Triflumezopyrim

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:

EPA OPPTS 850.1075 (Freshwater and Saltwater Fish Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 6.9, 14, 28, 55 and 110 mg a.s./L
- Sample storage conditions before analysis: stored refrigerated
- Duplicate 20 mL samples were collected from each test chamber at the beginning of the test and at 96 hours (± 1 hour) to measure the concentration of test substance in the treatment solutions. Two sets of samples were collected at each interval. All samples were collected at mid-depth from the test chambers and placed in glass scintillation vials. One set was processed immediately for analysis. The second set was stored refrigerated for possible future analysis. Due to the presence of precipitate in the 55 and 110 mg a.s./L test solutions, all solutions were centrifuged prior to analysis.

Vehicle:

yes

Remarks:

Dilution water

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
Individual test solutions were prepared directly in each test chamber. Solutions were prepared at nominal concentrations of 6.9, 14, 28, 55 and 110 mg a.s./L by mixing calculated amounts of test substance in volumetric flasks with a portion of the dilution water. The flask contents were sonicated for 76 minutes and were then poured into the appropriate test chambers. The solutions were mixed with electric top-down mixers for approximately 24 hours.
- Test substance eluted as a well-resolved peak with a retention time of approximately 7.1 minutes

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow Trout
- Strain: Oncorhynchus mykiss
- Source: Thomas Fish Company, Anderson, California
- Age at study initiation: Juveniles
- Length at end of the test: 5.5 – 6.1 cm
- Weight at end of the test: 1.39 – 1.79 g

ACCLIMATION
- Acclimation period: At least 14 days
- Acclimation conditions: same as test
- Type and amount of food during acclimation: Commercially prepared diet
- Feeding frequency during acclimation: Daily
- Health during acclimation (any mortality observed): No moratilty and the fish showed no signs of disease or stress.

FEEDING DURING TEST
- The fish were unfed during test

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Post exposure observation period:

Approximately 2.5 hours and every 24 hours following initiation of exposure (±1 hour).

Hardness:

128 mg/L as CaCO3

Test temperature:

11.3 – 12.2°C in test chambers; 11.7 – 12.5°C measured continuously in the negative control.

pH:

8.1 – 8.5

Dissolved oxygen:

≥7.5 mg/L (≥69% of saturation)

Conductivity:

specific conductance: 393 μS/cm

Nominal and measured concentrations:

Nominal: 6.9, 14, 28, 55 and 110 mg a.s./L.
Measured: 6.6, 13, 27, 54 and 107 mg a.s./L.

Details on test conditions:

TEST SYSTEM
- Test vessel: 54-L stainless steel aquaria holding 30 L of test solution (17.0 cm liquid depth)
- Aeration: Unaerated
- Type of flow-through: Static
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): A single replicate test chamber was maintained in each treatment and control group.
- Biomass loading rate: 0.36 g fish/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Freshwater obtained from a well approximately 40 meters deep located at test facility.
- Alkalinity: 178 mg/L as CaCO3
- Culture medium different from test medium: No

OTHER TEST CONDITIONS
- Adjustment of pH: 8.1 – 8.5
- Photoperiod: 16 hr light and 8 hr dark including 30 min transitional period preceding and following the 16-hr light interval.
- Light intensity: 376 lux

EFFECT PARAMETERS MEASURED
- Observations were made periodically to determine the numbers of dead organisms in each treatment group. Lethality was defined as a lack of visible movement by the test organism. The numbers of individuals exhibiting signs of toxicity or abnormal behavior also were evaluated. Observations were made approximately 2.5, 24, 48, 72, and 96 hours after test initiation.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 107 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: Highest concentration tested

Reported statistics and error estimates:

The absence of mortality in any of the test substance treatment groups during the test precluded the statistical calculation of LC50 values at 24, 48, 72 and 96 hours. Therefore, the LC50 values were estimated to be greater than the highest concentration tested. The highest mean measured test concentration causing no immobility at test end and the lowest mean measured test concentration causing 100% immobility at test end were assessed by visual observation of the immobility and observation data.

Validity criteria fulfilled:

yes

Conclusions:

96 Hr LC50 (Rainbow Trout): >107 mg a.s./L (mortality) (Highest concentration tested)

Executive summary:

The test was conducted in accordance with the OECD Guideline 203, Fish Acute Toxicity Test and U.S.EPA OPPTS 850.1075 to determine acute toxicity of test substance to unfed juvenile rainbow trout, Oncorhynchus mykiss, a cold freshwater fish, in an unaerated, static, 96-hour dose response test.

Treatments consisted of a dilution water control and five nominal test substance concentrations of 6.9, 14, 28, 55 and 110 mg a.s./L. The mean, measured concentrations were 6.6, 13, 27, 54 and 107 mg a.s./L, representing 96, 93, 96, 98, and 97% of nominal test substance concentrations, respectively. A single replicate test chamber was maintained in each treatment and control group, with seven fish each (total of seven fish in the dilution water control and in each test concentration). Mortality and behavioral observations were made at approximately 2.5 hours and every 24 hours following initiation of exposure (±1 hour). and no mortality was observed in any of the test substance treatment groups during the test.

The 96-hour LC₅₀ for rainbow trout, based on mean measured concentrations of test substance and mortality, was estimated to be >107 mg a.s./L. The highest mean measured test concentration causing no mortality was 107 mg a.s./L. The lowest mean measured test concentration causing 100% mortality was >107 mg a.s./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:

other: Guidelines for Preparation of Study Results Submitted when Applying for Registration of Agricultural Chemicals"; Aquatic Organism Effect Study; Fish Acute Toxicity Studies (2-7-1-1)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

Dechlorinated tap water

Test organisms (species):

Cyprinus carpio

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

3, 24, 48, 72 and 96 hours

Hardness:

30 mg/L (as CaCO3)

Test temperature:

23 ±1°C

pH:

7.8 to 7.9

Dissolved oxygen:

7.8 to 8.4 mg/L

Conductivity:

13 mS/m

Nominal and measured concentrations:

Nominal: 100 mg a.i./L
Measured (mean value): 95 to 96 mg a.i./L

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

LC50 (Common carp): >100 mg a.i./L (mortality)

Executive summary:

The study was conducted according to guideline OECD Guideline 203 to determine 96-hour acute toxicity study of test substance in Common carp. The study was conducted as a limit test at a nominal concentration of 100 mg a.i./L with one replicate for one test level and seven fish in each test level .Observations of mortality and visible abnormality were conducted at 3, 24, 48, 72 and 96 hours after the start of exposure.

The results showed that no mortality and no abnormal responses was observed in the fish due to exposure of test substance. Based on no mortality, the 96-hour LC₅₀ of the test item for Common carp is >100 mg a.i./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:

EPA OPPTS 850.1075 (Freshwater and Saltwater Fish Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Cyprinodon variegatus

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

2, 24, 48, 72, and 96 hours

Test temperature:

22.1 to 22.3°C

pH:

7.9 to 8.2

Dissolved oxygen:

≥6.1 mg/L (≥78% of saturation)

Salinity:

20%

Nominal and measured concentrations:

Nominal: 7.5, 15, 30, 60 and 120 mg a.s./L.
Mean Measured: 7.9, 15, 30, 63 and 116 mg a.s./L

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 116 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

116 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

> 116 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

96Hr LC50 (Sheepshead minnow): >116 mg a.s./L (mortality) (Highest concentration tested)

Executive summary:

The Study was conducted according to guidelines, OECD Guideline 203 and US EPA OPPTS 850.1075 to determine the 96 -Hour static acute toxicity of test substance in the Sheepshead minnow (Cyprinodon variegatus).

Treatments consisted of a dilution water control and five nominal test substance concentrations of 7.5, 15, 30, 60 and 120 mg a.s./L. The mean, measured concentrations were 7.9, 15, 30, 63 and 116 mg a.s./L, representing 105, 100, 100, 105 and 97% of nominal test substance concentrations, respectively. Mortality and behavioral observations were made at approximately 2 hours and every 24 hours following initiation of exposure (± 1 hour).

The results showed that the 96-hour LC₅₀ of test substance in Sheepshead minnow was greater than 116 mg a.s./L, based on mean measured concentrations of test substance and mortality. The highest mean measured test concentration causing no mortality was 116 mg a.s./L. The lowest mean measured test concentration causing 100% mortality was >116 mg a.s./L.

Description of key information

96 -hour LC50 (Oncorhynchus mykiss, Rainbow trout): > 107 mg/L; OECD 203; Reliability =1

96 -hour LC50 (Cyprinus carpio, common carp): > 100 mg/L; OECD 203; Reliability =1

96 -hour LC50 (Cyprinodon variegatus, Sheepshead minnow): > 116 mg/L; OECD 203; Reliability =1

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

107 mg/L

Marine water fish

Marine water fish

Effect concentration:

116 mg/L

Additional information

Acute fish toxicity tests were conducted in three freshwater species. Acute 96 -hour LC50 values in freshwater species were all > 100 mg/L. The marine fish species tested, Cyprinodon variegatus showed similar toxicity to freshwater species, with the mean measured acute LC50 > 116 mg/L.