Magnesium potassium titanium oxide

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

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 the appropriate ISO and 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:

ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))

Version / remarks:

(1996)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

(1992)

Test guideline 3

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

(1984)

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

Test material form:

solid

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:

- samples for analysis were taken from the blank-control and the filtered (100% filtrate) and unfiltered (100 mg/l nominal) solutions
- Sampling method: 10 mL from the approximate centre of the test vessels
- Frequency: at the start and the end of the test (t=48 h)
- 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. 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%). The third solution was not filtered and used as such (100 mg/L nominal).

The unfiltered solution (100 mg/L nominal) was a turbid whitish dispersion with undissolved test substance particles.
The undiluted filtered solution (100% filtrate) was slightly turbid, while the dilutions of the filtrate were clear and colourless.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: In-house laboratory culture with a known history
- Age at study initiation: < 24 hours.
- Method of breeding: With newborn daphnids, i.e. less than 3 days old, by placing about 250 of them into 10 litres of medium in an all-glass culture vessel
- Feeding during test: no feeding

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

No post exposure observations

Test conditions

Hardness:

250 mg CaCO3/L

Test temperature:

20.5-21.4°C

pH:

8.0-9.0

Dissolved oxygen:

7.4-9.3 mg/L

Nominal and measured concentrations:

Measured concentrations of Terracess P (calculated from the measured Titanium concentrations)

Blank control: below the limit of quantification

100% filtrate: 69912 µg/L (t=0) - 54/644 µg/L (t=48) (duplicate measurements)

100 mg/l nominal : 9677 µg/L (t=0) - 97 µg/L (t=48)

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 ml, all-glass
- Aeration: no aeration of the test solutions
- No. of organisms per vessel: 10 per vessel containing 80 ml of the solution
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Adjusted ISO medium
- Culture medium different from test medium: yes for culturing M7 medium is used

OTHER TEST CONDITIONS
- Adjustment of pH: 8.0 ± 0.2
- Photoperiod: 16 hours daily

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobility (including mortality) daily

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10
-Test concentrations: 0, 0.1, 1, 10 and 100% of the filtrate + 100 mg/l nominal (not filtered)

TEST:
The study was a combined limit/range finding test

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 23 536 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

element

Remarks:

titanium

Basis for effect:

mobility

Details on results:

No immobility was observed in the control or any of the test concentrations.

Results with reference substance (positive control):

- Results with reference substance valid: Yes
- Mortality after 48h: 0% at 0.10 mg/L; 0% at 0.18 mg/L; 0% at 0.32 mg/L; 0% at 0.56 mg/L; 100% at 1.0 and 1.8 mg/L
- 48h-EC50 was 0.75 mg/l with a 95% confidence interval between 0.56 and 1.0 mg/L

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the test, Terracess P did not induce acute immobilisation of Dapnia magna at a loading rate of 100 mg/L after 48 h of exposure. Due to the very low solubility of Terracess P in water, concentration levels that might be toxic for daphnids could not be reached. Hence the 48 h-EC50 for Daphnia exceeded the maximum solubility of the substance in water. The EC50 exceeds 23536 ug/L based on Ti analysis that corresponds to an EC50 of 85397.84 ug Terraces P/L.