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Administrative data

Description of key information

In an acute oral toxicity study in rats conducted according to OECD test guideline 423, the target substance Zirconium disilicide (99.47% purity) showed no adverse effects at the limit dose of 2000 mg/kg bw. Hence, the LD50 value is considered to be greater than 2000 mg/kg bw.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records
Reference
Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2017-06-28 to 2017-08-29
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Version / remarks:
adopted 17 December 2001
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
acute toxic class method
Limit test:
yes
Specific details on test material used for the study:
TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: In order to get the test item in a solution/suspension, Zirconium disilicide was dissolved in sterile water.
Species:
rat
Strain:
Wistar
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River, 97633 Sulzfeld, Germany
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 8-11 weeks
- Weight at study initiation: Step 1: 176 – 197 g, Step 2: 159 – 171 g
- Fasting period before study: 16 to 19 hours
- Housing: Full barrier in an air-conditioned room; animals were kept in groups in IVC cages, type III H, polysulphone cages on Altromin saw fibre bedding
- Diet (e.g. ad libitum): ad libitum, food: Altromin 1324 maintenance diet for rats and mice
- Water (e.g. ad libitum): ad libitum, water: sulphur acidified to a pH value of approximately 2.8 (drinking water, municipal residue control, microbiological controls at regular intervals)
- Acclimation period: at least 5 days under laboratory conditions

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3
- Humidity (%): 55 +/- 10
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12 / 12
Route of administration:
oral: gavage
Vehicle:
water
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 200 mg/mL
- Justification for choice of vehicle: The vehicle was chosen due to its non-toxic characteristics.
- Lot/batch no. (if required): 612118

DOSE VOLUME APPLIED: 10 mL/ kg body weight

CLASS METHOD (if applicable)
- Starting dose: The starting dose was selected to be 2000 mg/kg body weight
Doses:
2000 mg/kg body weight
No. of animals per sex per dose:
6 females
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days

- Frequency of observations and weighing: Animals were weighed on day 1 (prior to the administration) and on days 8 and 15. Clinical examination was made several times on the day of dosing (at least once during the first 30 minutes and with special attention given during the first 4 hours post-dose). Thereafter, animals were observed for clinical signs once daily until the end of the observation period.

- Necropsy of survivors performed: yes
Statistics:
N.A.
Key result
Sex:
female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Sex:
female
Dose descriptor:
LD0
Effect level:
2 000 mg/kg bw
Based on:
test mat.
Mortality:
No mortality observed
Clinical signs:
No specific findings in any test animal during the whole observation period
Body weight:
No specific findings in any test animal during the whole observation period
Gross pathology:
No specific findings
Other findings:
N.A.
Interpretation of results:
GHS criteria not met
Conclusions:
In an acute oral toxicity study in rats conducted according to OECD 423, no adverse effects were observed for Zirconium disilicide at the limit dose of 2000 mg/kg bw. Hence, the LD50 value is determined to be greater than 2000 mg/kg bw.
Executive summary:

In an acute oral toxicity study (OECD 423), 6 fasted, 8-11 weeks old, female Wistar rats were given a single oral dose of Zirconium disilicide (99.47% purity) in sterile water at the limit dose of 2000 mg/kg bw and were observed for 14 days. All animals survived until the end of the study without showing any test item related signs of toxicity. Throughout the 14-day observation period, the body weight gain of the test animals was within the normal range of variation for this strain. At necropsy, no treatment-related macroscopic findings were observed in any animal of any step. Based on the results from this study, the oral LD50 in rats is considered to be greater than 2000 mg/kg bw.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Quality of whole database:
GLP guideline study

Additional information

In an acute oral toxicity study in rats conducted according to OECD test guideline 423, the target substance Zirconium disilicide (99.47% purity) showed no adverse effects at the limit dose of 2000 mg/kg bw. Hence, the LD50 value is considered to be greater than 2000 mg/kg bw.

Justification for classification or non-classification

Based on the available data, Zirconium disilicide does not warrant classification for acute toxicity in accordance with regulation (EC) No 1272/2008.