Niobium sulfur tin zinc 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:

05 Dec - 07 Dec 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

adopted in 2004

GLP compliance:

yes (incl. QA statement)

Remarks:

Standards Council of Canada, Ottawa, Canada

Test material

Test material information

Constituent 1

Reference substance name:

niobium oxygen sulfur zinc λ²-stannane

EC Number:

800-035-9

Cas Number:

1374645-21-2

Molecular formula:

Sn1.8Zn0.2Nb2O6.8S0.2 (Sn(2-x)Zn(x)Nb2O(7-y)S(y) with x/2 ≤ y, 0.02 ≤ x ≤ 0.22, 0.01 ≤ y ≤ 0.22)

IUPAC Name:

niobium oxygen sulfur zinc λ²-stannane

Details on test material:

- Name of test material (as cited in study report): EX1455, Niobium Sulfur Tin Zinc Oxide
- Physical state: Solid, yellow powder
- Analytical purity: 100%
- Lot/batch No.: L1903
- Storage condition of test material: At ambient temperature and out of direct sunlight

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: All concentrations were sampled.
- Sample storage conditions before analysis: Samples were preserved using HNO3 for total metals and filtered and preserved using HNO3 for dissolved metals.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Preparation of the test solutions followed OECD’s Guidance Document on Aquatic Toxicity Testing on Difficult Substances and Mixtures (OECD, 2000). A nominal concentration of 100 mg/L was selected as the maximum concentration of the test item to be tested for all range finding and definitive tests. Furthermore, all nominal test solutions were prepared without any vehicle and on the basis of loading rate.
For the range-finding test, a 1 L solution of a 100 mg/L nominal concentration was prepared by adding 0.1004 g of the test item using laboratory dilution water. The solution was stirred for approx. 2.5 h. Non-dissolved solids were visible at this time. Settling for approx. 1 h resulted in a clear solution. The clear supernatant was removed from the volumetric flasks by pipette and used for testing. Lower concentrations including 10, 1 and 0.1 mg/L were prepared on a volume/volume basis by serial dilution in laboratory dilution water.
For the definitive test (limit-test), a 1 L solution of a 100 mg/L nominal concentration was prepared by adding 0.1002 g of the test item using laboratory dilution water. All other procedures related to stirring and settling of the solution were the same as described above.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Waterflea
- Strain: Straus
- Source: Laboratory culture since 1988; originally obtained from the Ministry of the Environment, Toronto, Ontario, Canada
- Age at study initiation (mean and range, SD): Neonates, < 24 h
- Feeding during test: None

ANIMAL HUSBANDRY
- Type and amount of food: Yeast, Cerophyll broth, Trout Chow and Pseudokirchneriella subcapitata/Chlorella fusca algae
- Feeding frequency: Once daily

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Hardness:

210 mg/L CaCO3

Test temperature:

21 - 22 °C

pH:

8.4 - 8.5

Dissolved oxygen:

8.4 - 8.5 mg/L
98 - 100% saturation

Nominal and measured concentrations:

Nominal: 0 and 100 mg/L
Measured (dissolved after 48 h) for nominal 0 mg/L: < LOD (tin, zinc, niobium) and 9.6 - 9.7 mg/L (sulfur)
Measured (dissolved after 48 h) for nominal 100 mg/L: 0.016 - 0.017 mg/L (tin), < LOD (zinc and niobium) and 9.3 - 9.7 mg/L (sulfur)
Measured (total after 48 h) for nominal 100 mg/L: 0.276 - 0.323 mg/L (tin), 0.016 mg/L (zinc), < LOD (niobium) and 9.5 - 9.7 mg/L (sulfur)

Details on test conditions:

TEST SYSTEM
- Test vessel: Beakers
- Material, size, fill volume: Plastic, 250 mL, 100 mL
- Aeration: None
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Groundwater from an aquifer in Aberfoile, Ontario, Canada was filtered through a 20 micron cellulose-acetate filter and diluted with reverse osmosis water to achieve a hardness of 202 mg/L CaCO3.
- Ca/Mg ratio: 1.68/1
- Na/K ratio: 17.6/1
- Conductivity: 466 - 477 µmhos/cm
- Intervals of water quality measurement: Dissolved oxygen, pH and conductivity at test start and test end; temperature and visual observations at 0, 24 and 48 h, dilution water hardness at 0 h.

OTHER TEST CONDITIONS
- Photoperiod: 16 h light/8 h dark, with 30 min transition period
- Light intensity: Ambient laboratory illumination, 400 - 800 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
- Immobilities were observed 24 and 48 h after test start.

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 0, 0.1, 1.0, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: No immobilisation was observed at any concentration.

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

WAF

Basis for effect:

mobility

Remarks on result:

other: Test item solution was allowed to settle after 2.5 h of stirring, supernatant was used for testing.

Details on results:

- Appearance of test solutions: All solutions were clear.
- Mortality of control: No mortalities were observed in the control vessels.
- Effect concentrations exceeding solubility of substance in test medium: Yes