Phenol, 4-(phenylamino)-, sulfurized, leuco deriv.

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 - 22 November 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), 12 Nohsan, Notification No 8147, April 2011, including the most recent partial revisions.

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

phenol, 4-(phenylamino)-, sulfurised, leuco deriv.

Molecular formula:

not applicable

IUPAC Name:

phenol, 4-(phenylamino)-, sulfurised, leuco deriv.

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

- Source: Charles River Deutschland, Sulzfeld, Germany.
- Age at study initiation: Young adult animals (approx. 8-9 weeks old)
- Weight at study initiation: Body weight variation was within +/- 20% of the sex mean (first group: 169 - 188 grams; second group: 159-167 grams).
- Fasting period before study: Animals were deprived of food overnight prior to dosing and until 3-4 hours after administration of the test substance. Water was available ad libitum.
- Housing: Group housing of 3 animals per cage in labeled Macrolon cages
- Diet: Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany).
- Water: Free access to tap water.
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
Environmental controls for the animal room were set to maintain 18 to 24°C, a relative humidity of 40 to 70%, approximately 15 room air changes/hour, and a 12-hour light/12-hour dark cycle.

IN-LIFE DATES: From: 02 to 22 November 2012

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Details on oral exposure:

GAVAGE METHOD: plastic feeding tubes.

Frequency:
Two dosages within 24 hours. The first on t=0 and the second on t=4 hours. Multiple dosages given within 24 hours are regarded as a single dose (see also dose volume).

The maximum time between formulation and the second dosing on each day was exceeded with a maximum of approximately 0.75 hours.

Fasting:
Animals were deprived of food overnight prior to dosing and until approximately 2 hours after the second administration of the test substance. Water was available ad libitum.

The maximum time of fasting of 24 hours was exceeded with 2 minutes for the second group at 2000 mg/kg.

VEHICLE
- Justification for choice of vehicle: The vehicle was selected based on trial formulations performed at WIL Research Europe and on test substance data supplied by the sponsor.

MAXIMUM DOSE VOLUME APPLIED: 2000 mg/kg (10 mL/kg) body weight.

DOSAGE PREPARATION:
The formulations (w/w) were prepared within 5 hours or within approximately 5.75 hours prior to the first and second dosing on each day, respectively. Homogeneity was accomplished to a visually acceptable level. Correction was made for purity of the test substance (16.4%).

Doses:

2000 mg/kg body weight

No. of animals per sex per dose:

6 (2 groups of three females in a stepwise manner)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
Mortality/Viability: Twice daily
Body weights: Days 1 (pre-administration), 8 and 15.
Clinical signs: At periodic intervals on the day of dosing (Day 1) and once daily thereafter, until Day 15.
- Necropsy of survivors performed: At the end of the observation period, all animals were sacrificed by oxygen/carbon dioxide procedure and subjected to necropsy. Descriptions of all internal macroscopic abnormalities were recorded.
- Other examinations performed: none.

Statistics:

No statistical analysis was performed (The method used is not intended to allow the calculation of a precise LD50 value).

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred.

Clinical signs:

Hunched posture was shown by three animals on Day 1.

Black faeces noted for both groups at 2000 mg/kg between Days 2 and 4, was considered to be related to staining properties of the test substance (a black paste).

Body weight:

The body weight gain shown by the animals over the study period was considered to be similar to that expected of normal untreated animals of the same age and strain.

Gross pathology:

No abnormalities were found at macroscopic post mortem examination of the animals.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In an acute oral toxicity study with female rats, performed according to OECD 423 guidelines, an LD50 of >2000 mg/kg bw was determined.

Executive summary:

In an acute oral toxicity study, the test substance was administered by oral gavage to two subsequent groups of three female Wistar rats at 2000 mg/kg body weight. The total dose was administered as two dosages of 1000 mg/kg body weight each (the first on t=0 and the second on t=4 hours), due to the low purity of the test substance. Animals were subjected to daily observations and weekly determination of body weight. Macroscopic examination was performed after terminal sacrifice (Day 15).

Hunched posture was shown by three animals on Day 1. Black faeces noted for both groups at 2000 mg/kg between Days 2 and 4, was considered to be related to staining properties of the test substance (a black paste). The body weight gain shown by the animals over the study period was considered to be normal. No mortality occurred and no abnormalities were found at macroscopic post mortem examination of the animals.

The oral LD50 value in Wistar rats was established to exceed 2000 mg/kg body weight.

According to the OECD 423 test guideline, the LD50 cut-off value was considered to exceed 5000 mg/kg body weight.