Methyl α-D-mannopyranoside

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2021-04-29 to 2021-07-19

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentration: 100 mg/L (limit test)
- The limit concentration and the control were analytically verified in the fresh media at the start of the exposure and at the renewal of the test solutions (0 and 24 hours) as well as in the 24-hours old media at the renewal and at the end of the exposure (24 and 48 hours).
- Sample storage conditions before analysis: All samples were stored at room temperature until the start of the analysis, if necessary. Prepared samples were stored in the autosampler at room temperature until analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Limit test: 100 mg test item/L were freshly prepared with dilution water. The dispersion was agitated until the solution was visually clear.
- Controls: Dilution water without test item
- Evidence of undissolved material: none

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Age at study initiation: Less than 24 hours old daphnids, no first brood progeny was used for the test.
- Culture of animal stock: In glass vessels at 20 ± 2 °C in an incubator, 16 hours illumination; light
intensity of max. 1500 lx, culture medium: Elendt M4, according to OECD 202, Annex 3 (2004)
- Source (Origin): Institut für Wasser-, Boden- und Lufthygiene (WaBoLu), 14195 Berlin, Germany
- Feeding of stock culture: At least 5 times per week ad libitum with a mix of unicellular green algae
- Feeding during test: None

ACCLIMATION
- Acclimatization was not necessary, because the composition of the dilution water is equivalent to the culture medium.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

211 to 250 mg CaCO3/L

Test temperature:

21.3 - 21.6 °C

pH:

7.36 - 7.59

Dissolved oxygen:

7.66 - 8.41 mg/L O2

Salinity:

Not applicable

Conductivity:

Not specified

Nominal and measured concentrations:

nominal: 100 mg test item/L (results are based on nominal concentration)
measured: 99.4 to 106 mg/L (99 to 106 % of nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers (4 (ID) x 7 (H) cm), 50 mL capacity, loosely covered with watch glasses
- Type: closed
- Volume of solution: 20 mL
- Aeration: Not specified
- Renewal rate of test solution: Every 24 hours
- No. of organisms per vessel: 5 daphnids
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4, according to OECD 202, Annex 3 (2004)

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16/8 hours light/dark cycle
- Light intensity: max. 1500 lux

EFFECT PARAMETERS MEASURED: Immobilization was determined in all groups after 24 and 48 hours. An animal was considered immobile, if it was not able to swim in the water phase within 15 seconds after gentle agitation of the test vessel. Observation of other adverse, sub-lethal effects (e.g. discoloration, abnormal behavior etc.) was done, but none occurred during the course of the study.

RANGE-FINDING STUDY
- Test concentrations: 1.0, 10.0 and 100 mg/L
- Results used to determine the conditions for the definitive study: Yes

Reference substance (positive control):

yes

Remarks:

Test performed with potassium dichromate in a separate study.

Duration:

24 h

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks:

immobilisation rate

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks:

immobilisation rate

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks:

immobilisation rate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks:

immobilisation rate

Details on results:

- Behavioural abnormalities: No abnormalities
- Other biological observations: None
- Mortality of control: No mortality
- Other adverse effects control: No
- Immobilisation of control: No immobilisation
- Abnormal responses: No
- Any observations that might cause a difference between measured and nominal values: None
- Effect concentrations exceeding solubility of substance in test medium: No

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Dose-response test: Yes
- EC50: 1.97 mg/L potassium dichromate (95 % confidence limits: 1.00 - 4.00 mg/L)

Table 1: measured concentrations of the test item

Sampling date	0 hours (fresh)		24 hours (aged)		24 hours (fresh)		48 hours (aged)
Nominal test item concentration	Measured conc. [mg/L]	% of nominal	Measured conc. [mg/L]	% of nominal	Measured conc. [mg/L]	% of nominal	Measured conc. [mg/L]	% of nominal
100 mg/L	99.4	99	106	106	105	105	103	103
Control	< LOQ		< LOQ		< LOQ		< LOQ

LOQ (limit of quantification): 10.0 mg test item/L

Table 2: Immobilisation of test animals

Nominal test item concentration	Number of Daphnia tested	Number of immobilised Daphnia
		24 h	48 h
100 mg/L	20	0	0
Control	20	0	0

The EC₅₀ was estimated to be above the tested concentration in the limit test (> 100 mg test item/L).

 

Validity of the test

No immobilisation was observed in the control group. The dissolved oxygen concentration at the end of the test in control and test vessels was more than 3 mg/L in all cases (actual values > 7.36 mg/L). All validity criteria were met, therefore the study is considered to be fully valid.

Validity criteria fulfilled:

yes

Conclusions:

In the acute toxicity test with Daphnia magna according OECD TG 202, the EC50 was estimated to be
above the tested concentration in the limit test (> 100 mg test item/L).

Executive summary:

To investigate the acute toxicity of the test item to aquatic invertebrates, a semi-static immobilisation test with Daphnia magna according to OECD TG 202 was carried out in accordance with GLP principles.
Twenty animals per treatment and control (divided in 4 replicates with 5 animals in each vessel) were exposed in a limit test to the nominal test item concentration of 100 mg/L. For determination of the test item concentrations, samples were taken from the test item treatment group and the control at the start and at the end of each water renewal period, i.e., after 24 hours of exposure. Concentrations were determined by LC-MS/MS. Biological results and endpoints are based on the nominal concentration as the measured concentrations of the test item were within ± 20 % of the nominal value. An untreated control ran in parallel. The immobility or mortality of the Daphnia was determined by visual observation after 24 and 48 hours of exposure. All validity criteria of the test guideline were met. Therefore, the study is considered to be fully valid. No effects of the test item were found. As a result, the EC₅₀ was estimated to be above the tested concentration (> 100 mg test item/L).

Description of key information

In the acute toxicity test with Daphnia magna according OECD TG 202, the EC₅₀ was estimated to be above the tested concentration in the limit test (> 100 mg test item/L) (reference 6.1.3-1).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 100 mg/L

Additional information

To investigate the acute toxicity of the test item to aquatic invertebrates, a semi-static immobilisation test with Daphnia magna according to OECD TG 202 was carried out in accordance with GLP principles.
Twenty animals per treatment and control (divided in 4 replicates with 5 animals in each vessel) were exposed in a limit test to the nominal test item concentration of 100 mg/L. For determination of the test item concentrations, samples were taken from the test item treatment group and the control at the start and at the end of each water renewal period, i.e., after 24 hours of exposure. Concentrations were determined by LC-MS/MS. Biological results and endpoints are based on the nominal concentration as the measured concentrations of the test item were within ± 20 % of the nominal value (99 to 106 % of nominal). An untreated control ran in parallel. The immobility or mortality of the Daphnia was determined by visual observation after 24 and 48 hours of exposure. All validity criteria of the test guideline were met. Therefore, the study is considered to be fully valid. No effects of the test item were found. As a result, the EC₅₀ was estimated to be above the tested concentration (> 100 mg test item/L).