Magnesium potassium titanium oxide

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 October 2000-02 May 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study has been performed according to OECD and EC guidelines and according to GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Version / remarks:

(1992)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

(1992)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

436-900-9

EC Name:

-

Cas Number:

39290-90-9

Molecular formula:

Hill Empirical formula: K(0.2-0.7) Mg(0.4) Ti(1.6) O(3.7-3.95) CAS Empirical formula: K(0.2-0.7) Mg(0.4) Ti(1.6) O(3.7-3.95)

IUPAC Name:

Magnesium Potassium Titanium Oxide

Details on test material:

Batch: 0G99
White powder
Expiry date: 21 August 2001
Test substance storage: At room temperature in the dark

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 (control) and 100 mg/L nominal (filtered and unfiltered)
- Sampling method: 10 mL from the approximate centre of the test vessels
- Sample storage conditions before analysis: in a deep freeze until shipment to Solvias AG, Basel, Switzerland.

Test solutions

Vehicle:

no

Details on test solutions:

Supersaturated solutions were prepared at nominally 100 mg/L and magnetically stirred for three days to achieve maximum solubility. Then, two of the solutions were filtered through a paper filter to remove the larger undissolved test substance particles (ca. > 5 µm). The filtered solution was used to prepare three lower concentrations (0.1, 1 and 10% of the filtrate) . The other solution was not filtered and used as such (100 mg/L nominal).

The unfiltered solution was a turbid whitish dispersion with undissolved test substance particles. The undiluted filtered solution was slightly turbid, while the dilutions of the filtrate were clear and colourless.

Test organisms

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: Carp
- Strain: Cyprinus carpio, Teleostei, Cyprinidae
- Source: Zodiac, proefacc, "De Haar Vissen", L.U. Wageningen, the Netherlands.
- Length at study initiation (length definition, mean, range and SD): 2.14 ± 0.12 cm
- Weight at study initiation (mean and range, SD): 0.24 ± 0.05 g
- Method of breeding: F1 from a single parent-pair bred in UV-treated water.
- Feeding during test: No feeding from 48 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): yes
- Type and amount of food: Trouvit
- 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%.

NUMBER OF FISH
100 mg/l filtered and unfiltered and control: 7 fish per test group.
dilutions: 3 fish per test group.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test conditions

Hardness:

250 mg CaCO3/L

Test temperature:

Blank control: 20.8 (day 0) - 21.0 (day 4)
100% filtrate: 20.9 (day 0) - 20.5 (day 4)
100 mg/l: 20.6 (day 0) - 20.5 (day 4)

pH:

Blank control: 8.0 (day 0) - 7.6 (day 4)
100% filtrate: 8.9 (day 0) - 7.7 (day 4)
100 mg/l: 9.0 (day 0) - 7.8 (day 4)

Dissolved oxygen:

Blank control: 9.3 (day 0) - 7.6 (day 4) mg/l
100% filtrate: 7.4 (day 0) - 7.4 (day 4) mg/l
100 mg/l: 9.0 (day 0) - 7.7 (day 4) mg/l

Nominal and measured concentrations:

A filtered and unfiltered solution prepared at nominally 100 mg/l and dilutions of the filtrate containing 0.1, 1.0 and 10% filtrate.
Blank-control Test medium without test substance or other additives (0 mg/l).

Analysis of the samples taken from the unfiltered test solution showed that the titanium concentration measured in the water phase decreased during the test period from 19420 µg/l to 28 µg/l after 96 hours. This was due to precipitation and deposition of the undissolved test substance particles. The concentration measured in the filtered test solution decreased from 2688 µg/l to 146 µg/l during the test period. This could be due to the fact that filtration had not been complete. Hence, measured concentrations in both the filtered and unfiltered solution remained above the calculated water solubility (< 10 µg/l based on titanium corresponding with < 36 µg/l for TERRACESS P).

Details on test conditions:

The test media were not aerated during the test.
16 hours photoperiod daily
Loading: 100 mg/L filtered and unfiltered and control: 0.34 g fish/L, i.e. 7 fish per 5 litres of test medium. Dilutions: 0.24 g fish/L, i.e. 3 fish per 3 litres of test medium.

Reference substance (positive control):

yes

Remarks:

pentachlorophenol

Results and discussion

Effect concentrations

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 417 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

element

Remarks:

titanium

Basis for effect:

mortality (fish)

Details on results:

During the 96-hour test period no visible effects were observed in any of the concentrations tested. The test substance induced no visible effects in carp when exposed to a filtered or an unfiltered solution prepared at 100 mg/L. Owing to the extremely poor solubility of the test substance in water, concentration levels toxic for fish could not be reached.  Therefore, the 96h-LC50 for Carp exceeded the maximum solubility of TERRACESS P in water at a loading of 100 mg/L, the regulatory limit concentration.

Results with reference substance (positive control):

The 96h-LC50 for carp exposed to the reference substance was already reached after 48 hours of exposure and was 0.14 mg/L with a 95 % confidence interval between 0.13 and 0.18 mg/L.

Reported statistics and error estimates:

The range of the 96h-LC50 for carp is generally between 0.10 and 0.46 mg/L based on historical data.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The calculated 96h-LC50 for Carp is > 1417 ug/L. This is an avearge of the measured Ti concentrations in the filtered test solutions that decreased from 2866 ug/L to 146 ug/L during the test period. The calculated 96h-LC50 is 5141 ug Terraces P/L.