body weight (-10.1%) was noted in these 3 animals at day 7 versus day 2. Rigor mortis was noted before the necropsy. The macroscopic examination of these 3 animals did not reveal treatment related changes. During the step 4, no clinical signs and no mortality related to the administration of the test item were observed in the three animals.

The body weight evolution of the animals remained normal during the study. The macroscopic examination of the animals at the end of the study did not reveal any treatment related changes.

Under the test conditions, the oral LD50 of the test substance is higher than 300 mg/ kg body weight and lower than 2000 mg/ kg body weight by oral route in the rat.

In accordance with OECD Guideline 423, the LD50 cut-off of the test substance may be considered as 500 mg/ kg body weight by oral route in the rat. Therefore, according to the criteria for classification, packaging and labelling of dangerous substances and preparations in accordance with the Regulation EC No. 1272/2008, the test item 4,4'-méthylène bis (2,6-diméthylaniline) has to be classified in category 4. The signal word “Warning” and hazard statement H302 “Harmful if swallowed” are required.

Justification for classification or non-classification

Harmonized classification:

The registered substance has no harmonized classification according to the Regulation (EC) No. 1272/2008.

Self-classification:

Acute toxicity via Oral route:

Based on the available information, the registered substance is:

- classified in category 4. The signal word “Warning” and hazard statement H302 “Harmful if swallowed” are required according to the Regulation (EC) No. 1272/2008 and GHS.

In a conservative approach, the substance was decided to be classified in the same category as acute oral toxicity for acute dermal toxicity and acute toxicity by inhalation (H312 and H332, respectively) according to the Regulation (EC) No. 1272/2008 and GHS.