Synthetic resin, a reaction product of 4,4'-bis(N-maleimido)diphenylmethane with 3-aminobenzoic acid hydrazide

Endpoint summary

Description of key information

- study conducted according to OECD guideline 401, GLP, 5 female and male Wistar rats were exposed to 2000 mg/kg bw of 1,1'-(methylenedi-p-phenylene)bismaleimide applied as a single dose via gavage and observed for 15 days, not mortality, no clinical signs detected, LD50 > 2000 mg/kg bw, read-across

- study conducted according to OECD guideline 401, GLP, 5 female and male Wistar rats per dose group were exposed to 200, 800 and 2000 mg/kg bw of 3 -aminobenzohydrazide applied as a single dose via gavage and observed for 15 days, base on clinical sings and premature mortality the LD50 was determined to be 1390.97 mg/kg bw (adjusted to the amount of 3-aminobenzohydrazide present in the final product: LD50 = 9151.12 mg/kg bw), read-across

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1989-10-24 to 1990-01-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

February 1987

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Version / remarks:

March, 1984

Deviations:

no

GLP compliance:

yes

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:

TEST ANIMALS
- Age at study initiation: males 9 weeks, females 11 weeks
- Weight at study initiation: males 187-205 g, females 173-187 g
- Fasting period before study: 12-18 hours
- Housing: 5 animals per cage; Makrolon type-3 cages with standard softwood bedding ("Lignocel", Schill AG, CH-4132 Muttenz)
- Diet: ad libitum, pelleted Kliba 343, Batch 55/89 rat maintenance diet ("Kliba", Klingenmuehle AG, CH-4303 Kaiseraugst)
- Water: ad libitum, community tap water from Itingen
- Acclimation period: one week under laboratory conditions, after veterinary examination

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 40-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg


MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg

DOSAGE PREPARATION: The test article was placed into a glass beaker on a tared Mettler PE 360 balance, and the vehicle (bi-distilled water) was added. A weight by volume dilution was prepared using a homogenizer (Ultr-Turrax, Janke and Kunkel, Staufen). Homogeneity of the test article in the vehicle was maintained during treatment using a magnetic stirrer (Janke and Kunkel, Staufen). The preparation was made immediately prior to each dosing.

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 15 days
- Frequency of observations: at 1, 2, 3 and 5 h after dosing and once daily thereafter
- Frequency of weighing: Test days 1 (pre-administration), 8 and 15.
- Necropsy of survivors performed: yes

Statistics:

No statistics applied.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No adverse effects observed during the study

Mortality:

The following death rate was observed: 0% at 2000 mg/kg

Clinical signs:

other: Each animal was examined for changes in appearance and behavior four times during day 1, and daily during days 2-15. All abnormalities were recorded. No systemic signs were observed in any animal throughout the entire study.

Gross pathology:

Necropsies were performed by experienced prosectors. All animals were necropsied. All animals were killed by intraperitoneal injection of sodium pentobarbitone. The following macroscopical organ changes were observed: 2000 mg/kg: sacrificed - lungs: discoloration, dark red

Interpretation of results:

not classified

Conclusions:

The acute oral toxicity of the test material in Wistar rats of both sexes, observed over a period of 15 days, was estimated to be greater than 2000 mg/kg, thus, the test item is not classified according to Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized System for Classification and Labelling of Chemicals (GHS) with respect to acute oral toxicity.

Reference 2

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1989-10-23 to 1990-01-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

adopted February 24, 1987

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Version / remarks:

not reported

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: females: 11-12 weeks; males: 9-10 weeks
- Weight at study initiation: females: 162-198 g; males: 181-228 g
- Fasting period before study: 15 to 22 h
- Housing: groups of five in Makrolon type-3 cages with standard softwood ("Lignocel", Schill AG, CH-4132 Muttenz).
- Diet (e.g. ad libitum): ad libitum Kliba 343, Batches 55/89 and 60/89 rat maintenance diet ("Kliba", Klingenmühle AG, CH-4303 Kaiseraugst)
- Water (e.g. ad libitum): ad libitum Community tap water from Itingen
- Acclimation period: One week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 40-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

4% solution in bi-distilled water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 20, 80, 200 mg/mL
- Amount of vehicle (if gavage): 4% in bi-distilled water

MAXIMUM DOSE VOLUME APPLIED: 10 mL

DOSAGE PREPARATION: prepared immediately prior to dosing

Doses:

200, 800 and 2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 15 days
- Frequency of observations and weighing: four times during day 1 and daily during day 2-15, body weights were recorded at days 1 (pre-administration), 8 and 15
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, gross pathology

Statistics:

The LOGIT-Model (COX, Analysis of Binary Data, London, 1977) was applied nto estimate the toxicity value. Additionally, the 90, 95 and 99% confidence limits for the toxicity for each sex and slope of the dose response line were estimated.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

1 390.97 mg/kg bw

Based on:

test mat.

95% CL:

>= 837.82 - <= 3 581.7

Remarks on result:

other: LOGIT-Model

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

773.38 mg/kg bw

Based on:

test mat.

95% CL:

>= 370.52 - <= 1 897.45

Remarks on result:

other: LOGIT-Model

Key result

Sex:

male

Dose descriptor:

LD50

Effect level:

3 864.45 mg/kg bw

Based on:

test mat.

Remarks on result:

other: LOGIT-Model

Mortality:

Two males of the 2000 mg/kg dose group died on day 1, 3h and 5h after administration.
Two females of the 800 mg/kg dose group died on day 1, 2h and 3h after administration and all females of the 2000 mg/kg dose group died within the first two days after administration, 4 females died on day 1, 3h and 5h after administration and 1 animal died on day 2.

Clinical signs:

other: Clinical signs observed were, sedated behaviour, spasms, huntched posture and ruffled fur. Clinical signs did not occur in the 200 mg/kg dose group neither in female nor male animals. In the 800 mg/kg dose group 4 female showed the clinical signs mentione

Gross pathology:

In the male 2000 mg/kg dose group, dark red discoloured lungs were observed in one of the 2 premature died animals. In the female 200 mg/kg group one animal showed pale discoloured lungs during necropsy after the 15 days observation period.
Both premature died female animals of the 800 mg/kg group had dark red discoloured lungs. In the 2000 mg/kg group all female animals died spontaneously and exhibit dark red discoloured lungs.

Table 1: LD 50 estimation (LOGIT-Model):

Dose mg/kg	No. of animals	No. of responses	% of responses
200	10	0	0.0
800	10	2	20.0
2000	10	7	70.0
LD50 estimate		1390.97 mg/kg
95%   confidence limits		[837.82 - 3581.70]

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

In the present study conducted according to OECD 401 (adopted February 24, 1987) each 5 female and male Wistar rats per group were administered 200, 800 and 2000 mg/kg 3-aminobenzohydrazide via gavage. Thereafter, the animals were observed for additional 15 days.
Two premature deaths occurred in the female 800 mg/kg dose group, and two in the male 2000 mg/kg dose group. In the female 2000 mg/kg dose group all animals died within the first two days after administration. Clinical signs were observed in all premature died animals but also in the 800 mg/kg dose group and 2000 mg/kg dose group irrespective of sex. Gross pathology revealed dark red discoloured lungs in the spontaneously died animals. The LD50 was calculated using the LOGIT-Model. The LD50 of 3-aminobenzohydrazide is 773.38 mg/kg in female rats, 3864.45 mg/kg in male rats and 1390.97 mg/kg in female/male rats. Thus, the test substance is classified into Category 4 " Harmful if swallowed" based on Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized System for Classification and Labelling of Chemicals (GHS).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Quality of whole database:

The studies were conducted according to OECD guidelines and GLP-compliant, thus, the quality of the results is considered high.

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:

10 May 2012 - 28 September 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted in accordance with official OECD test guidelines and in compliance with GLP; on this basis the data is considered reliable without restrictions.

Qualifier:

according to guideline

Guideline:

OECD Guideline 436 (Acute Inhalation Toxicity: Acute Toxic Class Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Species:

rat

Strain:

other: Crl:CD (SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 8 to 10 weeks
- Weight at study initiation: 326 to 376 g (Males) or 215 to 257 g (Females)
- Housing: Polycarbonate cages with stainless steel mesh lids.
- Diet (e.g. ad libitum): Free access to diet whilst in home cage.
- Water (e.g. ad libitum): Free access to potable water.
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 23°C
- Humidity (%): 40 to 70%
- Photoperiod (hrs dark / hrs light): 12 hours / 12 hours.

IN-LIFE DATES: From: 14 May 2012 To: 31 July 2012

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose only

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Snout-only inhalation chamber
- Exposure chamber volume: Approximately 30 litres; a chamber liner was added filling 9.9 liters, giving a final volume of 20.1 liters.
- Method of holding animals in test chamber: Restraining tubes
- Source and rate of air: Compressed air, 25 litres/minute
- Method of conditioning air: Filtered and dried
- System of generating particulates/aerosols: Wright Dust Feed (WDF)
- Method of particle size determination: Atmosphere samples from chamber were drawn through a Cascade Impactor using a pump.
- Treatment of exhaust air: Extraction system incorporated a filtration system to remove particulate material.
- Temperature, humidity, pressure in air chamber: Mean temperature = 23.8°C (group 1), 22.6°C (group 2), 22.6°C (group 3). Mean relative humitidy = 48.3% (group 1), 16.6% (group 2), 9.7% (group 3).

TEST ATMOSPHERE
- Brief description of analytical method used: Gravimetric analysis of glass fibre filters over which a known volume of the test atmosphere was drawn. Mean of five measurements during exposure period was used.
- Samples taken from breathing zone: yes

TEST ATMOSPHERE (if not tabulated)
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.):
Group 1 (average achieved chamber concentration = 2.02 mg/L): Mean MMAD = 4.0µm; GSD = 2.33
Group 2 (average achieved chamber concentration = 1.09 mg/L): Mean MMAD = 3.8µm; GSD = 2.53
Group 3 (average achieved chamber concentration = 0.515 mg/L): Mean MMAD = 3.5µm; GSD = 2.27

Analytical verification of test atmosphere concentrations:

yes

Remarks:

See details above

Duration of exposure:

4 h

Concentrations:

Group 1: Target concentration = 2 mg/L; Average achieved chamber concentration = 2.02 mg/L
Group 2: Target concentration = 1 mg/L; Average achieved chamber concentration = 1.09 mg/L
Group 3: Target concentration = 0.5 mg/L; Average achieved chamber concentration = 0.515 mg/L

No. of animals per sex per dose:

3 males and 3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations taken at least twice daily. Bodyweights recorded during acclimatisation, on day 1 prior to dosing, and on days 2,4,8, and 15.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, macroscopic pathology

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 0.515 - < 1 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Mortality:

2 males and 2 females died at 2.02 mg/L.
3 males and 1 female died at 1.09 mg/L.
2 males died at 0.515 mg/L.

Clinical signs:

other: At 2.02 mg/L two males died on the day of the exposure, clinically they were observed to have deep or noisy breathing; in addition one male was noted as having reduced activity with a hunched posture and closed eyelids. There were also two decedent female

Body weight:

Bodyweight losses were observed in the surviving males from Groups 1 and 3 up until Day 4, after which growth was observed until Day 15.

Bodyweight losses were observed in all surviving females on the day following the exposure; recovery was evident by the next weighing occasion after which growth continued until Day 15.

In all decedent animals the terminal bodyweights were lower than the weights recorded prior to the start of the exposure.

Gross pathology:

The macroscopic examinations performed revealed a number of findings in the lungs. These comprised dark discoloration, incomplete collapse, firmness, adhesions and some pale areas in animals treated with 2.02 or 1.09 mg/L, many of which were found dead. Associated findings such as fluid in the thorax and gaseous distension of the gastrointestinal tract were also seen in some animals at these exposure levels.

A few pale areas in the lungs were observed in the four terminal animals treated with 0.515 mg/L. Enlargement of the tracheobronchial lymph nodes was also noted in these animals. The two decedent animals at 0.515 mg/L showed dark discoloration, incomplete collapse and firmness of the lungs consistent with the findings observed in the other groups.

Interpretation of results:

Toxicity Category III

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study the LC50 (4-hour) of BMI is in excess of 0.515 mg/L but not exceeding 1 mg/L for male and female rats.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LC50

Value:

515 mg/m³ air

Quality of whole database:

The study was conducted according to OECD guidelines and GLP-compliant, thus, the quality of the results is considered high.

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

There are no experimental data on the target substance Compimide 183 available. However, acute toxicity studies are available for the source substance MDAB and ABH. A detailed justification for read-across is attached to IUCLID section 13.

Acute oral toxicity

No acute oral toxicity data are available for the target substance Compimide 183.

Acute oral toxicity studies are available for both source substances.

In an acute oral toxicity study conducted according to OECD guideline 401, 5 female and male Wistar rats were treated with MDAB in a single dose of 2000 mg/kg bw. The animals were observed for 15 days and all signs of toxicity and mortality were recorded. The results revealed no signs of toxicity during the observation period of 15 days. Thus, the LD50 was found to be > 2000 mg/kg bw.

In an acute oral toxicity study conducted according to OECD guideline 401 also ABH was tested in 5 female and male Wistar rats at concentrations of 200, 800 and 2000 mg/kg bw by oral gavage and observed for 15 days. Two animals, one female and one male, showed weight loss between day 8 and 15, there were also clinical observations in the 800 and 2000 mg/kg bw groups indicating a toxic effect. Predominant effects were sedated appearance, hunched posture, spasms and ruffled fur. Thus, the Logit estimation for the LD50 was 1390.97 mg/kg bw. Based on the distribution of ABH in Compimide 183 (approximately 15% in the final product) the LD50 of ABH was adjusted to 9151.12 mg/kg bw.

Acute inhalation toxicity

No acute inhalation toxicity study is available for the target substance Compimide 183.

In an acute inhalation toxicity study with the source substance MDAB conducted in accordance with OECD guideline 436, groups of 3 rats per sex and concentration level were nose-only exposed to MDAB at 0.515, 1.09 and 2.02 mg/L for 4 h. Mortality occurred at the low (2 males), middle (3 males and 1 female) and high dose (2 males and 2 females). Clinical signs of the animals which died in the 2.02 mg/L group included deep or noisy breathing, reduced activity, hunched posture and closed eyelids. At 1.09 mg/L reduced body temperature, reduced activity with irregular, fast or deep breathing, and struggling in the restraint tube were noted. Animals in the 0.515 mg/L group had irregular or deep breathing and partially closed eyelids.

Surviving animals of all groups showed clinical sings similar to those described above for each group, but these did not lead to mortality and were reversible within 3 to 6 days. In all decedent animals the terminal bodyweights were lower than the weights recorded prior to the start of the exposure. Transient body weight reduction was seen in all surviving animals. The macroscopic examinations performed revealed a number of findings in the lungs. These comprised dark discoloration, incomplete collapse, firmness, adhesions and some pale areas in animals treated with 2.02 or 1.09 mg/L, many of which were found dead. Associated findings such as fluid in the thorax and gaseous distension of the gastrointestinal tract were also seen in some animals at these exposure levels. A few pale areas in the lungs were observed in the four terminal animals treated with 0.515 mg/L. Enlargement of the tracheobronchial lymph nodes was also noted in these animals. The two decedent animals at 0.515 mg/L showed dark discoloration, incomplete collapse and firmness of the lungs consistent with the findings observed in the other groups.

Acute dermal toxicity

According to Regulation (EC) No 1907/2006 (REACH), Annex VII for registrations of 1-10 t/a experimental data on acute dermal toxicity is not necessary.

Based on the available information, the acute oral toxicity of Compimide 183 is low. Results of an acute inhalation toxicity study conducted with the source substance MDAB revealed a LC50 of 0.515 mg/L air, thus, the acute toxicity by inhalation route is high. Based on the read-across hypothesis and for precautionary reasons Compimide 183 is classified as toxic if inhaled. There are no data gaps in acute toxicity. Even though there is no information on acute toxicity in humans, there is no reason to believe that the low acute toxicity observed in experimental animals would not be relevant for human health.

Justification for classification or non-classification

Due to the obtained results from the acute oral toxicity study conducted with 1,1'-(methylenedi-p-phenylene)bismaleimide (LD50 > 2000 mg/kg bw) and 3 -aminobenzohydrazide which revealed a LD50 of 9151.12 mg/kg bw (adjusted to the amount of the reactant in the final product) the test substance Compimide 183 does not need to be classified based on Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized System for Classification and Labelling of Chemicals (GHS) with respect to acute oral toxicity.

In a acute inhalation toxicity study conducted with 1,1'-(methylenedi-p-phenylene)bismaleimide the LC50 was determined to be between 0.51 mg/L and 1 mg/L, thus Compimide 183 is classified as acute inhalation toxicity Category 3: toxic if inhaled according to Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized System for Classification and Labelling of Chemicals (GHS).