2-(4-(diethylaminopropylcarbamoyl)phenylazo)-3-oxo-N-(2,3-dihydro-2-oxobenzimidazol-5-yl)butyramide

Endpoint summary

Description of key information

A 28 day oral toxicity in male and female rats up to 1000 mg/kg bw/d lead to no substance related effects. The NOEL was considered to be 1000 mg/kg bw/.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Nov 1989

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Version / remarks:

1981

Deviations:

no

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Wistar

Remarks:

Hoe:WISKf

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hoechst AG, Kastengrund, Germany
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 6 weeks
- Weight at study initiation:
males: 127 g (mean)
females: 124 g (mean)
- Housing:
in fully air-conditioned rooms in Macrolon cages type 3, on softwood granulate in groups of 5 animals
- Diet (e.g. ad libitum): rat/mice diet Altromin 1324 (Altromin GmbH, Lage/Lippe), ad libitum (except period in which animals were housed in metabolism cages)
- Water (e.g. ad libitum): tap water in plastic bottles, ad libitum (except period in which animals were housed in metabolism cages)
- Acclimation period: at least 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22+/-3°C
- Humidity (%): 50+/-20%
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES:
From: 2. Nov To: 30.Nov. 1989

Route of administration:

oral: gavage

Vehicle:

other: sesame oil

Details on oral exposure:

- PREPARATION OF DOSING SOLUTIONS:


- VEHICLE
- Justification for use and choice of vehicle (if other than water): homogenity of suspension
- Concentration in vehicle:
62.5 mg/kg bw/d: 1.25% (w/v)
250 mg/kg bw/d: 5% (w/v)
1000 mg/kg bw/d: 20% (w/v)
- Amount of vehicle (if gavage): 5 mL/kg bw

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

no data

Duration of treatment / exposure:

28 days

Frequency of treatment:

once daily

Dose / conc.:

62.5 mg/kg bw/day (actual dose received)

Dose / conc.:

250 mg/kg bw/day (actual dose received)

Dose / conc.:

1 000 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

5

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
- Rationale for animal assignment (if not random): n.a., randomised
- Post-exposure recovery period in satellite groups: none, not required since no effects occurred

Positive control:

none

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: twice weekly

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes, food consumption/100 g bw/d


FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Yes
- Time schedule for examinations: weekly

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at study termination
- Anaesthetic used for blood collection: Yes, nembutal
- Animals fasted: No
- How many animals: all
- Parameters checked:
erythrocyte count, haemoglobin, haematocrit, leucocyte count, thromobcyte count, differential blood cell count, reticulocyte count, Heinz corpuscular count, coagulation time

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at study termination
- Animals fasted: No
- How many animals: all
- Parameters checked:
sodium, otassium, inorganic phosphorus, uric acid, creatinine, glucose, urea, calcium, chloride, alanine aminotransferase (ALAT), aspartate-aminotransferase (ASAT), alkaline phosphatase, gamma-glutamyl peptidase, protein, albumin, globuline

URINALYSIS: Yes
- Time schedule for collection of urine: from day 26 to 27 overnight
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes
- Parameters checked:
appearance, color, pH, haemoglobin, protein, glucose, keton bodies, bilirubine, urobilirubine, density, dediment

NEUROBEHAVIOURAL EXAMINATION: No

IMMUNOLOGY: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
Organ weight: heart, lung, liver, kidneys, spleen, testis, epididymis

HISTOPATHOLOGY: Yes
heart, lung, liver, kidneys, spleen, stomach, jejunum, colon, thymus, testis, epidiymis, bone marrow (femur)

Statistics:

body weight, body weight gain, haematology, clinical chemistry, absolute and relative organ weight, pH and specific gravity of urine

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

males:
decreased bilirubine at 1000 mg/kg bw/d. However, since the value is above the bilirubine measured in control and low dose females this decreased is considered to be non-treatment-related

Urinalysis findings:

no effects observed

Behaviour (functional findings):

no effects observed

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

Absolute weight of testes was decreased in high dose males. However, since the weights were still within the physiological normal range this decrease is considered to be not of biological relevance.
Lung weights were decreased in mid and high dose females. This effect did not follow a dose-response relationship, thus it is not considered as treatment-related.

Gross pathological findings:

no effects observed

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Key result

Dose descriptor:

NOEL

Effect level:

1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no treatment-related effects observed

Key result

Critical effects observed:

no

Conclusions:

Based on the results of the 28 day oral toxicity study and the absence of effects the NOEL is derived at 1000 mg/kg bw/d.

Executive summary:

The aim of this study was to assess the possible health hazards which could arise from repeated exposure of the substance via oral administration to rats over a period of 28 days.

The test item was administered daily in graduated doses to 3 groups of test animals, one dose level per group for a treatment period of 28 days. Animals of an additional control group were handled identically as the dose groups but received sesame oil, the vehicle used in this study. The 4 groups comprised of 5 male and 5 female Wistar rats.

During the period of administration, the animals were observed precisely each day for signs of toxicity. At the conclusion of the test, surviving animals were sacrificed and observed macroscopically and microscopically.

Body weight and food consumption were measured twice weekly, the water consumption onece weekly. At study termination urainlysis, heamtology and clinical chemistry was performed in all animals.

At the conclusion of the treatment period all animals were sacrificed and subjected to necropsy. The wet weight of a subset of tissues was taken and a set of organs/tissues was preserved.

A histopathological evaluation of the tissues was performed on all animals.

The following doses were evaluated:

Control:                        0         mg/kg body weight

Low Dose:                   62.5     mg/kg body weight

Medium Dose:             250    mg/kg body weight

High Dose:                  1000  mg/kg body weight

The test item formulation was prepared freshly on each day of administration. Dose volumes were adjusted individually based on weekly body weight measurements.

No test item related effects were observed in all animals.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

reliable without restrictions

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Mode of Action Analysis / Human Relevance Framework

In the absence of any evidence for species specific effects or modes of action the effects observed in animals are regarded as relevant for humans.

Additional information

An OECD 407 with the test substance was performed in rats.

The test item was administered daily in graduated doses to 3 groups of test animals, one dose level per group for a treatment period of 28 days. Animals of an additional control group were handled identically as the dose groups but received sesame oil, the vehicle used in this study. The 4 groups comprised of 5 male and 5 female Wistar rats.

During the period of administration, the animals were observed precisely each day for signs of toxicity. At the conclusion of the test, surviving animals were sacrificed and observed macroscopically and microscopically.

Body weight and food consumption were measured twice weekly, the water consumption onece weekly. At study termination urainlysis, heamtology and clinical chemistry was performed in all animals.

At the conclusion of the treatment period all animals were sacrificed and subjected to necropsy. The wet weight of a subset of tissues was taken and a set of organs/tissues was preserved.

A histopathological evaluation of the tissues was performed on all animals.

The following doses were evaluated:

Control:                        0         mg/kg body weight

Low Dose:                   62.5     mg/kg body weight

Medium Dose:             250    mg/kg body weight

High Dose:                  1000  mg/kg body weight

The test item formulation was prepared freshly on each day of administration. Dose volumes were adjusted individually based on weekly body weight measurements.

No test item related effects were observed in all animals.

Justification for classification or non-classification

Due to the NOEL of 1000 mg/kg bw/day in an OECD 407 repeated dose toxicity study in rats the substance has not to be labelled according to the criteria laid down in the Regulation (EC) No 1272/2008.