[1,3-dihydro-5,6-bis[[(2-hydroxy-1-naphthyl)methylene]amino]-2H-benzimidazol-2-onato(2-)-N5,N6,O5,O6]nickel

Endpoint summary

Description of key information

Acute oral toxicity:

The test item (C.I. Pigment Orange 68) did not cause any mortality or clinical signs after single oral gavage administration to male female rats at 2000 mg/kg bw in a valid guideline study.

Acute inhalation toxicity

No mortality occurred when exposed to a test atmosphere concentration of 5.02 mg/L as a maximum achievable concentration for 4 hours. The acute inhalation median lethal concentration (LC50) of PV Fast Orange 6RL in male and female Crl:WI rats was therefore considered to be above 5.02 mg/L

Acute dermal toxicity:

The substance does not meet the criteria for classification as acutely toxic or STOT SE by the oral route and no systemic effects have been observed in in vivo studies with dermal exposure (column II, Annex VIII, 8.5.3, Regulation (EC) 2016/863)

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

well performed study according to GLP and OECD 423

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

(directive 96/54/EEC)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

other: Hanlbm: WIST (SPF)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: RCC Ltd, Biotechnology & Breeding Division, Füllinsdorf, Switzerland
- Age at study initiation: 9 1/2 weeks
- Weight at study initiation: 213.1 - 218.3 g (males); 163.3 - 171.7 g (females)
- Fasting period before study: 17 h
- Housing: Macrolon cages (type 4) in groups of three
- Diet: peletted standard Kliba 3433 rat maintenance diet (batch no. 04/00, Provimi Kliba AG, Kaiseraugst, Switzerland); ad libitum
- Water: community tap water; ad libitum
- Acclimation period: 7 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22+-3
- Humidity (%): 36 - 57 %
- Photoperiod (hrs dark / hrs light): 12/12
- Air changes (per hr): 10 - 15

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

bi-distilled

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 0.2 g/mL (w/v); mixture was prepared shortly before each dosing
- Application volume: 10 mL/kg bodyweight

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

3 males and 3 females per dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: 1, 2, 3 and 5 hours after administration on day 1; twice daily during days 2 - 15
- Frequency of weighing: on test days 1, 8 and 15
- Necropsy of survivors performed: yes

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: no animals died within the 14 day observation period

Mortality:

no deaths occurred during the study

Clinical signs:

other: moderate to marked orange coloration of faeces was observed for the females from day 2 to 4.

Gross pathology:

animals killed at the end of the observation period showed no macroscopically visible changes

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Single application of the limit dose of 2000 mg test substance per kg bodyweight did not cause lethality in male and female Wistar rats during the 14 day observation period, resulting in a LD50 > 2000 mg/kg bw.

Executive summary:

Male and female rats were treated orally to test acute oral toxicity according to the acute class method (OECD TG 423, limit test). The test substance was administered by gavage at the limit dose of 2000 mg/kg bw to two groups of 3 animals each. Orange discoloured faeces were observed in the group of female animals from day 2 to 4. The body weight development of the animals was within the range commonly recorded for this strain and age. No macroscopic findings were observed at necropsy.

No animal died within the observation period, resulting in a LD50 > 2000 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

reliable without restriction

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:

2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Version / remarks:

2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

traditional method

Limit test:

yes

Species:

rat

Sex:

male/female

Details on test animals or test system and environmental conditions:

Male and female Crl:WI Wistar rats (from SPF colony) were obtained from Charles River Laboratories, Research Models and Services, Germany GmbH (Sandhofer Weg 7,
D-97633 Sulzfeld, Germany).
After arrival, the animals’ health was certified by the Veterinarian.
Species and strain: Crl:WI Wistar rats
Hygienic level: SPF at arrival, standard housing conditions during the study
Number of animals: Sighting Exposure: 1 animal/sex
Main Study: 5 animals/sex
Sex: Male and female, females: non-pregnant and nulliparous
Age and body weight range of animals on the exposure day (Day 0) were:
Sighting Exposure: 8 weeks old, 314 g (males) and 217 g (females)
Main Study: 9 weeks old, 348-372 g (males) and 240-252 g (females

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose only

Vehicle:

air

Mass median aerodynamic diameter (MMAD):

ca. 3.04 - ca. 3.59 µm

Geometric standard deviation (GSD):

ca. 2.42

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

ca. 4 h

Concentrations:

5.02 - 5.06 mg/L

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

guideline study

Statistics:

Data were collected using the software PROVANTIS v.10 or were recorded on data collection sheets taken from the relevant SOPs, then tabulated using PROVANTIS v.10, Microsoft Office Word and/or Excel, as appropriate.

Key result

Sex:

male/female

Dose descriptor:

LC0

Effect level:

ca. 5.02 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Mortality:

none

Clinical signs:

irregular respiration

Remarks:

laboured breathing (slight), fur staining by test item (red, on the cranium, face and whole body) and wet fur (generalized) were observed, but the breathing symptoms could be observed on Days 0-1 only.

Body weight:

no effects

Gross pathology:

no effects

Interpretation of results:

GHS criteria not met

Conclusions:

No mortality occurred when exposed to a test atmosphere concentration of 5.02 mg/L as a maximum achievable concentration for 4 hours. The acute inhalation median lethal concentration (LC50) of PV Fast Orange 6RL in male and female Crl:WI rats was therefore considered to be above 5.02 mg/L

Executive summary:

Crl:WI Wistar strain rats were exposed to test atmosphere of PV Fast Orange 6RL at the target concentration of 5 mg/mL. An atmosphere was generated from the test item as supplied.

A Sighting Exposure was performed first; the target concentration (5 mg/L) was tested on one animal each of both sexes (Group 0.1).

Based on the results of the Sighting Exposure (Group 0.1), the Main Study was performed at the target concentration (5 mg/L). Five male and five female rats were used in the Main Group (Group 1).

In the study, the animals were exposed to the test atmosphere for 4 hours using a nose-only exposure system. Aerosol concentration was measured gravimetrically
17 times during each 4-hour exposure. The particle size distribution of the test aerosol was determined 3 times. The day of exposure was designated as Day 0 followed by a 14-day observation period.

Clinical observations were performed on all animals during exposure at hourly intervals, following removal from restraint, approximately 1 hour after exposure, and daily for 14 days thereafter. Body weight was measured on Days 0 (before the exposure), 1, 3, 7 and 14. Gross necropsy was performed on all animals on Day 14.

No control group was exposed in this study.

The quality of the test atmosphere fully complied with criteria documented in the respective guidelines: OECD 403, EPA OPPTS 870.1300 and Council Regulation (EC) No 440/2008.

The mean achieved atmosphere concentrations in the study were 5.06 and 5.02 mg/L in Group 0.1 and Group 1, respectively. The mass median aerodynamic diameters (MMAD) were 3.59 and 3.04 µm with geometric standard deviations (GSD) of 2.42 and 2.61 in Group 0.1 and Group 1, respectively.

Summary of the test atmosphere parameters

Group Number	Target Concentration (mg/L)	Mean Achieved Concentration (mg/L)	Standard Deviation of Achieved Concentration (mg/L)	MMAD (µm) / GSD
Sighting Exposure
0.1	5	5.06	0.17	3.59 / 2.42
Main Study
1	5	5.02	0.16	3.04 / 2.61

 

 Mortality

No mortality occurred during the study.

Clinical observations

Sighting Exposure (Group 0.1 - 5.06 mg/L)

Laboured breathing (slight to moderate), abnormal breathing sounds, red fur staining (by test item, on the cranium, generalized) and wet fur (generalized) were observed. Fur staining was observed during the whole observation period but the breathing symptoms were observed on Day 0 only.

Main Group (Group 1 - 5.02 mg/L)

In the male animals, laboured breathing (slight), fur staining by test item (red, on the cranium, face and whole body) and wet fur (generalized) were observed, but the breathing symptoms could be observed on Days 0-1 only.

In the female animals, laboured breathing (slight), fur staining by test item (red, on the cranium, face and whole body) and wet fur (on the whole body) were observed, but the breathing symptoms could be observed on Days 0 only.

Wet fur and fur staining in the animals were considered to be related to the restraint and exposure procedures but not to be toxicologically significant.

Summary of acute inhalation toxicity

Group Number	Mean Achieved Concentration (mg/L)	Toxicological Result*	Onset and Duration of Toxicological Clinical Signs (Day)	Occurrence of Mortality (Day)
Sighting Exposure
0.1	5.06	0/ 2/ 2	0	-
Main Study
1	5.02	0/ 10/ 10	0-1	-

* 1^st = number of dead animals, 2^nd = number of animals with signs, 3^rd = number of animals exposed

Body weight

Sighting Exposure (Group 0.1 – 5.05 mg/L)

In one male animal, slight body weight loss was noted on Days 0-1. The body weight gain was normal between Days 1-14.

Main Group (Group 1 – 5.02 mg/L)

Slight body weight loss was recorded on Days 0-1. The body weight gains were normal afterwards.

Necropsy

There was no evidence of any test item-related gross changes at necropsy in any animal.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC0

Value:

5.02 mg/L air

Physical form:

inhalation: dust

Quality of whole database:

reliable

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The LD50 of the test item after a single oral administration to male female rats, observed over a period of 14 days, was greater than 2000 mg/kg body weight. In this study no target organ effects were observed that could be clearly attributed to treatment or that could be clearly presumed to be harmful to human health.

Therefore, the test item has not to be classified as acutely toxic by the oral route (including STOT SE) according to Regulation (EC) No 1272/2008.