Cerium terbium magnesium undecaaluminum nonadecaoxide (hexagonal) ((Ce, Tb)MgAl11O19) and aluminium oxide (Al2O3) from calcination of Al2O3, CeO2, MgO and Tb4O7

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 November 2011 - 03 December 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

Adopted 17 July, 1992

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Version / remarks:

Adopted 30 May 2008

Qualifier:

according to guideline

Guideline:

ISO 7346-1 (Determination of the Acute Lethal Toxicity of Substances to a Freshwater Fish [Brachydanio rerio Hamilton-Buchanan (Teleostei, Cyprinidae)] - Part 1: Static Method)

Version / remarks:

Adopted 1996-06-15

Qualifier:

according to guideline

Guideline:

other: Guidance document on aquatic toxicity testing of difficult substances and mixtures, OECD series on testing and assessment number 23, December 14, 2000

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Samples for possible analysis were taken from all test concentrations and the control at t=0 h, t=24 h and t=96 h (volume 4.8 ml). In addition, the filter used for the preparation of the highest test concentration was retained for possible analysis of the residue. The samples were stored in the freezer (≤ -15°C).On the day of analysis, the samples were defrosted at room temperature and diluted in a 24:1 (v/v) ratio with HNO3.
Additionally, reserve samples of 4.8 ml were taken from all test solutions for possible analysis. If not already used, these samples were stored in a freezer for a maximum of three months after delivery of the draft report, pending on the decision of the sponsor for additional analysis.

Vehicle:

no

Details on test solutions:

Preparation of test solutions started with aquatic mixtures prepared individually at loading rates of 1.0, 10 and 100 mg/l. The mixtures were treated with ultrasonic waves for 10 minutes and then magnetically stirred for two days. The resulting dispersions were filtered through a 0.45 μm membrane filter (Whatman; RC55) to remove the remaining undissolved material. The resulting filtrates were all clear and colourless.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: Carp
- Source: Zodiac, proefacc, "De Haar Vissen", Wageningen University and Research Centre, The Netherlands.
- Length at study initiation (length definition, mean, range and SD): 2.4 ± 0.1 cm
- Weight at study initiation (mean and range, SD):0.35 ± 0.08 g
- Method of breeding: F1 from a single parent-pair bred in UV-treated water.
- Feeding during test: No feeding from 24 hours prior to the test and during the total test period


ACCLIMATION
- Acclimation period: at least 12 days after delivery
- Acclimation conditions (same as test or not): same as test
- Type and amount of food: pelleted fish food (Cyprico Crumble Excellent (300-500 um), Coppens International bv, Helmond, The Netherlands)
- Feeding frequency: daily
- Health during acclimation (any mortality observed): In the batch of fish used for the test, mortality during the seven days prior to the start of the test was less than 5%.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

none

Hardness:

180 mg CaCO3/L

Test temperature:

21.3-22.2°C

pH:

7.4 - 8.0

Dissolved oxygen:

6.1 - 9.5
Oxygen levels had dropped to 5.8-5.9 mg/l after 78 hours of exposure. Aeration was introduced and maintained until the end
of the test

Salinity:

Not applicable.

Nominal and measured concentrations:

Nominal: 1, 10 and 100 mg/L
Measured: No detectable concentrations of Al were present during the 96-hour exposure period. Concentrations of Ce and Tb were detectable and stable during the test period with measured concentration of 2.7 μg Ce/l and 13 μg Tb/l at the start and 2.4 μg Ce/l and 12 μg Tb/l after 96 hours of exposure (means: 2.6 μg Ce/l and 12 μg Tb/l).

Details on test conditions:

TEST SYSTEM
- Test vessel: Control and highest test concentration: 9 litres, all-glass, containing 9 litres of test solution; Both lower test concentrations: 5 litres, all-glass, containing 4 litres of test solution.
- Aeration: Aeration was introduced after 78 hours of exposure and was maintained until the end of the test.
- No. of organisms per vessel: 7 each for the control and the highest test concentration; 3 each for both lower test concentrations.
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1

Medium:
Adjusted ISO medium, formulated using RO-water (tap-water purified by reverse osmosis) with the following composition:
CaCl2.2H2O 211.5 mg/l
MgSO4.7H2O 88.8 mg/l
NaHCO3 46.7 mg/l
KCl 4.2 mg/l

OTHER TEST CONDITIONS
- Photoperiod: 16 hours photoperiod daily

Reference substance (positive control):

yes

Remarks:

Pentachlorophenol (PCP)

Key result

Remarks on result:

other: The 96h-LC50 was determined to be > maximum soluble concentration in test medium.

Details on results:

The 96h LC50 was determined to be > maximum soluble concentration in test medium.
No mortality or other visible effects were observed in any of the groups.
Due to the very low solubility in test medium, concentration levels toxic for Carp could not be reached.

Results with reference substance (positive control):

The 96h-LC50 for carp exposed to PCP was estimated to be 0.15 mg/l (95 % confidence interval between 0.10 and 0.22 mg/l). This effect was already reached within 24 hours of exposure.
The range of the 96h-LC50 for carp is generally between 0.10 and 0.46 mg/l based on historical data of reference tests performed approximately every 3 months from April 1988 until the end of 2000, and annually since then. Hence, the sensitivity of carp originating from the present batch for PCP falls within the range of sensitivities generally observed during the past years.

Validity criteria fulfilled:

yes

Conclusions:

CAT induced no visible effects in carp at a concentration obtained in a filtered solution prepared at a loading rate of 100 mg/l. The 96h-LC50 exceeded the concentration present in a filtered solution prepared at a loading rate of 100 mg/l, which was considered the maximum soluble concentration in the test medium.

Description of key information

CAT was tested in a 96h acute toxicity study in carp (OECD 203). The substance induced no visible or lethal effects in carp in a 0.45 μm filtered solution prepared at a loading rate of 100 mg/L.

Additional information

CAT was tested in a 96h acute toxicity study in carp (OECD 203). The substance induced no visible or lethal effects in carp in a 0.45 μm filtered solution prepared at a loading rate of 100 mg/l. The 96h-LC50 exceeded the concentration present in a 0.45 μm filtered solution prepared at a loading rate of 100 mg/l, which was considered the maximum soluble concentration in test medium.