3-methyltetrahydrothiophene 1,1-dioxide

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:

28 August 2018 - 07 September 2018

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:

1992

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Remarks:

UPLC-MS/MS

Details on sampling:

During the test, samples for possible analysis were taken from all test concentrations and the control according to the schedule below.
Frequency at t=0 h, t=24 h and t=96 h
Volume 1.8 mL
Storage Samples were stored in a freezer (≤-15°C) until analysis at the analytical laboratory of the Test Facility.
Additionally, reserve samples of 1.8 mL were taken from all test solutions for possible analysis. If not already used, these samples were stored in a freezer (≤-15°C) for possible analysis for a maximum of three months after delivery of the draft report, pending on the decision of the sponsor for additional analysis

Vehicle:

no

Details on test solutions:

The batch of 3-Methyl Sulfolane tested was a clear colourless to pale yellow liquid and completely soluble in test medium at the concentrations tested. No correction was made for the purity/composition of the test item.
Preparation of test solutions started with the highest concentration of 100 mg/L applying a 15 minute period of magnetic stirring to accelerate dissolution of the test item in test medium. Lower test concentrations were prepared by subsequent dilutions of the highest concentration in test medium. All test solutions were clear and colorless at the end of the preparation procedure.
Any residual volumes were discarded

Test organisms (species):

Cyprinus carpio

Details on test organisms:

- Species: Carp (Cyprinus carpio, Teleostei, Cyprinidae) Linnaeus, 1758
- Source: Zodiac, proefacc, "De Haar Vissen", Wageningen University and Research Centre, The Netherlands.
- Mean length* : Limit test: 3.6 ± 0.2 cm
- Mean weight*: Limit test: 0.57 ± 0.11 g
- Characteristics: F1 from a single parent-pair bred in UV-treated water.
- Reason for selection: This system has been selected as an internationally accepted species.
- Total fish used: 14

*Ten fish of the batch used for the test, were weighed and measured prior to the start of the test.

Holding
- Quarantine/Acclimatisation : At least 12 days after delivery
- Medium: Adjusted ISO medium, formulated using RO-water (tap-water purified by reverse osmosis; GEON Waterbehandeling, Berkel-Enschot, The Netherlands) with the following composition:
CaCl2.2H2O 211.5 mg/L
MgSO4.7H2O 88.8 mg/L
NaHCO3 46.7 mg/L
KCl 4.2 mg/L
- Measurements: Conductivity, pH, nitrate, nitrite and ammonia concentration: once a week. Temperature: continuous. In addition, pH and temperature were measured before transferring the fish to the test system.
- Water quality parameters: Were kept within the optimum limits for the respective fish species.
- Feeding: Daily with pelleted fish food (Essence (300-500 um), Coppens International bv, Helmond, The Netherlands)
- Validity of batch: 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
- Feeding: No feeding from 24 hours prior to the test and during the total test period

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

180 mg CaCO3 per litre

Test temperature:

21- 22 °C

pH:

7.8 - 7.9

Dissolved oxygen:

t(0h) = 8.5 mg/L
t(96h) control = 7.7 mg/L
t(96h) 100 mg/L = 7.8 mg/L

Nominal and measured concentrations:

Nominal: control and 100 mg/L
Measured t=0h, t = 24h, t = 96h
control: < d.l., < d.l., < d.l.
100 mg/L: 99.3, 97.2, 100 mg/L

Details on test conditions:

3-Methyl Sulfolane 100 mg/L, the regulatory limit concentration.
Controls Test medium without test item or other additives.

Test duration 96 hours
Test type Static
Test vessels 20 litres, all-glass, containing 10 litres of test solution.
Test medium Adjusted ISO medium with a hardness of 180 mg CaCO3 per litre and a pH of 7.7 ± 0.3.
Number of fish 7 per concentration
Loading 0.40 g fish/Litre, i.e. 7 fish per 10 litres of test medium
Illumination 16 hours photoperiod daily
Aeration The test media were not aerated during the test.
Feeding No feeding from 24 hours prior to the test and during the total test period
Introduction of fish Within 19 minutes after preparation of the test media from a holding tank with comparable water quality parameters and pH and temperature differences between test and holding tank media of less than 1.0 unit and 1.0°C.

Measurements and Recordings
Mortality and other effects
At 2.5, 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.
Dissolved oxygen content, pH and temperature
Daily in all vessels with surviving fish, beginning at the start of the test (day 0).

Terminal procedures
Euthanasia: At the end of the test the surviving fish were rapidly killed by exposing them to ca. 1.2% ethylene glycol monophenylether in water.

Reference substance (positive control):

yes

Remarks:

pentachlorophenol (PCP)

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:

Samples taken from the control and the limit concentration were analysed. The concentrations measured in the limit concentrations were at the level of the nominal concentration throughout the test, i.e. were 97-100% of the nominal concentration at the start, after 24 hours of exposure and at the end of the test.
Based on these results, the nominal exposure concentrations were used to determine the effect parameters.

No mortality or other clinical effects were observed in the control or the limit concentration throughout the test

Acceptability criteria are met:
1. No mortality was observed in the control at the end of the test.
2. Test conditions were maintained constant throughout the test.
3. The dissolved oxygen concentration has been at least 60% of the air saturation value throughout the test (>5 mg/L at 22°C).
4. The concentrations of the item being tested have been at least 80% of the nominal concentration throughout the test.

Results with reference substance (positive control):

Under the conditions of the test, PCP induced no lethal effects in carp at 0.10 mg/L. The 96h-LC50 for carp exposed to PCP was 0.15 mg/L (95 % confidence interval between 0.10 and 0.22 mg/L). This effect was already reached within 24 hours of exposure.
The range of the 96h-LC50 for carp is generally between 0.10 and 0.46 mg/L based on historical data of reference tests performed approximately every 3 months from April 1988 until the end of 2000, and annually since then. Hence, the sensitivity of carp originating from the present batch for PCP falls within the range of sensitivities generally observed during the past years

Reported statistics and error estimates:

No LC50 could be calculated because the test item proved to be non-toxic (LC50 > maximum concentration).

Validity criteria fulfilled:

yes

Remarks:

see details on results

Conclusions:

No mortality or other clinical effects were observed in the control or the limit concentration throughout the test. In conclusion,the 96h-LC50was beyond the range tested, i.e. exceeded an analytically confirmed nominal concentration of 100 mg/L.

Executive summary:

A test was performed with 3-Methyl Sulfolane in Cyprinus carpio for 96 hours to determine the LC50 according to the OECD 203 guideline and GLP. A limit test was performed under static conditions. Seven carp per test group were exposed to an untreated control and to a nominal concentration of 100 mg/L. The total test period was 96 hours and samples for analytical confirmation of actual exposure concentrations were taken at the start, after 24 hours and at the end of the test period. No mortality or other clinical effects were observed in the control or the limit concentration throughout the test. The concentrations measured in the limit concentrations were at the level of the nominal concentration throughout the test, i.e. were 97-100% of the nominal concentration at the start, after 24 hours of exposure and at the end of the test. The study met the acceptability criteria prescribed by the study plan and was considered valid. In conclusion,the 96h-LC₅₀was beyond the range tested, i.e. exceeded an analytically confirmed nominal concentration of 100 mg/L.

Description of key information

A test was performed with3-Methyl Sulfolane inCyprinus carpiofor 96 hours to determine the LC50 according to the OECD 203 guideline and GLP.A limit test was performed under static conditions. Seven carp per test group were exposed to an untreated control and to a nominal concentration of 100 mg/L. The total test period was 96 hours and samples for analytical confirmation of actual exposure concentrations were taken at the start, after 24 hours and at the end of the test period. No mortality or other clinical effects were observed in the control or the limit concentration throughout the test. The concentrations measured in the limit concentrations were at the level of the nominal concentration throughout the test, i.e. were 97-100% of the nominal concentration at the start, after 24 hours of exposure and at the end of the test. The study met the acceptability criteria prescribed by the study plan and was considered valid.In conclusion,the 96h-LC₅₀was beyond the range 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

Effect concentration:

100 mg/L

Additional information

No mortality or other clinical effects were observed in the control or the limit concentration throughout the test. In conclusion,the 96h-LC50was beyond the range tested, i.e. exceeded an analytically confirmed nominal concentration of 100 mg/L.