Sodium diisobutyldithiophosphinate

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:

22-Feb-93 to 26-Feb-93

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Also complies with OECD GLP regulations. Deviations were limited, listed below, and are believed not to impact the reliability of the test result.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1984

Deviations:

yes

Remarks:

(see below)

Principles of method if other than guideline:

The dissolved oxygen levels dropped ( -40% of saturation) below the acceptable limit of 60% on Day 1 of study. It is not believed that initial low D.O.
values affected the study outcome. D.O. remained >60% in replicates that exhibited mortality.

GLP compliance:

yes

Remarks:

1 - It is unknown if the analysis to support the characterization of the test material was performed in a GLP compliant manner. 2 - It cannot be confirmed that the percent carbon analysis was performed in a GLP compliant manner.

Specific details on test material used for the study:

- Name of test material (as cited in study report): MRD-92-436; CT-519-92-C
- IUPAC nomenclature - Sodium diisobutyldithiophosphinate
- Appearance - Liquid
- CAS No. 13360-78-6
- Molecular Formula - C8H18PS2.Na
- Molecular Weight - 232 g/mole
- Purity 50% aqueous solution
- Storage condition of test material: At room temperature in the dark

Analytical monitoring:

yes

Details on sampling:

Samples were removed from each treatment on Day 0 and 4 (or at termination of replicate) and analyzed for carbon content.

Vehicle:

no

Details on test solutions:

A stock solution was prepared by adding the appropriate amount of test material to laboratory dilution water in an 8.0L glass aspirator bottle. The stock solution was mixed (<10% vortex) on a magnetic stirplate with a teflon coated stirbar for 1 hour. The stock solution appeared clear. Treatments were prepared by drawing the stock solution through the outlet at the bottom of the vessel and adding the appropriate amount to dilution water. Treatment solutions were then divided into 2 replicate chambers. Test chambers were covered with plexiglass to minimize evaporation and/or volatilization.

Test organisms (species):

Lepomis macrochirus

Details on test organisms:

TEST ORGANISM
- Common name: Bluegill sunfish
- Source: Aquatic Research Organisms, Hampton, NH 03842, USA

ACCLIMATION
- Acclimation period: 12 days
- Acclimation conditions: test conditions
- Type and amount of food during acclimation: Rangen Salmon Starter, Tetramin and/or 24 to 48-hour old brine shrimp nauplii
- Health during acclimation (any mortality observed): Mortality was insignificant.

FEEDING DURING TEST
None (taken off freed at least 24h before study start)

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

Observations for mortality, abnormal behavior and appearance of the fish were performed on all replicate chambers at 3.5, 24, 48, 72 and 96 hours (+/- 1 hr). Fish are considered dead if touching of the caudal peduncle produces no reaction. Water quality measurements (pH, dissolved oxygen and temperature) were performed daily on each chamber. No test material insolubility or feces were noted in any of the replicate chambers throughout the test period. Test chambers were aerated on Day 1 because the dissolved oxygen levels had dropped below the acceptable lilmit. Aeration was continued for the duration of the test.

After the 96-hour period, monitoring of environmental conditions was discontinued. Fish were euthanized using a benzocaine solution. Control fish were individually weighed and measured.

Hardness:

76 - 84 mg/L (Hardness as CaCO3 reported for water/carrier)

Test temperature:

21.9 °C

pH:

-Day 0: 7.4 - 7.6
-Day 1: 6.2 -6.5
-Day 2: 7.6 - 7.9
-Day 3: 7.5 - 7.8
-Day 4: 7.5 - 7.9

Dissolved oxygen:

-Day 0: 8.0 - 8.3 mg/L
-Day 1: 3.5 - 6.5 mg/L
-Day 2: 8.4 - 8.5 mg/L
-Day 3: 8.3 - 8.4 mg/L
-Day 4: 8.0 - 8.1 mg/L

Nominal and measured concentrations:

Nominal treatment levels for the test were 1000mg/L, 500mg/L, 250mg/L, 125mg/L, 62.5mg/L and a control.

Details on test conditions:

TEST SYSTEM
- Material, size, headspace, fill volume: 2.0L glass culture dish
- Aeration: Yes
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- Biomass loading rate: 0.725 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ground water from a well located at the testing facility
- Metals: None dected or Below the minimum detection limits
- Pesticides: None detected
- Chlorine: < 0.1 mg/L
- Alkalinity: 27-29 mg/L

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16h light / 8h dark
- Light intensity: Daylight intensity ranged from 62.54 to 63.69 footcandles during full daylight periods of the study

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2

Range finding study :
- Test concentrations: Nominal concentrations were 3, 10, 70, 300 and 1000 mg/L and a control; 1 chamber/concentration, 5 fish/chamber.

Reference substance (positive control):

no

Duration:

3.5 h

Dose descriptor:

LC50

Effect conc.:

750 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 500-1000mg/L

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

375 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 250-500 mg/L

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

375 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 250-500mg/L

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

375 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 250-500mg/L

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

375 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 250-500mg/L

Details on results:

The minimum concentration causing 100% mortality was 500mg/L. The maximum concentration causing no mortality was 250mg/L. One mortality occurred in the control that was not test related and was excluded from the statistical analysis.

Validity criteria fulfilled:

not specified

Conclusions:

A bluegill sunfish (Lepomis macrochirus) acute test was performed to evaluate the toxicity of the test material.
The 96-hour LC50 was 375mg/L with 99% confidence intervals of 250 to 500mg/L.

Executive summary:

A bluegill sunfish (Lepomis macrochirus) acute test was performed to evaluate the toxicity of the test material according to OECD 203 and under GLP conditions.

Preliminary methods development indicated that mixing the test material in dilution water for ~1 hour was most appropriate for this study. The nominal treatment levels for the test were 1000mg/L, 500mg/L, 250mg/L, 125mg/L, 62.5mg/L and a laboratory dilution water control. A stock solution was prepared by adding the appropriate amount of test material to laboratory dilution water in an 8.0L glass aspirator bottle. The stock solution was mixed (<10% vortex) on a magnetic stirplate with a teflon coated stirbar for 1 hour. The stock solution appeared clear. Treatments were prepared by drawing the stock solution through the outlet at the bottom of the vessel and adding the appropriate amount to dilution water. Samples were removed from each treatment and analyzed for carbon content. The bluegills were exposed to each treatment level for a 96-hour period.

The calculated material values were >80% of the nominal concentrations.

The 96 -hour LC50 was 375mg/L with 99% confidence intervals of 250 to 500mg/L.

Description of key information

A bluegill sunfish (Lepomis macrochirus) acute test was performed to evaluate the toxicity of the test material, resulting in a 96 h LC50 of 375 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

375 mg/L

Additional information

A bluegill sunfish (Lepomis macrochirus) acute test was performed to evaluate the toxicity of the test material according to OECD 203 and under GLP conditions. Preliminary methods development indicated that mixing the test material in dilution water for ~1 hour was most appropriate for this study. The nominal treatment levels for the test were 1000mg/L, 500mg/L, 250mg/L, 125mg/L, 62.5mg/L and a laboratory dilution water control. A stock solution was prepared by adding the appropriate amount of test material to laboratory dilution water in an 8.0L glass aspirator bottle. The stock solution was mixed (<10% votex) on a magnetic stirplate with a teflon coated stirbar for 1 hour. The stock solution appeared clear. Treatments were prepared by drawing the stock solution through the outlet at the bottom of the vessel and adding the appropriate amount to dilution water. Samples were removed from each treatment and analyzed for carbon content. The bluegills were exposed to each treatment level for a 96-hour period.

The calculated material values were >80% of the nominal concentrations.

The 96 -hour LC50 was 375mg/L with 99% confidence intervals of 250 to 500mg/L.