N-(4-ethoxyphenyl)-3-hydroxy-4-[(2,4,5-trichlorophenyl)azo]naphthalene-2-carboxamide

Endpoint summary

Description of key information

Groups of male and female Wistar rats received the analogue substance Pigment Red 170 at concentrations of 0, 500, 2500 or 12500 mg/kg food for a period of 28 days and were necropsied at day 29.

Behaviour and state of health were observed daily in all groups. Body weights and food consumption were recorded twice weekly and water consumption once weekly.

Hematological examinations, clinical chemistry and urine analysis were carried out at the termination of the study.

During necropsy the animals were examined for macroscopically visible abnormalities, the main organs weighed and the organ to bodyweight ratios calculated.

Many organs and tissues were processed for histopathological examination and checked for microscopically visible changes.

Body weights, hematological and clinical chemistry data, urine data (volume, pH value and specific weight), absolute and relative organ weights were analysed with the aid of a statistical program to show differences compared with the controls.

According to food consumption, mean substance intakes were as follows:

Males - low dose group               47 mg/kg bodyweight per day

intermediate dose group          227 mg/kg bodyweight per day

high dose group                      1172 mg/kg bodyweight per day

Females - low dose group      46 mg/kg bodyweight per day

intermediate dose group        236 mg/kg bodyweight per day

high dose group                          1193 mg/kg bodyweight per day

Behaviour and general health condition remained unaffected by the administration of the test compound in all groups. Body weight development, food and water consumption were comparable in all groups.

No signs of neurological disturbances, opacity of the refracting media of the eyes, damage to the oral mucosa or impairment of dental growth were observed in the control or treatment groups.

Hematological and clinical chemistry examinations revealed no abnormalities. No treatment-related changes were observed by urine analysis.

Organ weights were not affected by the administration of the test compound.

No compound-related effect was observed at necropsy.

The histopathological examinations revealed test compound in the lumen of the alimentary tract, adherent to the surface of the mucous membrane and/or the

food. The mucous membranes itself were uninjured.

In conclusion, Pigment Red 170 caused no detectable adverse effects in male and female Wistar rats when administered via food at the concentration of 12500 mg/kg food for 28 days.

With regard to the present study the 'No Observed Effect Level' is 12500 mg test item / kg food. This is equivalent to a mean daily compound intake of

1172 mg/kg bodyweight in males and 1193 mg/kg bodyweight in females.

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:

1992-06-03 - 1992-07-01

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 (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Wistar

Remarks:

HOE: Wisk (SPF71)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hoechst AG Frankfurt, Germany
- Females (if applicable) nulliparous and non-pregnant: [yes]
- Age at study initiation: not specified
- Weight at study initiation: Male: 134-137 g; female: 114 -117 g
- Fasting period before study: no
- Housing: groups of 5 in wire mesh cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 C
- Humidity (%):50 +/- 20%
- Air changes (per hr): not specified
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Remarks:

admixture in food

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

28 days

Frequency of treatment:

daily

Dose / conc.:

0 mg/kg diet

Remarks:

Control

Dose / conc.:

500 mg/kg diet

Dose / conc.:

2 500 mg/kg diet

Dose / conc.:

12 500 mg/kg diet

No. of animals per sex per dose:

5

Control animals:

yes, plain diet

Positive control:

no

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations included: general behaviour & health, neurological abservations, teeht, eyes.

DETAILED CLINICAL OBSERVATIONS: Not specified
- Time schedule:

BODY WEIGHT: Yes
- Time schedule for examinations: 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, twice weekly
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Not specified

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: Not specified

HAEMATOLOGY: Yes
- Time schedule for collection of blood: end of study
- Anaesthetic used for blood collection: Not specified
- Animals fasted: No
- How many animals: all
- Parameters were examined: RBC. Hb, Hematocrit, MCV, MCH, MCHC, Leuco, Platelets, Diff. Leuco, Rei, Heinzbodies, coagulation time

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: end of study
- Animals fasted: No
- How many animals: all
- Parameters examined: Na, K, PO4, Uric acid, Bilirubin, Creatinine, Glucose, Ca, Cl, ASAT, ALAT, AP, gamma GT, Cholesterol, triglycerides, Tot. protein, tot. Lipids, Albumen, urea nitrogen

URINALYSIS: Yes
- Time schedule for collection of urine: shortly before end of study
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Not specified
- Parameters examined: Appearance, colour, Volume, pH, Hb, Protein, Glucose, Ketone bodies, Bilirubin, Urobiinogen, density, sediment,

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations:daily,
- Dose groups that were examined: all
- Battery of functions tested: sensory activity , other: general observations

IMMUNOLOGY: No

OTHER:

Sacrifice and pathology:

GROSS PATHOLOGY: Yes

HISTOPATHOLOGY: Yes
Organweights: Heart lung, liver, kidneys, spleen
Histopathology: Heart lung, liver, kidneys, spleen, stomach, jejunum,colon, urinary bladder, testes,epididymides, prostate, seminal vesicles, ovaries, uterus, adrenals, thymus, brain, nstrachea, bone marrow (femur), skeletal muscle, nervus ischiadicus, spinal cord (3 locations), lymphnodes (2 locations)

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

The red colouration of feces and fur is considered a non-adverse effect of the coloured test item.

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:

no effects observed

Haematological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Decreased number of reticulocytes in high dose males without signs of anemia and within normal range of the strain used.

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

Several, non dose related statistical variations were seen in differnt groups

Gross pathological findings:

no effects observed

Description (incidence and severity):

red coloured content of digestive tract was considered not adverse.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Other effects:

not examined

Details on results:

According to food consumption, mean substance intakes were as follows:

Males
low dose group 47 mg/kg bodyweight per day
intermediate dose group 227 mg/kg bodyweight per day
high dose group 1172 mg/kg bodyweight per day

Females
low dose group 46 mg/kg bodyweight per day
intermediate dose group 236 mg/kg bodyweight per day
high dose group 1193 mg/kg bodyweight per day

Behaviour and general health condition remained unaffected by the administration of the test compound in all groups. Body weight development, food and water consumption were comparable in all groups.
No signs of neurological disturbances, opacity of the refracting media of the eyes, damage to the oral mucosa or impairment of dental growth were observed in the control or treatment groups.
Hematological and clinical chemistry examinations revealed no abnormalities.
No treatment-related changes were observed by urine analysis.
Organ weights were not affected by the administration of the test compound.
No compound-related effect was observed at necropsy.
The histopathological examinations revealed test compound in the lumen of the alimentary tract, adherent to the surface of the mucous membrane and/or the food. The mucous membranes themselves were uninjured.
In conclusion, Pigment Red 170 caused no detectable adverse effects in male and female Wistar rats when administered via food at the concentration of 12500 mg/kg food for 28 days.
With regard to the present study the 'No Observed Effect Level' is 12500 mg Pigment Red 170 /kg food. This is equivalent to a mean daily compound intake of
1172 mg/kg bodyweight in males and 1193 mg/kg bodyweight in females.

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Remarks on result:

not determinable due to adverse toxic effects at highest dose / concentration tested

Key result

Critical effects observed:

no

Conclusions:

The test item caused no adverse effects after oral exposure for 28 days at doses up to more than 1000 mg/kg bw per day.

Executive summary:

Groups of male and female Wistar rats received Pigment Red 170 at concentrations of 0, 500, 2500 or 12500 mg/kg food for a period of 28 days and were necropsied at day 29.

Behaviour and state of health were observed daily in all groups. Body weights and food consumption were recorded twice weekly and water consumption once weekly.

Hematological examinations, clinical chemistry and urine analysis were carried out at the termination of the study.

During necropsy the animals were examined for macroscopically visible abnormalities, the main organs weighed and the organ to bodyweight ratios calculated.

Many organs and tissues were processed for histopathological examination and checked for microscopically visible changes.

Body weights, hematological and clinical chemistry data, urine data (volume, pH value and specific weight), absolute and relative organ weights were analysed with the aid of a statistical program to show differences compared with the controls.

According to food consumption, mean substance intakes were as follows:

Males - low dose group               47 mg/kg bodyweight per day

intermediate dose group          227 mg/kg bodyweight per day

high dose group                      1172 mg/kg bodyweight per day

Females - low dose group      46 mg/kg bodyweight per day

intermediate dose group        236 mg/kg bodyweight per day

high dose group                          1193 mg/kg bodyweight per day

Behaviour and general health condition remained unaffected by the administration of the test compound in all groups. Body weight development, food and water consumption were comparable in all groups.

No signs of neurological disturbances, opacity of the refracting media of the eyes, damage to the oral mucosa or impairment of dental growth were observed in the control or treatment groups.

Hematological and clinical chemistry examinations revealed no abnormalities. No treatment-related changes were observed by urine analysis.

Organ weights were not affected by the administration of the test compound.

No compound-related effect was observed at necropsy.

The histopathological examinations revealed test compound in the lumen of the alimentary tract, adherent to the surface of the mucous membrane and/or the

food. The mucous membranes itself were uninjured.

In conclusion, Pigment Red 170 caused no detectable adverse effects in male and female Wistar rats when administered via food at the concentration of 12500 mg/kg food for 28 days.

With regard to the present study the 'No Observed Effect Level' is 12500 mg test item / kg food. This is equivalent to a mean daily compound intake of

1172 mg/kg bodyweight in males and 1193 mg/kg bodyweight in females.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 172 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

reliable with acceptable 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

Justification for classification or non-classification

No classification

A subacute study performed using the analogue Pigment Red 170 gave a NOAEL of > 1000 mg/kg bw / day in the rat.