Short Chain Fructo Oligosaccharides

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:

08 Jul 2022 - 19 Jul 2022

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)

Specific details on test material used for the study:

Identification: Actilight 950P Premium "Fructo-Oligosaccharides"
Substance: Short-chain fructo-oligosaccharides
EC No.: 908-300-1
Appearance: White powder
Purity: 95.4%

COMPOSITION:
scFOS is short chains of fructose molecules linked to a molecule of sucrose (glucose-fructose disaccharide). Thus, scFOS is a multiconstituent substance composed of three oligosaccharides: 1-kestose (GF2), nystose (GF3) and fructosyl-nystose (GF4).
With:
- TOTAL FOS: 95.4 expressed as dry matter
- Kestose (GF2): 39.2% FOS
- Nystose (GF3): 47.6% FOS
- 1F-Fructofuranosylnystose (GF4:) 13.6% FOS
- Glucose +Fructose + Saccharose : 4.6% expressed as dry matter

Analytical monitoring:

yes

Details on sampling:

Samples for possible analysis (2.0 mL) were taken from the limit concentration and the control at t=0 and t=96 hours.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The batch of Fructo-oligosaccharides tested was a white powder with a purity of 95.4% and was visually completely soluble in test medium at the concentration tested. No correction was made for the purity/composition of the test material. Preparation of test solution started with the limit concentration of 100 mg/L. No other treatment than vigorous shaking was needed to completely dissolve the test material in medium. The test solution was clear and colorless at the end of the preparation procedure.
- Controls: Test medium without test material or other additives.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: common or Eurasian carp
- Strain: n/a
- Source: ‘De Haar Vissen’, Zodiac proefacc. Wageningen University & Research, The Netherlands.
- Length at study initiation (mean and SD): 2.0 ± 0.1 cm
- Weight at study initiation (mean and SD): 0.15 ± 0.02 g
- Method of breeding: F1 from a single parent-pair bred in UV-treated water

ACCLIMATION
- Acclimation period: At least 12 days after delivery
- Acclimation conditions: Same as test conditions
- Type of food and frequency of feeding during acclimation: Daily with pelleted fish food (Essence 0.2-0.3 mm, Coppens International B.V., Helmond, The Netherlands) until at the latest 24 hours before the start of exposure)
- Health during acclimation: In the batch of fish used for the test, mortality during the seven days prior to the start of the test was less than 5%.

FEEDING DURING TEST
- No feeding from 24 hours prior to the test and during the total exposure period.

TERMINAL PROCEDURES
- At the end of the test the surviving fish were rapidly euthanized by exposing them to ca. 1.2% ethylene glycol monophenylether in water.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

180 mg CaCO3/L

Test temperature:

21°C

pH:

7.4 - 7.9

Dissolved oxygen:

Control: 7.1 - 8.2 mg/L
Limit concentration: 7.2 - 8.1 mg/L

Nominal and measured concentrations:

Nominal: 100 mg/L
Measured: 104 mg/L at test start, 107 mg/L at test end. Based on these results, effect parameters are expressed as (analytically confirmed) nominal concentrations.

Details on test conditions:

TEST SYSTEM
- Test vessel: 6.5 liters, all-glass, containing 5.0 liters of test solution
- Aeration: no aeration during the test
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.21 g fish/liter, i.e. 7 fish per 5.0 liters of test medium

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: tap water purified by reverse osmosis, with added salts
- Culture medium different from test medium: no, same
- Intervals of water quality measurement: dissolved oxygen content, pH and temperature were measured daily in all vessels, beginning at day 0. Temperature was additionally continuously measured in a temperature control vessel, beginning at the start of the test.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod and light intensity: 16 hours photoperiod daily with a light intensity ranging between 171 - 201 lux.

EFFECT PARAMETERS MEASURED
- Mortality and other effects were measured at 3, 24, 48, 72 and 96 hours following the start of exposure. In addition, every afternoon from day 0 to observe for any dead or severely distressed fish. Dead fish were removed when observed.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: not applicable, limit test at 100 mg/L.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

Analytical results:
See Table 1 for details. The measured concentration at the start of the test was 104 mg/L in the limit concentration. During the exposure period, the concentration remained stable, i.e. was at 103% relative to initial at the end of the test (107 mg/L). No test material was detected in the samples taken from the control. Based on these results, effect parameters were expressed as analytically confirmed nominal concentrations.

Biological results:
See Table 2 for details. All test conditions remained within the ranges prescribed by the study plan. No mortality or sublethal effects were observed in the control and at the limit concentration throughout the exposure period. The responses recorded in this test allowed for the conclusion that the LC50 lies beyond the limit concentration tested, i.e. exceeded a nominal concentration of 100 mg/L.

Reported statistics and error estimates:

No LC50 could be determined because observed effects were below 50% as the test material proved to be non-toxic to carp (Cyprinus carpio) (LC50 > maximum concentration tested).

Sublethal observations / clinical signs:

Table 1: Measured concentrations

Time of sampling [hours]	Concentration [mg/L]		Relative to nominal [%]	Relative to initial [%]
	Nominal	Analyzed
0	0	<LOQ ^1	n.a.
	100	104	104
96	0	<LOQ ^1	n.a.	n.a.
	100	107	107	103

¹: The analyzed concentration is below limit of quantification (LOQ) of 0.1 mg/L

 

Table 2: Mortality

Fructo-oligosaccharides Nominal conc. (mg/L)	Initial Number of fish	Cumulative mortality					Total Mortality (%)
		3h	24h	48h	72h	96h
Control	7	0^1	0^1	0^1	0^1	0^1	0
100	7	0^1	0^1	0^1	0^1	0^1	0

¹ No sublethal effects were observed.

Validity criteria fulfilled:

yes

Remarks:

See 'Overall remarks' for details on validity criteria.

Conclusions:

The 96h-LC50 for carp (Cyprinus carpio) exposed to Fructo-oligosaccharides was beyond the limit concentration tested, i.e. exceeded an analytically confirmed nominal concentration of 100 mg/L

Executive summary:

The toxicity of the ScFOS to the carp (Cyprinus carpio) was investigated in a GLP-compliant study performed in accordance with OECD Guideline No. 203.

A limit test was performed. In this limit test, 7 fish (1 replicate) were exposed to the nominal concentrations of 100 mg/L under static conditions during 96 hours. A control of 7 fish was also performed. An analytical monitoring was carried out at t=0 and t= 96 hours.

As a results, the concentration of the limit test concertation remained stable, i.e. was at 103% relative to initial at the end of the test. Based on these results, effect parameters were expressed as analytically confirmed nominal concentrations.

No mortality or sublethal effects were observed in the control and at the limit concentration throughout the exposure period.

In conclusion, the 96h-LC50 for carp (Cyprinus carpio) exposed to ScFOS was beyond the limit concentration tested, i.e. exceeded an analytically confirmed nominal concentration of 100 mg/L.

Description of key information

The toxicity of the ScFOS to the carp (Cyprinus carpio) was investigated in a GLP-compliant study performed in accordance with OECD Guideline No. 203.

Under the test conditions, no mortality or sublethal effects were observed in the control and at the limit concentration throughout the exposure period. The 96h-LC50 for carp (Cyprinus carpio) exposed to ScFOS was beyond the limit concentration tested, i.e. exceeded an analytically confirmed nominal concentration of 100 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

> 100 mg/L

Additional information

The toxicity of the ScFOS to carp (Cyprinus carpio) magna was investigated in one GLP-compliant study performed in accordance with standard methods, without deviations. The study is considered as reliable (Klimisch 1) and is selected as a key study for the endpoint.