Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP compliant guideline study, available as unpublished report, no restrictions, fully adequate for assessment.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2006
Report Date:
2006

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Qualifier:
according to
Guideline:
EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)
Qualifier:
according to
Guideline:
EPA OPPTS 870.1100 (Acute Oral Toxicity)
GLP compliance:
yes (incl. certificate)
Remarks:
BASF AG experimental toxicology and ecology
Test type:
acute toxic class method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of the test substance used in the study report: 1,2,3,4-Tetrahydroisoquinoline
- Purity: 87.3 area-% (analytical report No.: 05L00222)
- Test substance number: 05/0797-1
- Batch number: LJ 32741/75
- Homogeneity: The test substance was homogeneous by visual inspection
- Stability: The stability under storage conditions over the study period was guaranteed by the sponsor

Test animals

Species:
rat
Strain:
Wistar
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: RCC Ltd Laboratory Animal Services, Wölferstrasse 4, CH-4414 Füllinsdorf, Switzerland
- Reasons for selection of the test species: Rats were selected since this rodent species is recommended in the respective test guidelines. Wistar rats were selected since there is extensive experience available in the Iaboratory with this strain of rats
- Age and weight at study initiation: 8-12 weeks, 172-182 g
- Sex: As suggested by the OECD guideline nulliparous and nonpregnant female animais were used for the test, because there is no indication that male animais are Iikely to be more sensitive to the acute effects of the test substance
- Identification: Individual identification by cage cards and tail marking
- Fasting period before study: 16 hours
- Housing: single housing in stainless steel wire mesh cages, type DK-III (Becker&Co., Castrop-Rauxel, FRG)
- Diet: Kliba-Labordiät (Maus / Ratte Haltung "GLP"), Provimi Kliba SA, Kaiseraugst, Basel, Switzerland, ad libitum
- Water: tap water ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24;
- Humidity (%): 30-70;
- Air changes (per hr): fully air-conditioned;
- Photoperiod (hrs dark / hrs light): 12/12 (6.00 am - 6.00 pm / 6.00 pm - 6.00 am);

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
olive oil
Details on oral exposure:
VEHICLE
- Olive oil Ph.Eur./DAB
- Concentration in vehicle: 1 or 6 g/100mL;
- Amount of vehicle (if gavage): 5 mL/kg;
- Justification for choice of vehicle: Inhomogeneous in aqueous preparations;

DOSAGE PREPARATION:
The test substance preparation was produced for each administration group shortly before administration by stirring with a magnetic stirrer.

ANALYTICAL VERIFICATION:
- Correctness of the concentration of the test substance in the test preparation was confirmed by analysis (once, in the first preparation for the 300 mg/kg bw group).
- Stability of the test substance in the vehicle was confirmed indirectly by analysis of the correctness of the concentration.
- The test substance preparation was visually homogeneous (solution).
Doses:
50 and 300 mg/kg
No. of animals per sex per dose:
6
Control animals:
no
Details on study design:
- Route of administration: Single oral administration by gavage.
- Fasting period: Feed was withdrawn from the animals at least 16 hours before administration, but water was available ad libitum.
- Time of day of administration: In the morning.
- Observation period: At least 14 days.
- Body weight determination: Individual body weights shortly before administration (day 0), weekly thereafter and at the end of the study. Additionally, at day of death in animals that died starting with study day 1.
- Signs and symptoms: Recording of signs and symptoms several times on the day of administration, at least once each workday for the individual animals; these records are maintained with the raw data.
- Mortality: A check for any dead or moribund animal was made twice each workday and once on Saturdays, Sundays and on public holidays.
- Pathology: Necropsy with gross-pathology examination on the last day of the observation period after killing by CO2-inhalation. Necropsy of all animals that died before as early as possible after death.

Results and discussion

Effect levels
Sex:
female
Dose descriptor:
LD50
Effect level:
ca. 300 mg/kg bw
Based on:
test mat.
Mortality:
One animal of the first 300 mg/kg administration group and two animals of the second 300 mg/kg administration group were found dead on study day 1, respectively. No mortality occurred in the 50 mg/kg administration groups.
Clinical signs:
Clinical observation in the 300 mg/kg administration groups revealed impaired and poor general state, dyspnoea, staggering, ataxia, rolling convulsions, opisthotonus, extention spasm, tonic convulsions, piloerection, smeared fur, diarrhea, salivation, lacrimation, chromodacryorrhea and red clammy snout and eyelid and were observed from hour 0 through to study day 6 after administration.
Clinical observation in the 50 mg/kg administration groups revealed impaired general state, dyspnoea, piloerection, smeared fur and diarrhea and were observed from hour 1 through to hour 5 after administration.
Body weight:
The mean body weights of the surviving animais of the administration groups increased throughout the study period.
Gross pathology:
The following macroscopic pathologic findings were observed in the animals that died (dose group 300 mg/kg (3 females)): a few black erosions/ulcers in the glandular stomach (diameter up to 5 mm) and a black discoloration of the contents in the small intestine.
The following macroscopic pathologic abnormality was noted in the surviving animal of the second 300 mg/kg administration group: a few black erosions/ulcers in the glandular stomach (diameter 2 mm).
No macroscopic pathologic abnormalities were noted in the animals of the 50 mg/kg administration groups (6 females) and in 2 animals of the first 300 mg/kg administration group examined at termination of the study.
Other findings:
lmmunohistochemistry for tyrosine hydroxylase (specific marker to reveal dopaminergic neurons and their synaptic end terminals) of all animals of the first 300 mg/kg administration group and of the two animals that died of the second 300 mg/kg administration group revealed a slight decrease of staining intensity in the corpus striatum of forebrain sections indicating the possibility of a diminished dopamine content in this target location of dopaminergic neurons. Further pathological changes (e.g. necrotic neurons) were not detected in this first and limited, morphological examination of two brain levels.

Applicant's summary and conclusion