Triflumezopyrim

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

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 211 (Daphnia magna Reproduction Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1300 (Daphnid Chronic Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

UV-sterilized, filtered well water

Test organisms (species):

Daphnia magna

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

124 to 136 mg/L (as CaCO3)

Test temperature:

19.4 to 20.7°C

pH:

8.0 to 8.7

Dissolved oxygen:

≥7.3 mg/L (≥81% of saturation)

Conductivity:

326 to 401 μS/cm

Nominal and measured concentrations:

Nominal: 3.8, 7.5, 15, 30 and 60 mg a.s./L
Measured: 3.5, 7.0, 14, 28 and 57 mg a.s./L

Reference substance (positive control):

no

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

14 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Key result

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

28 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Key result

Duration:

21 d

Dose descriptor:

other: Maximum Acceptable Toxicant Concentration

Effect conc.:

20 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

57 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Immobility

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

> 57 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

28 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Growth and survival

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

57 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Survival

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

> 28 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth

Duration:

21 d

Dose descriptor:

other: MATC

Effect conc.:

40 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Survival

Validity criteria fulfilled:

yes

Conclusions:

21-Day NOEC (Daphnia Magna): 14 mg a.s./L (Reproduction)
21-Day LOEC (Daphnia Magna): 28 mg a.s./L (Reproduction)
MATC (Daphnia Magna): 20 mg a.s./L (Reproduction)
21-Day EC50 (Daphnia Magna): 57 mg a.s./L (Immobility)
21-Day EC50 (Daphnia Magna): >57 mg a.s./L (Reproduction)

Executive summary:

The Study was conducted according to guidelines, OECD Guideline 211 and US EPA, OPPTS Guideline 850.1300 to evaluate the effects of test substance on the survival, growth and reproduction of Daphnia magna in an unaerated, semi-static, 21-day test.

Treatments consisted of a dilution water control and five nominal test substance concentrations of 3.8, 7.5, 15, 30 and 60 mg a.s./L. The corresponding mean, measured concentrations were 3.5, 7.0, 14, 28 and 57 mg a.s./L, respectively.

A statistically significant reduction in percent survival was noted at the 57 mg a.s./L treatment group in comparison to the negative control. Consequently, the growth and reproduction data of the 57 mg a.s./L treatment concentration were excluded from the statistical analyses of growth and reproduction endpoints. A statistically significant reduction in reproduction, based on mean number of neonates produced per surviving adult, was found at the 28 mg a.s./L treatment concentration when compared to the negative control. Statistically significant differences were noted in mean dry weight at the 7.0 mg a.s./L treatment concentration, and in mean total length at the 3.5 and 28 mg a.s./L treatment concentrations when compared to the negative control. Since the mean dry weight at the 7.0 mg a.s./L treatment level did not follow a dose-response pattern, it was not considered to be biologically meaningful. Since the statistically significant reductions noted in mean total length at the 3.5 and 28 mg a.s./L treatment levels in comparison to the control were slight (4.1%), the statistically significant differences found were not considered to be biologically meaningful.

Therefore, the most sensitive endpoint of the study was reproduction. The 21-day NOEC and LOEC values for the study were 14 and 28 mg a.s./L, respectively. The MATC value was calculated to be 20 mg a.s./L. The 21-day EC₅₀ value for adult immobility was 57 mg a.s./L. The 21-day EC₅₀ value for reproduction was greater than 57 mg a.s./L.

Description of key information

21-day NOEC (Daphnia magna) = 14 mg/L; OECD 211; Reliability = 1

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

14 mg/L

Additional information

The NOEC from the 21-d chronic aquatic invertebrate toxicity test in Daphnia magna is 14 mg a.s./L, based on reproduction and development parameters.