reaction mass of neodymium carbonate and praseodymium carbonate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28-MAR-2013 to 19-AUG-2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted in compliance with GLP and according to the OECD guideline 423.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

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

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

reaction mass of neodymium carbonate and praseodymium carbonate

Molecular formula:

(Nd,Pr)2 (CO3)3

IUPAC Name:

reaction mass of neodymium carbonate and praseodymium carbonate

Constituent 2

Reference substance name:

937-221-5

IUPAC Name:

937-221-5

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Janvier, Le Genest-Saint-Isle, France
- Age at study initiation: 8 weeks old on the day of treatment
- Weight at study initiation: 198 to 219 g (mean bodyweight of 208 g)
- Fasting period before study: Overnight before treatment for food only
- Housing: 3 from the same group/polycarbonate cage with stainless steel lids (Techniplast 2154.940 cm²) containing autoclaved sawdust (SICSA, Alfortville, France)
- Diet: Ad libitum, SSNIFF R/M-H pelleted maintenace diet (SSNIFF Spezialdiäten GmbH, Soest, Germany)
- Water: Ad libitum, tap water filtered using a 0.22-µm filter
- Acclimation period: At least 5 days before treatment
- Other: Nulliparous and non-pregnant

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2°C
- Humidity (%): 50 ± 20%
- Air changes (per hr): 12 cycles/hour of filtered, non-recycled air
- Photoperiod (hrs dark / hrs light): 12 h/12 h (light: 7h-19h)

IN-LIFE DATES: From 13-MAY-2013 to 04-JUN-2013

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 0.5% methylcellulose aqueous solution

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg
- Justification for choice of vehicle: A homogeneous solution of test material was obtained at the concentration of 200 mg/mL in 0.5% methylcellulose aqueous solution.
- Lot/batch no. (if required): 079K0054
- Purity: The 0.5% methylcellulose was prepared in drinking water treated by reverse osmosis using ELIX 5 (Millipore SA).

DOSAGE PREPARATION (if unusual): The dose formulation was stirred for at least 10 min prior to its administration to the animals and then continuously throughout the dosing procedure.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: Based on available test material toxicity data (from separated OECD 420 studies with neodymium carbonate and praseodymium carbonate components) no morbidity or mortality was expected to occur at the dose-level of 2000 mg/kg. This was therefore chosen as the starting dose-level.

Doses:

2000 mg of active ingredient/kg bodyweight (nominal conc.)

The test item concentration was corrected to take into account the water content of the test item by a correction factor of 1.577. Thus, the active ingr. concentration of 2000 mg/kg corresponds to 3124 mg of test item/kg.

No. of animals per sex per dose:

3 per group

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Mortality and morbidity of each animal were checked frequently during the hours following administration, then at least once a day until the end of the observation period, including weekends and public holidays. The body weight of each animal was recorded on the day of allocation of the animals into groups then on the day of treatment (i.e. day 1) and on days 8 and 15.
- Necropsy of survivors performed: Yes (on completion of the observation period)
- Other examinations performed: Clinical signs (at least once during the first 30 min, periodically during the first 4 h, then once a day for a total of 14 days, at approximately the same time), body weight, macroscopic post-mortem examination (digestive tract, heart, kidneys, liver, lungs, pancreas, spleen and any other organs with obvious abnormalities)

Statistics:

not included

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

act. ingr.

Remarks:

(correction factor due to water content: 1,577)

Remarks on result:

other: no deaths

Mortality:

No unscheduled deaths occurred during the study for both groups of females.

Clinical signs:

other: No clinical signs were observed in any animals for both groups of females.

Gross pathology:

There were no findings considered to be related to the test item administration.

Any other information on results incl. tables

- BODY WEIGHTS:

 

Sex	Females
Group Dose-level (mg/kg bw)	Historical control data 0	1 2000	2 2000
Body weight (mean ± SD) [g] day -1 day 1 day 8 day 15	226 (± 10.9) 208 (± 11.7) 246 (± 12.7) 266 (± 14.0)	236 (± 3.6) 215 (± 3.5) 258 (± 5.1) 274 (± 5.6)	220 (± 6.9) 200 (± 3.2) 243 (± 2.1) 254 (± 9.3)
Body weight change (mean ± SD) [g] day 1-8 day 8-15 day 1-15	+39 (± 11.7) +20 (± 6.3) +58 (± 5.8)	+43 (± 1.5) +16 (± 0.6) +59 (± 2.0)	+42 (± 0.6) +11 (± 8.7) +53 (± 7.9)

SD: standard deviations

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the experimental conditions of this study, the oral LD50 of the test item, Reaction mass of neodymium carbonate and praseodymium carbonate, was higher than 2000 mg/kg bw in rats. Therefore, the test item is not classified as toxic by the oral route according to the criteria of CLP Regulation.

Executive summary:

The objective of this study was to evaluate the potential acute toxicity of the reaction mass of neodymium carbonate and praseodymium carbonate, following a single oral administration (gavage) to rats according to OECD guideline 423 and in compliance with GLP.

 

Prepared in 0.5% methylcellulose, the test item was administered once at the starting dose-level of 2000 mg (as active ingredient) /kg body weight (bw) by the oral route (gavage) to two groups of three fasted female Sprague-Dawley rats under a dosage-volume of 10 mL/kg. Each animal was observed at least once a day for mortality and clinical signs for 15 days. Body weight was recorded on day 1 and then on days 8 and 15. On completion of the observation period, the animals were sacrificed and then submitted to a macroscopic post-mortem examination.

 

No unscheduled deaths and no clinical signs were observed in any animals during the study for both groups of females. Body weight gain was unaffected by the test item treatment compared to historical control data. Moreover, no test item-related macroscopic findings were observed.

 

In conclusion, under the experimental conditions of this study, the oral LD50 of the test item, reaction mass of neodymium carbonate and praseodymium carbonate, was higher than 2000 mg/kg bw in female rats. Therefore, the test item is not classified as toxic by the oral route according to the criteria of Directive 67/548/EEC (DSD), Regulation (EC) No. 1272/2008 (CLP) and UN GHS.