Methyl α-D-mannopyranoside

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2021-06-29 to 2021-08-12

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

2019

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentration: 100 mg/L (limit test)
- Sampling method: The Limit concentration and the control were analytically verified in
the fresh media at the start of exposure and at the renewal of the test solutions (0 and 72 hours) as well as in the 24-hours old media at the renewal and at the end of the exposure (24 and 96 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. An appropriate amount of the test item was weighted out and transferred into a test vessel filled with an appropriate amount of the dilution water. The test media was mixed with an ultraturrax (1 min, 17000 rpm). This procedure was repeated for every water renewal.
- Controls: Dilution water without test item
- Evidence of undissolved material: none

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: zebrafish
- Source: Umweltbundesamt, Schichauweg 58, D-12307 Berlin, Germany, brood stock maintained at test facility
- Age at study initiation: juvenile
- Average length at study end: 1.79 cm
- Average weight at study end: 0.067 g

ACCLIMATION
- Acclimation period: at least 9 days
- Acclimation conditions: same as test
- Type of food during acclimation: Sera Vipan (SERA GMBH, 52518 Heinsberg, Germany)
- Feeding frequency during acclimation: Food was provided 3 times per week. Food was given to satisation (4 % of the fish body weight) per feeding day. The test fish were not fed 24 h before test start.
- Health during acclimation: Healthy, no mortality observed

FEEDING DURING TEST: None

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

Not applicable

Hardness:

67 mg/L

Test temperature:

22.8 - 23.5 °C

pH:

7.46 - 7.91

Dissolved oxygen:

95 - 100 % oxygen saturation

Salinity:

Not applicable

Conductivity:

183 μS/cm

Nominal and measured concentrations:

Nominal: 100 mg/L (results are based on nominal concentration)
Measured: 88.3 - 105 mg/L (88 to 105 % of nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass aquaria of 13 L were used, filled with approximately 10 L of dilution water (dimensions: 25.5/18/28 cm, depth of water: approx. 20 cm) and covered with glass plates
- Type: closed
- Test volume: 10 L per test vessel
- Aeration: No
- Renewal rate of test solution: Every 24 hours
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.047 g fish/L

TEST MEDIUM / WATER PARAMETERS
- Dilution water: Tap water of local origin. The water was filtered on activated charcoal and aerated for at least 24 h to remove chlorine.
- Chlorine: < 0.01 mg/L
- Total organic carbon: < 2 mg/L
- Total Hardness: 67 mg/L
- Acidity: 0.2 mmol/L
- Alkalinity: 0.8 mmol/L
- Conductivity: 183 μS/cm
- Culture medium different from test medium: No

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: light/dark cycle: 16/8 h
- Light intensity: 741 to 787 Lux

EFFECT PARAMETERS MEASURED: Mortality, all vessels with living fish inspected twice per day

TEST CONCENTRATIONS
- Range finding study: No
- Test concentrations: 100 mg/L
- Results used to determine the conditions for the definitive study: Concentration based on the derivation of a threshold concentration (TC) from an algae toxicity test (ErC50 (0-72 h) > 100 mg/L) and a daphnia toxicity (EC50 (0-48 h) > 100 mg/L).

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Other abnormalities: None
- Mortality of control: No
- 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

Sublethal observations / clinical signs:

Table 1: Measured concentration of the test item during the test 

Sampling date	0 hours (fresh)		24 hours (aged)		72 hours (fresh)		96 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	102	102	88.3	88	105	105	104	104
Control	< LOQ		< LOQ		< LOQ		< LOQ

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

 

Table 2: Cumulative mortality

Nominal test item concentration	Cumulative mortality [%] at observation time [hours]
	Day 0		Day 1		Day 2		Day 3		Day 4
	2 h	4 h	23 h	28 h	47.5 h	54 h	70 h	77 h	95 h	96 h
100 mg/L	0	0	0	0	0	0	0	0	0	0
Control	0	0	0	0	0	0	0	0	0	0

The LC₅₀ was estimated to be above the tested concentration in the limit test (> 100 mg test item/L).

 

Validity:

The study was performed according to the OECD-Guideline No. 203 (2019) for Testing of Chemicals and GLP principles and met the validity criteria:
- The O₂ saturation should be > 60 % (this study: ≥ 95 %).
- The mortality in the control group should not exceed 1/7 fish (this study: 0/7 fish).
- Recovery rates of the test item were 80 - 120 % throughout the test.

 

Validity criteria fulfilled:

yes

Conclusions:

In the 96-hour toxicity test on zebrafish (Danio rerio) according to OECD TG 203, the LC50 was higher than the tested concentration in the limit test (> 100 mg/L).

Executive summary:

An experimental study was conducted according to OECD 203 and GLP under semi-static conditions as limit test. The limit test was performed with the nominal concentration of 100 mg/L test item. The test concentration was analysed by LC-MS/MS from fresh and aged test solutions. The effect concentrations were based on the nominal concentration as the measured concentrations of the test item were within ± 20 % of the nominal value. 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 and after 96 h no mortality was observed. Thus, the LC₅₀ (96 h) was estimated to be > 100 mg/L (nominal).

Description of key information

In the 96-hour toxicity test on zebrafish (Danio rerio) according to OECD TG 203, the LC₅₀ was higher than the tested concentration in the limit test (> 100 mg/L) (reference 6.1.1-1).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

> 100 mg/L

Additional information

One experimental study was conducted according to OECD 203 and GLP under semi-static conditions as limit test. The limit test was performed with the nominal concentration of 100 mg/L test item. The test concentration was analysed by LC-MS/MS from fresh and aged test solutions. The effect concentrations were based on the nominal concentration as the measured concentrations of the test item were within ± 20 % of the nominal value. 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 and after 96 h no mortality was observed. Thus, the LC₅₀ (96 h) was estimated to be > 100 mg/L (nominal).