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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Purity/Composition 99.9%

Data source

Reference Type:
study report
Report date:

Materials and methods

Test guidelineopen allclose all
according to guideline
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
according to guideline
EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)
according to guideline
EPA OPPTS 870.1100 (Acute Oral Toxicity)
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.
GLP compliance:
Test type:
acute toxic class method

Test material

Constituent 1
Chemical structure
Reference substance name:
Androsterone tosylate
EC Number:
Cas Number:
Molecular formula:
Androsterone tosylate
Test material form:
solid: particulate/powder
migrated information: powder
Details on test material:
Identification TRANTOS
Molecular formula C26H36O4S
Molecular weight 444.63
CAS Number 10429-07-9
Description White powder (determined at WIL Research Europe
Batch CQE299K1DL2
Purity/Composition 99.9%
Test substance storage At room temperature in the dark
Stability under storage conditions Stable
Expiry date 15 January 2014 (allocated by WIL Research Europe
B.V., 1 year after receipt of the test substance)

Test animals

Details on test animals or test system and environmental conditions:
Species Rat, Wistar strain Crl:WI (Han) (outbred, SPF-Quality). Recognized by international guidelines as the recommended test system (e.g. OECD,EC).
Source: Charles River Deutschland, Sulzfeld, Germany.

Number of animals 9 Females (nulliparous and non-pregnant). Each dose group consisted of 3 animals.
Age and body weight Young adult animals (approx. 8 weeks old) were selected.
Body weight variation did not exceed +/- 20% of the sex mean.
Identification Ear- and tailmark
Health inspection At least upon receipt of the animals and prior to dosing.

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. Any variations to these conditions were maintained in the raw data and had no effect on the outcome of the study.

Group housing of 3 animals per cage in labeled Makrolon cages (MIV type; height 18 cm.) containing sterilized sawdust as bedding material (Litalabo, S.P.P.S., Argenteuil, France) and paper as cageenrichment (Enviro-dri, Wm. Lillico & Son (Wonham Mill Ltd), Surrey, United Kingdom). Acclimatization period was at least 5 days before start of treatment under laboratory conditions.

Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany).

Free access to tap water.

Diet, water, bedding and cage enrichment evaluation for contaminants and/or nutrients was performed according to facility standard procedures. There were no findings that could interfere with the study.

Administration / exposure

Route of administration:
oral: gavage
propylene glycol
Details on oral exposure:
Vehicle: Propylene glycol (Merck, Darmstadt, Germany) (specific gravity 1.036)

Rationale: The vehicle was selected based on trial formulations performed at WIL Research Europe and on test substance data supplied by the sponsor.

Preparation: The formulations (w/w) were prepared within 4 hours prior to dosing. Homogeneity was accomplished to a visually acceptable level. Adjustment was made for specific gravity of the vehicle. No correction was made for purity of the test substance. The concentration of the test substance in vehicle was varied to allow constant dosage volume in terms of mL/kg body weight.

300 mg/kg (10 mL/kg) body weight.
2000 mg/kg (10 mL/kg) body weight.
No. of animals per sex per dose:
stepwise treatment of groups of 3 females
Control animals:
not specified
Details on study design:
The toxicity of the test substance was assessed by stepwise treatment of groups of 3 females. The
first group was treated at a dose level of 300 mg/kg. The absence or presence of mortality of animals
dosed at one step determined the next step, based on the test procedure defined in the guidelines.
The onset, duration and severity of the signs of toxicity were taken into account for determination of
the time interval between the dose groups.
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
Dose descriptor:
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
No mortality occurred.
Clinical signs:
other: Clinical signs observed during the study period were as follows: Dose level Clinical signs 300 mg/kg The animals showed hunched posture, uncoordinated movements and/or piloerection on Day 1. 2000 mg/kg The animals showed lethargy, hunched posture, uncoord
Gross pathology:
No toxicologically relevant abnormalities were found at macroscopic post mortem examination of the
In one animal at 300 mg/kg a diaphragmatic hernia in the left median lobe was noted. This finding is
incidentally seen in these animals of the same age and strain and was therefore considered not
toxicologically significant.

Applicant's summary and conclusion

Interpretation of results:
not classified
Migrated information Criteria used for interpretation of results: EU
The oral LD50 value of TRANTOS in Wistar rats was established to exceed 2000 mg/kg body weight.
Executive summary:

The oral LD50 value of TRANTOS in Wistar rats was established to exceed 2000 mg/kg body weight. Based on these results: - according to the Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures, TRANTOS does not have to be classified and has no obligatory labelling requirement for oral toxicity.