Methyl α-D-glucoside

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:

2017-06-22 to 2017-09-22

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:

13 April 2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

30 May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Remarks:

LC-MS

Details on sampling:

- Concentrations: All five test concentrations
- Sample storage conditions before analysis: If analysis could not be applied immediately after sampling, samples were stored under circumstances (-20°C) to maintain the test item stable to the best of knowledge until analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Controls: The control consisted of dilution water only. Four replicates with five specimens per replicate were conducted.
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): no
- Method: The highest test concentration was prepared by adding 100.5 mg of the test item to 1 L dilution water. The solution was stirred using a magnetic stirring bar for about 1 hour at room temperature. The other test concentrations were prepared by serially dilution of the next higher test concentration starting with the highest test concentration of 100.5 mg/L using a spacing factor of 2. The test solutions were freshly prepared prior to test start.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: Daphnia magna
- Source: German Federal Environment Agency, Institut für Wasser-, Boden- und Lufthygiene.
- Age of parental stock (mean and range, SD): at least 3 weeks
- Feeding during test: no


ACCLIMATION
- Acclimation period: adult Daphnids were acclimatised for 1 week
- Acclimation conditions (same as test or not): yes
- Type and amount of food: algal suspension (Desmodesmus subspicatus) and ArtemioFluid (JBL)
- Feeding frequency: Algae growing in the log-phase were centrifuged and the pellet was re-suspended in a few mL of medium. 30 mL of this suspension was given to 1 L Daphnia medium. The water was changed once per week.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

Two Reading intervals: 24h and 48h

Hardness:

total hardness: 1.2 mmol/L

Test temperature:

21.5°C ± 1°C

pH:

8.22 – 8.55

Dissolved oxygen:

8.1 mg/L - 9.0 mg/L

Conductivity:

254 µS/cm

Nominal and measured concentrations:

Nominal: Control, 6.25, 12.5, 25, 50, 100 mg/L
measured: < LOQ, 6.37, 12.9, 23.3, 48.6, 96.1 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers
- Type (delete if not applicable): The beakers were covered with glass panes to prevent from evaporation as much as possible, but also permit gaseous exchange between the medium and the atmosphere and access of light.
- Material, size, headspace, fill volume: Glass, 50 mL nominal volume, fill volume: 50 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: Purified drinking water
- Total organic carbon: NPOC: 0.56 mg/L
- Ca/mg ratio: 2/3
- Conductivity: 254 µS/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: not specified

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod:16h light/8h darkness
- Light intensity: With 853 – 870 lx (corresponding to 11.4 – 11.6 µE/(m² * s)) the light intensity was below the maximum threshold value of about 1000 - 1500 lx (15 - 20 µE/(m² * s))

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobilisation was determined in all groups after 24 and 48 hours.

RANGE-FINDING STUDY
- Test concentrations: 100.0, 10.0 and 1.0 mg/L nominal
- Results used to determine the conditions for the definitive study: In the first nominal test concentration of 1.0 mg/L one daphnid and in the highest test concentration of 100 mg/L four daphnids were found to be dead after 48 hours. However, this effect was not statistically significant. Test concentrations with a spacing factor of 2.0 were used in the definitive test.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

24 h

Dose descriptor:

EC0

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

24 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Mortality of control: 0%

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels:
Immobilisation after 24 h:
Control: 0 %
0.40 mg RS/L: 0 % related to control: 0 %
0.60 mg RS/L: 5 % related to control: 5 %
0.90 mg RS/L: 10 % related to control: 10 %
1.35 mg RS/L: 85 % related to control: 85 %
2.00 mg RS/L: 100 % related to control: 100 %
24 h EC50 value:
Immobilisation: 1.088 mg/L (95% CL :0.63 – 1.84)

Reported statistics and error estimates:

No daphnid died up to and including the highest concentration of 100 mg a.s./L during the study. No mortality was observed in the control or in any the treatments. Therefore, no statistics were performed

Table 1: Effect of the test item on immobilisation of Daphnia magna

Nominal test item concentration [mg/L]	measured test item concentration [mg/L]	Immobilisation%
		24 h					48 h
		Replicates					Replicates
		1	2	3	4	Mean	1	2	3	4	Mean
Control		100	100	100	100	100	100	100	100	100	100
6.25	6.37	100	100	100	100	100	100	100	100	100	100
12.5	12.9	100	100	100	100	100	100	100	100	100	100
25	23.3	100	100	100	100	100	100	100	100	100	100
50	48.6	100	100	100	100	100	100	100	100	100	100
100	96.1	100	100	100	100	100	100	100	100	100	100

Validity criteria fulfilled:

yes

Remarks:

Validity criteria as outlined under "any other information on material and methods" were fulfiled.

Conclusions:

Based on the results LOEC and NOEC are considered to be > 100 mg/L (EC0 = 100 mg/L) and alpha methyl glucoside is not regarded acutely toxic to Daphnia magna under the present experimental conditions.

Executive summary:

The 48–hr-acute toxicity of alpha methyl glucoside to Daphnia magna was studied under static conditions. Daphnids were exposed to control, solvent control, and test chemical at arithmetic mean measured concentrations of 6.37, 12.9, 23.3, 48.6 and 96.1 mg a.s./L, corresponding to 101.9, 103.4, 93.3, 97.1 and 96.1 % of the nominal concentrations for 48 hr. Mortality/immobilization and sublethal effects were observed daily. The 48 – hr NOEC based on mortality and immobilization was > 100 mg a.i./L (EC0 = 100 mg/L). No sublethal effects were observed.

Test Organism Age : 0-24 h

Test Type: Static

 

NOEL> 100 mg a.i./L (EC0 = 100 mg/L)

Endpoint(s) Effected:  None

Description of key information

- OECD guideline study (202), GLP, RL1, LOEC and NOEC > 100 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

In the present study conducted according to OECD guideline 202, each 20 daphnids (Daphnia magna) were incubated with the following nominal concentrations of the test item for 48 h: 0, 6.25, 12.5, 25, 50, 100 mg/L. The analytical verification of the concentrations revealed values which were between 80 and 120% of nominal test concentrations at test start and test end, thus, the evaluation of the concentration-effect-relationships and the calculations of effect concentrations were based on the nominal concentrations of the test item. Based on the results both LOEC and NOEC are considered to be > 100 mg/L and hence the test substance is not regarded acutely toxic to Daphnia magna under the present experimental conditions.