2-ethylhexyl 10-ethyl-4,4-dimethyl-7-oxo-8-oxa-3,5-dithia-4-stannatetradecanoate

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Preferred study for this SIDS endpoint; GLP guideline study. No analytical confirmation of exposure concentrations.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity 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 at the beginning of the test. The WAF was formulated by combining 25.0 g of test substance and 25 liters of dilution water in a glass mixing vessel equipped with a magnetic stirrer ( the vortex extended approximately 10% of the distance from the surface to the bottom of the mixing vessel). The mixture was stirred for approximately 24 hours and allowed to settle for approximately 1 hour. Following the settling period the water phase containing the WAF was removed for 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 WAF and dilution water. The dilution water hardness was 40-180 mg/L.
- Eluate: No data
- Differential loading: 0.16 g/L
- Controls: 0 (Control)
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): None
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): 0, 1.10, 1.0, 10, 100, and 1,000 mg/L
- Evidence of undissolved material (e.g. precipitate, surface film, etc): No insoluble material was noted in the test vessels containing the WAF of Alkyltin MA.

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: Fathead Minnow
- Strain: Pimephales promelas
- Source: Aquatic Biosystems, Inc., Fort Collins, Colorado on August 10, 1995
- Age at study initiation (mean and range, SD): juvenile
- Length at study initiation (length definition, mean, range and SD): average total length 31.5 mm
- Weight at study initiation (mean and range, SD): average wet weight 0.25 g
- Method of breeding:
- Feeding during test not fed during the test


ACCLIMATION
- Acclimation period: 14 day
- Acclimation conditions (same as test or not): flow through conditions; not under test conditions
- Type and amount of food: dry commercial food - Tetra Min Staple Food
- Feeding frequency: daily except during the 48 hours immediately preceeding the test
- Health during acclimation (any mortality observed): not treated for disease and free from apparent sickness, injuries and abnormalities; mortality <3%

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

no data

Hardness:

40 mg/l as CaCO3

Test temperature:

22.1-22.6 deg. C

pH:

7.2-7.8

Dissolved oxygen:

6.0-8.9 mg/l

Salinity:

no data

Nominal and measured concentrations:

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

Details on test conditions:

TEST SYSTEM
- Emybro cups (if used, type/material, size, fill volume): No data
- Test vessel: 20 L
- Type (delete if not applicable): open / closed - Test vessels were loosely covered
- Material, size, headspace, fill volume: 20 liter glass aquaria
- Aeration: None, Aeration was not needed to maintain dissolved oxygen concentrations above acceptable levels.
- Type of flow-through (e.g. peristaltic or proportional diluter): Static
- Renewal rate of test solution (frequency/flow rate): None
- No. of fertilized eggs/embryos per vessel: 10
- No. of vessels per concentration (replicates): Single
- No. of vessels per control (replicates): Single
- No. of vessels per vehicle control (replicates): Single
- Biomass loading rate: 0.16 g/L


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Water used for acclimation of test organisms and for all toxicity testing was deionized tap water. Water was adjusted to a hardness of 40-48 mg/L and an alkalinity of 29 mg/L as CaCO3 at the start of the toxicity test and stored in 500-gallon polyethylene tanks where it was aerated and continuously passed through a particle filter, ultraviolet sterilizer, and activated carbon.

- Total organic carbon: non detect
- Particulate matter: No data
- Metals: non detect
- Pesticides: non detect
- Chlorine: non detect
- Alkalinity: 29 mg/l CaCO3
- Ca/mg ratio: No data
- Conductivity: 130-150 umhos/cm
- Salinity: No data


OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod: 16 hour light and 8 hour dark
- Light intensity: cool-white fluorescent lights provided a light intensity of approximately 3 µEin/m2sec. A 15 minute transition period was provided between light and dark.


EFFECT PARAMETERS MEASURED (with observation intervals if applicable): The number of surviving organisms and the presence of sub lethal effects was determined visually and recorded initially and after 24, 48, 72, and 96 hours.


VEHICLE CONTROL PERFORMED: No

RANGE-FINDING STUDY
- Test concentrations: 0.10, 1.0, 10, 100, and 1,000 mg/L
- Results used to determine the conditions for the definitive study: One hundred percent survival occurred in the control and no control sub lethal effects were noted during the test. Survival at all tested concentrations was at least 90% after 96 hours. All of the surviving fish exposed to the 1,000 mg/L WAF were lethargic at 48, 72, and 96 hours (also exhibiting a loss of equilibrium at 72 hours). No other sub lethal effects were noted during the toxicity test. The 96 hour LC50 of the WAF of Alkyltin MA (expressed as the nominal amount of test substance used to prepare the WAF) is greater than 1,000 mg/L and the 96 hour NOEC is 100 mg/L.





POST-HATCH DETAILS
- Begin of post-hatch period: No data
- No. of hatched eggs (alevins)/treatment released to the test chamber: No data
- Release of alevins from incubation cups to test chamber on day no.: No data


FERTILIZATION SUCCESS STUDY
- Number of eggs used: NA
- Removal of eggs to check the embryonic development on day no.: NA

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks:

:lethargic

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Mortality/survival at embryo, larval, juvenile, and adult stages:
One hundred percent survival occurred in the control and no control sublethal effects were noted during the test. Survival at all tested concentrations was at least 90% after 96 hours. All of the surviving fish exposed to the 1,000 mg/L WAF were lethargic at 48, 72, and 96 hours (also exhibiting a loss of equilibrium at 72 hours). No other sublethal effects were noted during the toxicity test. The 96 hour LC50 of the WAF of Alkyltin MA (expressed as the nominal amount of test substance used to prepare the WAF) is greater that 1,000 mg/L and the 96 hour NOEC is 100 mg/L
- Days to hatch or time to release of young: No data
- Numbers hatched, Numbers of offspring produced, or Number of offspring per live female per day: No data
- Number of fish in swim-up stage at one or more time periods (e.g., day x1, x2): No data
- Observations on body length and weight of young and/or exposed parents at one or more time periods: At the conclusion of the test the control fish had and average total length of 31.5 mm and an average wet weight of 0.25 g (loading rate was approximately 0.16 g/L)
- Number of healthy fish at end of test: 100% survival occurred in the control and no control sub lethal effects were noted during the test. Survival at all test concentrations was at least 90% after 96 hours.
- Type of and number with morphological abnormalities: NA
- Type of and number with behavioral abnormalities: All of the surviving fish exposed to the 1,000 mg/L WAF were lethargic at 48, 72, and 96 hours (also exhibiting a loss of equilibrium at 72 hours). No other sub lethal effects were noted during the toxicity test.
- Type and number of developmental effects: NA
- Type and magnitude of hormonal changes: NA
- Other biological observations: None
- Effect concentrations exceeding solubility of substance in test medium: greater than 1,000 mg/L
- Incidents in the course of the test which might have influenced the results: None of the test organisms survived exposure to all tested concentrations of the test substance.

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

No statistical analyses were performed because >50% of the test organisms survived exposure to all concentrations tested. The NOEC was defined as the highest concentration tested that allows at least 90% survival and does not cause sublethal effects.

Sublethal observations / clinical signs:

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: 100% survival
1000 mg/l: 90% survival

Validity criteria fulfilled:

yes

Conclusions:

Exposure of fathead minnows (Pimephales promelas) to the test substance resulted in a 96-h LC50 of >1000 mg/L and a NOEC of 100 mg/L based on survival and sublethal effects.

Executive summary:

The acute toxicity of the WAF of the test substance to the fathead minnow, Pimephales promelas, was investigated during a range-finding study. The test was performed under static conditions with the WAF of 0.10, 1.0, 10, 100 and 1000 mg/L mixtures of test substance and water.

Survival at all tested concentrations was at least 90% after 96 hours. All of the surviving fish exposed to the 1000 mg/L WAF were lethargic at 48, 72 and 96 hours (also exhibiting a loss of equilibrium at 72 hours). No other sublethal effects were noted during the toxicity test. The 96 hour median lethal concentration (LC50) of the WAF of the test substance to fathead minnows is >1000 mg/L. The 96 hour no observed effect concentration (NOEC) is 100 mg/L.

Description of key information

LC50 (96h) >1000 mg/L WAF for fathead minnows (Pimephales promelas) (OECD 203)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

1 000 mg/L

Additional information

The acute toxicity testing available for the test substance is a range-finding study conducted with fathead minnow (Pimephales promelas). The study was performed under GLP conditions and followed OECD testing guideline 203. A water accommodated fraction (WAF) of the test substance was prepared for testing. The NOEC was defined as the highest concentration tested that allows at least 90% survival and does not cause sublethal effects. The 96 -hr NOEC was 100 mg/L based on sublethal effects, i.e. lethargy. The 96 -hr LC50 was >1000 mg/L.