Methyl (R)-2-(4-(3-chloro-5-trifluoromethyl-2-pyridyloxy)phenoxy)propionate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: U.S. EPA - FIFRA Standard Evaluation Procedure 540/9-85-006

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPP 72-1 (Fish Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Haloxyfop-R methyl ester
Substance ID: NB10150401, TSN101748
Purity: 98.4%

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 93.3, 156, 259, 432, 720, and 1200 µg/L of dilution water
- Sampling method: Test solutions were sampled from each of the individual aquaria on days 0 and 4

Vehicle:

yes

Remarks:

acetone and laboratory dilution water

Details on test solutions:

Aquaria were replenished on a regular intermittent cycle with test solutions delivered from a flow-through proportional diluter fortified from a primary feedstock prepared at a nominal concentration of 13.7 mg test substance/mL acetone. During each cycle of the diluter, 0.5 mL of this stock was injected into ~5.7 L of laboratory dilution water. This resulted in nominal concentrations of 1200, 720, 432, 259, 156, and 93.3 µg test substance/L being delivered with each cycle of the diluter. The initial stock solution was adjusted based on 98.4% purity of the test substance.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Strain: Oncorhynchus
- Source: Mt. Lassen Trout Farm, Red Bluff, California
- Length at study initiation: 2.2 cm
- Weight at study initiation: 0.219 g

ACCLIMATION
- Acclimation period: At least 14 days
- Type and amount of food during acclimation: Standard diet (Aquatic Diet Number 1 Lot #992236, Harlan-Teklad, Madison, Wisconsin)
- Feeding frequency during acclimation: At least once daily
- Health during acclimation (any mortality observed): Mortality did not exceed 5% of the population in the 48 hours before testing

FEEDING DURING TEST
- Food type: Fish were not fed during the test

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

58-60 mg/L CaCO3

Test temperature:

12.0-12.9°C (12.5 ± 0.2°C)

pH:

6.8-7.4 (7.1 ± 0.1)

Dissolved oxygen:

8.5-9.8 mg/L (9.4 ± 0.3 mg/L) (average of 82% of saturation-based on a theoretical value of 10.4 mg/L)

Conductivity:

129-134 µmho/cm

Nominal and measured concentrations:

Nominal: 93.3, 156, 259, 432, 720, and 1200 µg/L
Measured: 68.9, 128, 227, 388, 679 and 1203 µg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: double-strength glass held together with clear silicone adhesive
- Type (delete if not applicable): Closed
- Material, size, headspace, fill volume: Glass; 30 x 15.5 x 12.5 cm
- Aeration: Aeration was not required to maintain the required dissolved oxygen levels
- Type of flow-through: Proportional diluter
- Renewal rate of test solution: Regular intermittent cycle
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- No. of vessels per vehicle control (replicates): 2
- Biological loading rate: 0.488 g fish/L (standard loading rate: 0.0346 g/L/day)

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Upper Saginaw Bay of Lake Huron off Whitestone Point

OTHER TEST CONDITIONS
- Adjustment of pH: pH was recorded in each test vessel at 0, 24, 48, 72 and 96 hours
- Photoperiod: 16-h light/8-h dark transitional photoperiod

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : The fish were observed after 6 hours of exposure and every 24 hours thereafter for mortality (no response to touching of the caudal peduncle and no opercular movement) and sublethal effects.

TEST CONCENTRATIONS
Range finding study
- Test concentrations: 0 (laboratory water control and 0.09 mL/L acetone solvent control) and 1200, 720, 432, 259, 156, and 93.3 µg/L
- Results used to determine the conditions for the definitive study: The biological results from the probe study indicated the LC50 value to fall between 432 and 720 µg/L dose levels (nominal).

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

460 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 400-528 µg/L

Key result

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

460 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 400-528 µg/L

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

485 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 392-604 µg/L

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

854 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 767-951 µg/L

Duration:

6 h

Dose descriptor:

LC50

Effect conc.:

> 1 203 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Highest dose tested

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

227 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

227 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

227 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

227 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

6 h

Dose descriptor:

NOEC

Effect conc.:

227 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

Complete loss of equilibrium was observed in 60% (6/10) of the fish at the 1203 µg/L dose level after 6 hours of exposure and mortality was observed in30% (3/10) and 100% (10/10) of the fish after 6 and 24 hours of exposure, respectively. No sublethal effects or mortality were observed in the 679 µg/L dose level after 6 hours of exposure. Complete loss of equilibrium and ascites were observed in 50% (5/10) and complete loss of equilibrium in 10% of the fish in the 679 µg/L dose level after 24 and 48 hours of exposure, respectively. Mortality was observed in 10% (1/10) and 100% (10/10) of the fish in the 679 µg/L dose level following 48 and 72 hours of exposure, respectively. Lethargy was observed in 10% (1/10) of the fish after 6 and 24 hours of exposure and partial loss of equilibrium observed in 10% (1/10) of the fish after 48 hours of exposure in the 388 µg/L dose level. Mortality was observed in 20% (2/10) of the fish in the 388 µg/L dose level after 48 hours of exposure with no further mortalities or sublethal effects observed after 72 and 96 hours of exposure. No sublethal effects or mortalities were observed in the 227, 128, and 68.9 µg/L dose levels or in the water and solvent controls.

Validity criteria fulfilled:

yes

Conclusions:

72 and 96 h LC50 (Rainbow Trout): 460 µg/L

Executive summary:

The test substance was tested for its acute toxicity to the rainbow trout, Oncorhynchus mykiss Walbaum, over a 96-hour test period. These data were used to determine the LC50 (the concentration that is lethal to 50% of the test population) and a no-observed-effect concentration (NOEC). The study was conducted following OECD guideline 203, EPA guideline 72-1.

Definitive testing was conducted with ten fish per dose level at mean measured concentrations of 0 (laboratory water and solvent controls), 68.9, 128, 227, 388, 679 and 1203 µg/L over the 4 day exposure period. Test solutions were prepared by a proportional diluter system with a primary stock solution concentration of 13.7 mg/mL acetone carrier solvent. Samples of test solutions were obtained from all test vessels on days 0 and 4, and subsequently analyzed by high-performance liquid chromatography with an ultraviolet absorbance detector (HPLC/UV) for the test substance.

The 6-hour LC50 value for the test substance with the rainbow trout was greater than the highest concentration tested of 1203 µg/L. The 24-hour LC50 value was 854 µg/L, with a 95% confidence interval of 767-951 µg/L. The 48-hour LC50 value was 485 µg/L, with a 95% confidence interval of 392-604 µg/L, The 72- and 96-hour LC50 value was 460 µg/L, with a 95% confidence interval of 400-528 µg/L.

The 6-, 24-, 48-, 72- and the 96-hour no-observable effect concentration (NOEC) for the test substance with the rainbow trout was 227 µg/L.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: U.S. EPA - FIFRA Standard Evaluation Procedure 540/9-85-006

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPP 72-1 (Fish Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Haloxyfop-R methyl ester
Substance ID: NB10150401, TSN101748
Purity: 98.4%

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

acetone and laboratory dilution water

Test organisms (species):

Lepomis macrochirus

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

52-58 mg/L CaCO3

Test temperature:

22.1-22.5°C (22.3 ± 0.1°C)

pH:

6.6-7.2 (6.9 ± 0.1)

Dissolved oxygen:

6.0-8.3 mg/L (7.3 ± 0.5 mg/L) (average of 86% of saturation-based on a theoretical value of 8.5 mg/L)

Conductivity:

129-134 µmho/cm

Nominal and measured concentrations:

Nominal: 35.0, 58.3, 97.2, 162, 270, and 450 µg/L
Measured: 37.6, 57.5, 113, 175, 292, and 487 µg/L

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

88.4 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 54.1-114 µg/L

Key result

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

106 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 81.4-131 µg/L

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

147 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 123-176 µg/L

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

264 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 227-306 µg/L

Duration:

6 h

Dose descriptor:

LC50

Effect conc.:

> 487 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Highest dose tested

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

37.6 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

37.6 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

37.6 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

37.6 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

6 h

Dose descriptor:

NOEC

Effect conc.:

37.6 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

96 h LC50 (Bluegill sunfish): 88.4 µg/L

Executive summary:

The test substance was tested for its acute toxicity to the bluegill sunfish, Lepomis macrohirus Rafinesque, over a 96-hour test period. These data were used to determine the LC50 (the concentration that is lethal to 50% of the test population) and a no-observed-effect concentration (NOEC). The study was conducted following OECD guideline 203, EPA guideline 72-1.

Definitive testing was conducted with ten fish per dose level at mean measured concentrations of 0 (laboratory water and solvent controls), 37.6, 57.5, 113, 175, 292 and 487 µg/L over the 4 day exposure period. Test solutions were prepared by a proportional diluter system with a primary stock solution concentration of 5.14 mg/mL acetone carrier solvent. Samples of test solutions were obtained from all test vessels on days 0 and 4, and subsequently analyzed by high-performance liquid chromatography with an ultraviolet absorbance detector (HPLC/UV) for the test substance.

The 6-hour LC50 value for the test substance with the bluegill sunfish was greater than the highest concentration tested of 487 µg/L. The 24-hour LC50 value was 264 µg/L, with a 95% confidence interval of 227-306 µg/L. The 48-hour LC50 value was 147 µg/L, with a 95% confidence interval of 123-176 µg/L, The 72-hour LC50 value was 106 µg/L, with a 95% confidence interval of 81.4-131 µg/L. The 96-hour LC50 value for test substance was 88.4 µg/L, with a 95% confidence interval of 54.1-114 µg/L.

The 6-, 24-, 48-, 72- and the 96-hour no-observable effect concentration (NOEC) for the test substance with the bluegill sunfish was 37.6 µg/L.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

XRD-535 Methyl
Lot #: RN 88-7R
Purity: 98%

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

Tween 80, i.e., polyoxyethylene sorbitan monooleate

Test organisms (species):

Leuciscus idus

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

18-19.5°C

pH:

7.7-8.1

Dissolved oxygen:

8.2-9.6 mg O2 per litre

Nominal and measured concentrations:

Nominal: 0.53, 0.95, 1.71, 3.09, 5.56, 10 mg/L

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.99 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

1.71 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

0.53 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

0.53 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LOEC

Effect conc.:

0.95 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

96 h LC50 (Golden orfe): 0.99 mg/L

Executive summary:

The test substance was tested for its acute toxicity to the Golden orfe. The tests were performed according to the OECO Guideline 203 and EEC C.1.

After 96 hours the LC0 and LC100 were determined to be 0.53 mg/L and 1.71 mg/L, respectively. The LC50 value was estimated to be (Logit-model) 0.99 mg/L. The NOEC and LOEC were found to be 0.53 mg/L and 0.95 mg/L, respectively.

Description of key information

96 -hour LC50 (Oncorhynchus mykiss, Rainbow trout): 460 µg/L; OECD 203, EPA 72-1, Reliability = 1

96 -hour LC50 (Lepomis macrohirus, Bluegill sunfish): 88.4 µg/L; OECD 203, EPA 72-1, Reliability = 1

96 -hour LC50 (Leuciscus idus, Golden orfe): 0.99 mg/L; OECD 203, EU Method C.1, Reliability = 1

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

88.4 µg/L

Additional information

The test substance was tested in 3 freshwater species. Acute 96 -hour LC50 values in freshwater species ranged from 88.4 μg/L to 990 μg/L.