Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
18 April - 04 May 2012
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2012
Report Date:
2012

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 870.1100 (Acute Oral Toxicity)
Deviations:
no
Qualifier:
according to
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

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
semi-solid (amorphous): gel
Remarks:
migrated information: paste
Details on test material:
- Name of test material (as cited in study report): C.I. Leuco Sulphur Brown 37
- Substance type: Dark brown paste
- Physical state: Paste
- Storage condition of test material: At room temperature in the dark
- Volatile: No
- Reactivity: Reactive to oxygen, risk of oxidation in contact with air
- Test substance handling: Avoid long exposure to air
- pH (1% in water, indicative range): 8.8 - 8.4

Test animals

Species:
rat
Strain:
other: Wistar strain, Crl:WI (Han)
Sex:
female
Details on test animals and environmental conditions:
- Source: Charles River Deutschland, Sulzfeld, Germany.
- Age at study initiation: Young adult animals (approx. 8 weeks old)
- Weight at study initiation: Body weight variation was within +/- 20% of the sex mean (150-168 grams)
- Fasting period before study: Animals were deprived of food overnight prior to dosing and until approximately 1 hour after the second 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: 18 April - 04 May 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.

VEHICLE: 1% Aqueous carboxymethyl cellulose
- Justification for choice of vehicle: The vehicle was selected based on trial formulations performed at NOTOX and on test substance data supplied by the sponsor.

MAXIMUM DOSE VOLUME APPLIED: 20 mL/kg b.w. per dosage

DOSAGE PREPARATION: The formulations (w/w) were prepared within 5 hours prior to dosing. Homogeneity was accomplished to a visually acceptable level. Correction was made for purity of the test substance.
Doses:
2000 mg/kg body weight, by administration of two times 1000 mg/kg (20 ml/kg) b.w., due to the low purity of the test substance.

No. of animals per sex per dose:
6
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: On the day of dosing (Day 1): immediately after the first dose (t=0; both groups)), and approximately 2 hours (t=2; both groups) and approximately 5 hours (t=5) after the first dose of the first group of females or approximately 4 hours (t=4) after the first dose of the second group of females. The t=4/t=5 observation was conducted approximately 30-50 minutes after the second dose.
From Days 2-15: once daily.
- 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
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 all animals after dosing on Day 1.
This transient finding may have been due to the high application volume necessary to achieve the limit dose.
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:
practically nontoxic
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The oral LD50 value of C.I. Leuco Sulphur Brown 37 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.
Executive summary:

Assessment of acute oral toxicity with the test material in the rat (Acute Toxic Class Method) was carried out based on the guidelines described in:

OECD No.423 (2001) "Acute Oral Toxicity, Acute Toxic Class Method"

Commission Regulation (EC) No 440/2008, B1 tris: "Acute Oral Toxicity, Acute Toxic Class Method"

The test material w

as 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).

Results:

No mortality occurred.

Hunched posture was shown by all animals after dosing on Day 1.

The body weight gain shown by the animals over the study period was considered to be normal.

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

The oral LD50 value of the test material 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.

Final