Bis(dodecylthio)dimethylstannane

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not specified

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Restriction: No analytical confirmation of exposure concentrations.

Reason / purpose for cross-reference:

other: read-across target

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Details on sampling:

not applicable

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A single 1,000 mg/L WAF was prepared for the test. The WAF was formulated by combining 1.0 g of test material and 1 litre of dilution water in a plastic mixing vessel equipped with a magnetic stirrer. The mixture was stirred for approximately 24 hours (vortex was approximately 25 % of media depth) and allowed to settle for approximately 1 hour. Following the settling period the water phase containing the WAF was removed from the mixing vessel with a siphon using care to exclude any material on the surface, bottom, or sides of the mixing vessel. Test media was prepared at 0.10, 1.0, 10, 100, and 1,000 mg/L by combining the appropriate volume of the 1,000 mg/L WAFG and dilution water.
- Controls: deionised dilution water
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): 0.10, 1.0, 10, 100, 1,000 mg/L
- Evidence of undissolved material (e.g. precipitate, surface film, etc): The 1,000 mg/L WAF was slightly cloudy throughout the test. No other insoluble material was noted during the test.

Test organisms (species):

Daphnia magna

Details on test organisms:

- Common name: water flea
- Strain: daphnia magna
- Source: Procured from a commercial supplier Aquatic Research Organisms, Hampton, New Hampshire on June 1, 1994
- Age at study initiation: Daphnids were Juveniles less than 24 hours old
- Weight at study initiation: Average 0.44 mg
- Method of breeding: The daphnids were produced by adult daphnids that were maintained under test conditions at TR. Wilbury facility for more than 7 days.
- Feeding during test
- Food type: Daphnids were not fed during the test.


ACCLIMATION
- Acclimation period: Seven days.
- Type and amount of food: Daphnids were provided with the freshwater alga, Selenastrujm capricornutum, and a yeast/trout chow mixture daily throughout the acclimation period.
- Feeding frequency: ad libitum
- Health during acclimation: During acclimation daphnids were not treated for disease and they were free of apparent sickness, injuries, and abnormalities at the beginning of the test (no mortality occurred during the 48 hours before the start of the test).

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

not applicable

Hardness:

160 mg/L as CaCO3

Test temperature:

19.9 - 20.9°C

pH:

8.0 - 8.6

Dissolved oxygen:

8.4 - 9.1 mg/L

Nominal and measured concentrations:

nominal: 0.10, 1.0, 10, 100, and 1000 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 300 mL beakers that contained 250 mL of test solution
- Type: Vessels were loosely covered during the test.
- Fill volume: 300 mL
- Aeration: None
- Type of flow-through (e.g. peristaltic or proportional diluter): Static
- Renewal rate of test solution (frequency/flow rate): None
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): Single
- No. of vessels per control (replicates): Single
- No. of vessels per vehicle control (replicates): NA
- Biomass loading rate: Approximately 0.018 g/L.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Water used for acclimation of test organisms and for all toxicity testing was deionised. Water was adjusted to a hardness of 160 mg/L as CaCO3 and stored in 500 gallon polyethylene tanks where it was aerated and continuously passed through a particle filter, ultraviolet steriliser, and activated carbon.

- Total organic carbon: 1 mg/L
- Particulate matter: No data
- Metals: all non detect; iron 0.03 mg/L
- Pesticides: non detect
- Chlorine: non detect
- Alkalinity: no data
- Ca/mg ratio: no data
- Conductivity: 600 to 650 µmhois/cm
- Culture medium different from test medium: No
- Intervals of water quality measurement: 24 hour intervals

OTHER TEST CONDITIONS
- Adjustment of pH: no range was 8.0 to 8.6
- Photoperiod: 16 hour’s light/8 hours dark
- Light intensity: Ambient laboratory lighting


EFFECT PARAMETERS MEASURED: mortality and sublethal effects recorded initially and after 24 and 48 hours


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10 %
- Range finding study
- Test concentrations: Control, 0.10, 1.0, 10, 100 and 1,000 mg/L by combining the appropriate volume of the 1,000 mg/L WAF and dilution water.
- Results used to determine the conditions for the definitive study: This test is a range finding test.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% CL 10 to 100 mg/L

Details on results:

- Behavioural abnormalities: none
- Observations on body length and weight: no data
- Other biological observations: immobility
- Mortality of control: one hundred percent survival occurred in the control and no control sublethal effects were noted during the test.
- Other adverse effects control: none
- Abnormal responses: immobility
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: The 1,000 mg/L WAF was slightly cloudy throughout the test. No other insoluble material was noted during the test.
- Effect concentrations exceeding solubility of substance in test medium: The 1,000 mg/L WAF was slightly cloudy throughout the test. No other insoluble material was noted during the test.

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

Data were evaluated using the binomial/non-linear interpolation method (Stephan 1983). The NOEC was defined as the highest concentration tested that allowed at least 90 % survival and did not cause sublethal effects.

Control (0 mg/L): 100 % survival
0.10 mg/L: 100 % survival
1.0 mg/L: 100 % survival
10 mg/L: 100 % survival
100 mg/L: 20 % survival
1000 mg/L: 0 % survival

Validity criteria fulfilled:

yes

Conclusions:

Exposure of the aquatic invertebrate, Daphnia magna, to the test material resulted in a 48-h EC50 of 32 mg/L and a NOEC of 10 mg/L based on immobility and survival.

Executive summary:

The acute toxicity of the test material to the daphnid, Daphnia magna, was investigated in accordance with the standardised guideline OECD 202, under GLP conditions. The test was performed under static conditions with the WAF of 0.10, 1.0, 10, 100 and 1000 mg/L mixtures of test material and water.

Under the conditions of the study, the 48 hour median effective concentration (EC50) of the WAF to daphnids wast determined to be 32 mg/L.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted on read-across material

Justification for type of information:

Read-across to structurally similar substance DMTE (Dimethyltin bis (2-ethylhexyl thioglycolate) CAS 57583-35-4), see attached justification.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% CL 10 to 100 mg/L

Description of key information

Read-across to structurally similar substance DMTE (Dimethyltin bis (2-ethylhexyl thioglycolate) CAS 57583 -35 -4)

The 48 hour median effective concentration (EC50) of the WAF to daphnids was determined to be 32 mg/L. The 48 hour no observed effect concentration (NOEC) was determnined to be 10 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

32 mg/L

Additional information

Read-across to structurally similar substance DMTE (Dimethyltin bis (2-ethylhexyl thioglycolate) CAS 575 -35 -4)

The acute toxicity of the test material to the daphnid, Daphnia magna, was investigated in accordance with the standardised guideline OECD 202, under GLP conditions. The study was awarded a reliability score of 2 in accordance with the criteria set forth by Klimisch et al. (1997).

The test was performed under static conditions with the WAF of 0.10, 1.0, 10, 100 and 1000 mg/L mixtures of test material and water.

Under the conditions of the study, the 48 hour median effective concentration (EC50) of the WAF to daphnids wast determined to be 32 mg/L.