4-[[2-methoxy-4-[(4-nitrophenyl)azo]phenyl]azo]phenol

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Start of experimental phase: 23 March 2017 End of experimental phase: 07 April 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

adopted on 24 February 1987

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: EPA, OPPTS Methods 870.1000 “Acute Toxicity Testing - Background”

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4-[[2-methoxy-4-[(4-nitrophenyl)azo]phenyl]azo]phenol

EC Number:

243-325-5

EC Name:

4-[[2-methoxy-4-[(4-nitrophenyl)azo]phenyl]azo]phenol

Cas Number:

19800-42-1

Molecular formula:

C19H15N5O4

IUPAC Name:

4-[[2-methoxy-4-[(4-nitrophenyl)azo]phenyl]azo]phenol

Test material form:

solid: particulate/powder

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
Species and strain: Rat, Hsd: Sprague Dawley SD
Sex: Males and females (nulliparous and non-pregnant)
Age: 6 to 8 weeks old
Weight at order: 176 to 200 grams
Supplier: Envigo RMS s.r.l., San Pietro al Natisone (UD), Italy
Breeder: Envigo RMS B.V., Kreuzelweg 53, 5961 NM Horst, Netherlands
Date of arrival: 15March 2017
Weight range at arrival: 188 to 193 grams for males; 189 to 197 grams for females
Acclimatisation period: At least 5 days
Veterinary health check: During acclimatisation period

ENVIRONMENTAL CONDITIONS
Animals per cage: Up to 5 of one sex during acclimatisation; individually caged
during the study
Housing: Clear polysulphone H-Temp solid bottomed cages (Tecniplast Gazzada S.a.r.l., Buguggiate, VA, Italy) measuring 59.5×38×20 cm during acclimatisation period and 42.5×26.6×18.5 cm
during the study with nesting material provided into suitable bedding bags.
Cage control: Daily inspected and changed as necessary (at least 3 times/week)
Water Drinking: water supplied to each cage via a water bottle
Water supply: Ad libitum
Diet: 4 RF 18 (Mucedola S.r.l., Via G. Galilei, 4, 20019, Settimo Milanese (MI) Italy)
Diet supply: Ad libitum throughout the study
Room lighting: Artificial (fluorescent tubes), daily light/dark cycle of 12/12 hours
Air changes: Approximately 15 to 20 air changes per hour
Temperature range: 22°C±2°C
Relative humidity range: 55%±15%

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

water

Remarks:

pasted with 1.5 mL water

Details on dermal exposure:

TEST SITE
- Area of exposure: Dorsal surface of the trunk
- % coverage: Approximately 10% of body surface
- Type of wrap if used: Adhesive bandage and gauze patch

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Yes, with cotton wool soaked with lukewarm water
- Time after start of exposure: 24 hours

Duration of exposure:

The animals remained in contact with the test item for 24 hours

Doses:

2000 mg/kg body weight

No. of animals per sex per dose:

5 males and 5 females at 2000 mg/kg body weight

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were observed for clinical signs the day of dosing: on dosing, approximately 1 hour after dosing, 2 hours after dosing and 4 hours after dosing, aaily thereafter. All animals were weighed at allocation to the study (Day -1), on the day of dosing (Day 1) and on Days 8 and 15.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight.

Statistics:

NA

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD0

Effect level:

>= 2 000 mg/kg bw

Based on:

test mat. (total fraction)

Remarks on result:

no indication of skin irritation up to the relevant limit dose level

Mortality:

No mortality occurred.

Clinical signs:

other: Only black staining at the treated site, due to the colour of the test substance, was observed in all male and female animals from Day 2 up to Day 7. This discolouration recovered from Day 8 up to Day 14 of the observation period.

Gross pathology:

No abnormalities were found at necropsy examination performed on all animals at termination of the study.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The acute toxicity of Disperse Orange 29 was investigated following dermal administration of a single dose to the rat at 2000mg/kg body weight.
No mortality occurred following dosing and no signs of toxicity were observed during the 14-day observation period.
These results indicate that the test item, Disperse Orange 29, has no toxic effect on the rat following dermal exposure over a 24 hour period at a level of 2000 mg/kg body weight. The lack of mortality demonstrates the LD50 to be greater than 2000mg/kg body weight.
European Directives concerning the classification, packaging and labelling of dangerous substances (Council Regulation (EC) No. 1272/2008 and subsequent revisions) would suggest the following:
Classification No category
Signal word No signal word required
Hazard statement No hazard statement required

Executive summary:

The acute toxicity of Disperse Orange 29 following dermal administration of a single dose to the rat was investigated according to OECD test guideline 402. For that purpose, a single dose of 2000 mg/kg body weight was administered to a group of 5 male and 5 female animals for 24 hours. After 14 days of observation, all animals were killed and subjected to necropsy examination.

No mortality occurred and no signs of toxicity were observed in male or female animals during the observation period. The body weight changes observed during the study were within the expected range for this species and age of animals.

No abnormalities either general or at the treated site were found at necropsy in the animals at termination of the study. These results indicate that the test item, Disperse Orange 29, has no toxic effect on the rat following dermal exposure over a 24 hour period at a level of 2000mg/kg body weight. The lack of mortality demonstrates the LD50 to be greater than 2000 mg/kg body weight.