Xanthylium, 3,6-bis(diethylamino)-9-[2-(ethoxycarbonyl)phenyl]-, molybdatetungstatephosphate

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 September 2017 - 01 March 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

EU Method C.20 (Daphnia magna Reproduction Test)

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch: 280PE310516
Purity: UVCB (treat as 100%)
Storage Conditions: Room temperature in the dark

Analytical monitoring:

yes

Details on sampling:

- Concentrations:
range-finding test: 1.0, 10 and 100 mg/L.
Definitive test: 0.056, 0.10, 0.18, 0.32 and 0.56 mg/L

- Sampling method: A sample of each test concentration was taken for chemical analysis on Days 0 and 3 in order to determine the stability of the test item under test conditions
- Sample storage: All samples were stored frozen prior to analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Due to the low aqueous solubility and complex nature of the test item, for the purposes of the study the test medium was prepared as a Water Accommodated Fraction (WAF) of the test item.
- Controls: identical conditions but not exposed to the test item

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: daphnia magna
- Strain/clone: 1st instar
- Justification for species other than prescribed by test guideline: Daphnia magna is a freshwater invertebrate representative of a wide variety of natural habitats, and can therefore be considered as an important non-target organism in freshwater ecosystems.
- Source: in house cultures
- Age of parental stock (mean and range, SD): 24 hours
- Food type: fed daily with a mixture of algal suspension (Desmodesmus subspicatus) and Tetramin® flake food suspension

ACCLIMATION
- Acclimation period: 24 hours
- Acclimation conditions (same as test or not): same

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Remarks on exposure duration:

not specified

Post exposure observation period:

not specified

Hardness:

248 to 290 mg/L as CaCO3

Test temperature:

19°C - 21°C

pH:

7.7 - 8.0

Dissolved oxygen:

≥7.7 mg O2/L

Salinity:

not specified

Conductivity:

not specified

Nominal and measured concentrations:

nominal

Details on test conditions:

TEST SYSTEM
- Test vessel: 150 mL glass vessels
- Type (delete if not applicable): closed
- Aeration: not aerated
- Renewal rate of test solution (frequency/flow rate): three times per week on Days 0, 2, 5, 7, 9, 12, 14, 16 and 19
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): For each test and control group 10 replicate test vessels

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted Water – Elendt M7 Medium
- Culture medium different from test medium: same
- Intervals of water quality measurement: Measurements were made on one replicate for each test concentration, once per week

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light and 8 hours darkness with 20 minute dawn and dusk transition periods for 21 days
- Light intensity: not exceeding 1500 Lux

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 1.0, 10 and 100 mg/L., 0.010, 0.10 and 1.0 mg/L.
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

no

Key result

Duration:

21 d

Dose descriptor:

NOELR

Effect conc.:

ca. 0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Key result

Duration:

21 d

Dose descriptor:

LOELR

Effect conc.:

ca. 0.18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Key result

Duration:

21 d

Dose descriptor:

EL50

Effect conc.:

ca. 0.11 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

immobilisation

Key result

Duration:

21 d

Dose descriptor:

EL50

Effect conc.:

ca. 0.13 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Details on results:

- Behavioural abnormalities:
- Observations on body length and weight: length, no differences statistically
- Mortality of control: 0%
- Effect concentrations exceeding solubility of substance in test medium: no

Results with reference substance (positive control):

not specified

Reported statistics and error estimates:

95% confidence limits

Validity criteria fulfilled:

yes

Conclusions:

Exposure of Daphnia magna to the test item resulted in significant mortalities at the loading rates of 0.18, 0.32 and 0.56 mg/L resulting in 90%, 100% and 100% mortalities by Day 4.
The 21-Day EL50 (immobilization) value, based on nominal loading rates, for the parental daphnia generation (P1) was calculated to be 0.11 mg/L with 95% confidence limits of 0.080 – 0.15 mg/L.
The 21-Day EL50 (reproduction) based on nominal loading rates was 0.13 mg/L with 95% confidence limits of 0.096 – 0.15 mg/L.
The Lowest Observed Effect Loading Rate and the No Observed Effect Loading Rate based on nominal loading rates were 0.18 and 0.10 mg/L respectively.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.1 mg/L