4-(4-nitrophenylazo)-2,6-di-sec-butyl-phenol

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was carried out according to OECD Guideline No. 402 and EEC Directive 84/449/EEC, Part B.3 and in accordance with the Principles of Good Laboratory Practices (GLP).

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Remarks:

Concentration, stability and homogeneity of test substance in vehicle were not determined by analytical procedures

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Remarks:

same as above

Principles of method if other than guideline:

not applicable

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

MORTRACE SB CONC.

IUPAC Name:

MORTRACE SB CONC.

Constituent 2

Reference substance name:

4-(4-Nitrophenylazo)-2,6-di- sec.butylphenol

IUPAC Name:

4-(4-Nitrophenylazo)-2,6-di- sec.butylphenol

Constituent 3

Reference substance name:

4-(4-nitrophenylazo)-2,6-di-sec-butyl-phenol

EC Number:

410-610-2

EC Name:

4-(4-nitrophenylazo)-2,6-di-sec-butyl-phenol

Cas Number:

111850-24-9

Molecular formula:

C20 H25 N3 O3

IUPAC Name:

2,6-bis(butan-2-yl)-4-[2-(4-nitrophenyl)diazen-1-yl]phenol

Test material form:

other: dark red-brown liquid

Details on test material:

- Name of test material (as cited in study report): Mortrace SB Conc.
- Physical state: dark red-brown liquid
- Analytical purity: concentrate
- Lot/batch No.: MR 26592 SBC
- Expiry date: June 03, 1993
- Stability under storage conditions: stable
- Stability in vehicle: stability in corn oil not indicated by the sponsor
- Storage condition of test material: at room temperature protected from light

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: BRL Ltd., basel, Switzerland
- Age at study initiation: approximately 8 weeks
- Housing: individually housed
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days before start of treatment

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21°C
- Humidity (%): 55%
- Air changes (per hr): 15 air changes/hour
- Photoperiod (hrs dark / hrs light): 12 hours light/dark cycle

Administration / exposure

Type of coverage:

occlusive

Vehicle:

corn oil

Details on dermal exposure:

TEST SITE - The formulation was applied to an area of approximately 25 cm2 (5x5 cm) for males and 18 cm2 (3.5x5 cm) for females by application on a gauze patch fixed successively to aluminium foil and flexible bandage (Coban, 3M, St. Paul, U.S.A.), with drops of petrolatum.

REMOVAL OF TEST SUBSTANCE - 24 hours, after exposure residual test substance was removed with a tissue moistened with tap-water.

DOSE LEVEL - 2000 mg/kg body weight

DOSE VOLUME - 10 ml/kg body weight

VEHICLE - corn oil (specific gravity - 0.92)

TEST MATERIAL TREATMENT AND PREPARATION - In order to melt the test substance completely, it was placed for 3 days in a waterbath at 60°C. Chemical analysis (HPLC) of the test substance after melting revealed that the test substance is stable for 3 days at 60°C.
The formulation was prepared immediately prior to dosing. The test substance was heated to maximally 60°C and subsequently weighed into a glass flask on an analytical balance and the vehicle (w/w) was added. The test substance formulation was heated to maximally 60°C to mix the test material. Adjustment was made for specific gravity of vehicle.
Homogeneity of the test substance in vehicle was obtained by using a spatula and by stirring.

Duration of exposure:

24 hours

Doses:

2000 mg/kg body weight

No. of animals per sex per dose:

5 males + 5 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14
- Frequency of observations and weighing: Animals were observed for mortality twice daily and for clinical signs at periodic intervals on the day of application (day 1) and once daily therafter along with the time of onset and duration. Body weights were recorded on days 1 (pre-administration), 8 and 15
- Necropsy of survivors performed: yes

Statistics:

Standard statistical methods were employed

Results and discussion

Preliminary study:

not applicable

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Effect levels 2

Sex:

male/female

Dose descriptor:

LD0

Effect level:

2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred during the study period

Clinical signs:

other: No signs of ill health or behavioural changes were noted in the animals

Gross pathology:

Macroscopic post mortem examination of the surviving animals at termination revealed scab formation in one male.
Yellow/orange appearance of the dorsal and abdominal skin, as noted in all animals, can be attributed to staining properties of the test substance. Therefore, this finding was considered to be of no toxicological significance.
Renal pelvic dilation was noted in one female. As this finding is commonly noted among rats of this age and strain, it was considered not to have arisen as a result of treatment.

Other findings:

Erythema of the treated skin area was noted in one male on days 13 to 15, and scabs were observed in one male and one female during the second week of observation.
The dorsal and abdominal skin was stained yellow/orange by the test substance in all animals from day 2 onwards. No toxicological significance was attached to this finding.

Any other information on results incl. tables

None

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of the study, the dermal LD50 value of MORTRACE SB CONC. in rats of either sex was established as exceeding 2000 mg/kg body weight.

Executive summary:

The purpose of this study was to assess the toxicity of MORTRACE SB CONC. when administered to rats as a single dermal dose. The study was carried out in accordance with OECD Guideline No. 402, “Acute Dermal Toxicity” and EEC Directive 84/449/EEC, Part B.3, “Acute Toxicity — Dermal”. MORTRACE SB CONC. was administered by dermal application, to five rats of each sex, at 2000 mg/kg body weight. Animals were subjected to daily observations and weekly determination of body weight. Macroscopic examination was performed at the end of the experimental period. No animals died during the study. There were no clinical signs of toxicity or behavioural changes noted over the study period. Low body weight gain was noted among the majority of animals over the first week of the observation period. During week 2 of the study, body weight gain by all animals was considered to be similar to that expected of normal untreated animals of the same age and strain. During the second week of the observation period, erythema of the treated skin area was observed in one male, and scabs were noted in one male and one female. Macroscopic post mortem examination of the surviving animals at termination revealed scabs in one male. In the remaining animals, no abnormalities were noted that were not commonly noted among rats of this age and strain or that were considered toxicologically significant. The dermal LD50 value of MORTRACE SB CONC. in rats of either sex was established as exceeding 2000 mg/kg body weight. Based on these results and according to the EEC criteria for classification and labelling requirements for dangerous substances and preparations (EEC Directive 91/325/EEC, Amendment to Annex VI of the EEC Directive 67/548/EEC), M0RTRACE SB CONC. cannot be classified and has no obligatory labelling requirement.