N,N'-(methylenedi-p-phenylene)bis[hexahydro-2-oxo-1H-azepine-1-carboxamide]

Endpoint summary

Description of key information

In two acute toxicity studies (limit test, rat) by oral and inhalation of dust exposure, no mortality was observed.

Finding were LC50(rat, inhalation): > 5070 mg/m³; LD50(rat, oral): > 2000 mg/kg bw

A study for dermal exposure is not available.

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:

key study

Study period:

14.11.1988-28.11.1988

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Animals were kept in groups of 5 in Makrolon cages at 22 ±3 °C and 50 ±20% relative humidity with 12 hours ilumination per day. The acclimatisation period prior to dosing was minimum 5 days. 16 hours before application and 3 - 4 hours thereafter no feed was provided. Water was orvided ad libitum. Animals were individually marked with KMnO4 marks on fur and cages were clearly identifiable.

Route of administration:

oral: gavage

Vehicle:

other: sesame oil

Doses:

2000 mg/kg
concentration: 20%(w/v)
application volume: 10 ml/kg bw

No. of animals per sex per dose:

5 males and 5 females

Control animals:

no

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality after 14 days observation

Clinical signs:

other: Obserced symtoms 4 - 6 h after application: crouch position, drawn-in flanks, irregular breathing (only male), reduced activity, uncoordinated movement (only female). After one day no symptoms were observed.

Gross pathology:

without finding

Other findings:

no other findings

Interpretation of results:

GHS criteria not met

Conclusions:

The LD50 in this study was >2000 mg/kg bw; no mortality was observed.

Executive summary:

The study on acute oral toxicity of Additol XL 465 (Hoechst name of EC 258-981-8 N,N'-(methylenedi-p-phenylene)bis[hexahydro-2-oxo-1H-azepine-1-carboxamide]) on male and female Wistar-rats results in a LD50 of >2000 mg/kg bw. After application of 2000 mg/kg bw no mortality was observed but slight symptoms.

At the day of application the animals showed symptoms crouch position, drawn-in flanks, irregular breathing (only male), reduced activity, uncoordinated movement (only female). From second day there were no symptoms observed.

No pathologic finding was observed.

The development of body weight was normal.

The result of the study is sufficient for classification.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from August 28 to December 12, 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.2 (Acute Toxicity (Inhalation))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

Animals
Species / Strain / Stock: Rat (Rattus norvegicus) / CD / Crl:CD(SD)
Breeder: Charles River Laboratories, Research Models and Services, Germany GmbH, Sandhofer Weg 7 97633 Sulzfeld Germany
Age: (at start of exposure): Males: approx. 8 weeks Females: approx. 9 weeks
Body weight shortly before start of the exposure: Males: 262 - 267 g; Females: 222 - 231 g
Selection of species: The rat is a commonly used rodent species for such studies.
Identification of animals: By coloured tail marks and cage label
Number of animals: 10 (5 males and 5 females)
Groups: 1 concentration - Limit test
Concentrations: nominal: 6.67 mg/L air (mean achieved: 5.07 mg/L air, SD = 0.03 mg/L air)
Duration of experiment: at least 5 adaptation days 1 test day, 2 recovery weeks

Housing
Granulated textured wood (Granulat A2, J. Brandenburg, 49424 Goldenstedt, Germany) was used as bedding material for the cages. The cages were changed and cleaned twice a week.
Periodic analysis of the bedding material for contaminants based on EPA/USA is conducted at least once a year by LUFA-ITL (see Appendix 2: Limitation for contaminants in the bedding material).
During the 14-day observation period the animals were kept by sex in groups of 2 - 3 animals in MAKROLON cages (type III plus) at a room temperature of 21.8 °C - 25.0 °C and a relative humidity of 48% ±68%. The ranges are given with 22 °C ±3 °C (maximum range) and a relative humidity of 55% ±15% (maximum range). Deviations from the maximum range caused for example during cleaning procedures are dealt with in SOPs.
The rooms were lit (150 lux at approx. 1.50 m room height) and darkened for periods of 12 hours each.
Drinking water in bottles was offered ad libitum. Feeding was discontinued approx. 16 hours before administration; only tap water was then available ad libitum.

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose only

Vehicle:

air

Details on inhalation exposure:

Route of administration: By inhalation (nose-only exposure)
Duration of exposure to the test item: 4 hours/animal
Exposure concentration: 5.07 mg/L air (mean actual concentration)
Exposure system
The study was carried out using a dynamic inhalation chamber (air changes/h (≥ 12 times)) with a nose-only exposure of the animals according to KIMMERLE & TEPPER. The apparatus consists of a cylindrical exposure chamber (volume 40 L) which holds the animals in pyrex tubes at the edge of the chamber in a radial position.
The dust of the test material was generated with a rotating brush dust generator.
The generator was fed with compressed air (5.0 bar) from a compressor (air was taken from the surrounding atmosphere of the laboratory room and filtered using an in-line disposable gas-filter).
At the bottom of the exposure chamber, the air was sucked off at a lower rate than created by the dust generator in order to produce a homogenous distribution and a positive pressure in the exposure chamber (inflow 900 L/h, outflow 800 L/h).
A manometer and an air-flow meter were used to control the constant supply of compressed air and the exhaust, respectively. Flow rates were checked hourly and corrected if necessary.
The oxygen content in the inhalation chamber was 21% v/v. It was determined at the beginning and at the end of the exposure with a DRÄGER Oxygen-analysis test set (DRÄGER Tube Oxygen 67 28 081).
The whole exposure system was mounted in an inhalation facility to protect the laboratory staff from possible hazards.
The exhaust air was sucked through gas wash-bottles. Exposure started by locating the rats into the exposure chamber after equilibration of the chamber concentration for 15 minutes.
Analysis of the dust concentration
The actual dust concentration in the inhalation chamber was measured 4 times gravimetrically with an air sample filter (Minisart SM 17598; 0.45 µm) and pump controlled by a rotameter. Dust samples were taken once every hour during the exposure. For that purpose, a probe was placed close to the animals' noses in the inhalation chamber and air was sucked through the air sample filter at a constant flow of air of 5 L/min for 1 minute. The filters were weighed before and after sampling on an analytical balance (accuracy 0.1 mg).
Temperature and humidity: The temperature (22 °C ±3 °C) and humidity was checked and noted once every hour during the exposure period of the experiment.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

ca. 4 h

Concentrations:

a single dose of 5.07 mg/L air

No. of animals per sex per dose:

5 males and 5 females

Control animals:

no

Details on study design:

After completion of exposure, the animals were observed for a period of 14 days. During and following exposure, observations were made and recorded systematically; individual records were maintained for each animal. A careful clinical examination was made at least once daily until all symptoms subsided, thereafter each working day. Observations on mortality were made at least once daily to minimize loss of animals to the study.
Cageside observations included but were not limited to: changes in the skin and fur, eyes, mucous membranes, respiratory, circulatory, autonomic and central nervous system, as well as somatomotor activity and behaviour pattern.
Particular attention was directed to observation of tremor, convulsions, salivation, diarrhoea, lethargy, sleep and coma.
Individual body weights of animals were determined before the exposure on test day 1 and on test days 8 and 15. Changes in weight were calculated and recorded when survival exceeds one day. At the end of the test, all animals were weighed and sacrificed.
Pathology
Necropsy of all animals was carried out and all gross pathological changes were recorded.
No microscopic examination was carried out as no pathological findings were noted at necropsy.
Due to lack of prematurely deceased animals no LC50 could be calculated.

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 5 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: None of the animals died prematurely after exposure of test article. All animals gained the expected body weight.

Mortality:

None of the animals died prematurely.

Clinical signs:

other: Slight ataxia, slight tremor, slightly reduced muscle tone and slight dyspnoea immediately until 30 minutes or 3 hours after end of exposure in all 5 of 5 male and 5 of 5 female animals. No clinical observations were observed during the further 14-day obs

Body weight:

All animals gained the expected body weight. No treatment-related body weight effects were seen neither for males nor females over the 14-day period as all animals gained the expected body weight.

Gross pathology:

No pathological findings were noted at necropsy.

Other findings:

no data

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the available data in this study, LC50(rat, 4 hours) of test article was greater than 5 mg/L air.

Executive summary:

This acute study was performed to assess the acute inhalation toxicity of test item administered to rats for a single 4-hour period at a mean actual concentration of 5.07 mg/L air using a dynamic nose-only exposure chamber. The particle size distribution was determined with a cascade impactor. Under the present test conditions, a 4-hour exposure to Grilbond IL-6 100% at the concentration of 5.07 mg/L air revealed slight ataxia, slight tremor, slightly reduced muscle tone and slight dyspnoea immediately until 30 minutes or 3 hours after end of exposure in all 5 of 5 male and 5 of 5 female animals. None of the animals died prematurely. All animals gained the expected body weight. No pathological findings were noted at necropsy.

Therefore, LC50 of test item for rats is greater than 5.07 mg/L air for 4 hour.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

5 070 mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The acute toxicity of the test item was evaluated in a key oral (gavage) study and a key inhalation study.

According to REACH 1907/2006, Annex VIII, column 2, 8.5, in addition to oral route, for substance other than gases, the information mentioned under 8.5.2 to 8.5.3 shall be provided for at least one other route. Thus, the safety assessment concern of acute dermal toxicity is unnecessary as the data of acute toxicity by oral and inhalation route are available and sufficient for assessment of acute toxicity of test article.

 

The study on acute oral toxicity of the substance on male and female Wistar-rats results in a LD50 of > 2000 mg/kg bw. After application of 2000 mg/kg bw no mortality was observed but slight symptoms.

At the day of application, the animals showed symptoms such as crouch position, drawn-in flanks, irregular breathing (only male), reduced activity, uncoordinated movement (only female). From second day on there were no symptoms observed. No pathologic finding was observed. The development of body weight was normal. The result of the study is sufficient for classification.

The acute inhalation study was performed to assess the acute inhalation toxicity of test item administered to rats for a single 4-hour period at a mean actual concentration of 5.07 mg/L air using a dynamic nose-only exposure chamber. Under the present test conditions, a 4-hour exposure to Grilbond IL-6 100% at the concentration of 5.07 mg/L air revealed slight ataxia, slight tremor, slightly reduced muscle tone and slight dyspnoea immediately until 30 minutes or 3 hours after end of exposure in all 5 males and all 5 female animals. None of the animals died prematurely. All animals gained the expected body weight. No pathological findings were noted at necropsy. The LC50 of the test item for rats is therefore greater than 5.07 mg/L air (4-hour exposure).

Justification for selection of acute toxicity – dermal endpoint: According to REACH 1907/2006, Annex VIII, column 2, 8.5, in addition to the oral route, for substance other than gases, the information mentioned under 8.5.2 to 8.5.3 shall be provided for at least one other route. Thus, the acute dermal toxicity study can be waived if the data of acute toxicity by oral and inhalation route are available and sufficient for assessment of acute toxicity of test article. As the inhalation of dust is the most likely route of exposure to the substance, this approach is justified.

Justification for classification or non-classification

Based on the available data, Grilbond IL-6 100% is not to be classified in accordance with CLP (Regulation EC No.1272/2008) for acute oral or acute inhalation toxicity. Data for acute dermal toxicity is lacking, but toxicity is very unlikely. Thus, the substance is not classified for acute toxicity.