8-Chloro-6-(trifluoromethyl)imidazo[1,2-a]pyridine-2-carboxylic acid

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OCSPP 850.4500 (Algal Toxicity) (January 2012)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

1

Reference substance name:

8-chloro-6-(trifluoromethyl)imidazo[1,2-a]pyridine-2-carboxylic acid

Cas Number:

353258-35-2

Molecular formula:

C9H4ClF3N2O2

IUPAC Name:

8-chloro-6-(trifluoromethyl)imidazo[1,2-a]pyridine-2-carboxylic acid

Specific details on test material used for the study:

Test substance: IN-QEK31-011
Batch No.: SG0312574
Purity: 98.2%

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

yes

Remarks:

OECD test media

Test organisms

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Study design

Test type:

static

Water media type:

other: OECD test media

Total exposure duration:

96 h

Test conditions

Test temperature:

23.3 - 24.4°C

pH:

6.8 to 8.1 at test initiation and 9.0 to 9.3 at test termination

Nominal and measured concentrations:

Nominal Concentration: 0, 7.5, 15, 30, 60, 120, and 120 (abiotic control) mg a.s./L
Measured Concentration (72 h): 0, 7.51, 15.1, 30.0, 60.2, and 116, and 116 (abiotic control) mg a.s./L
Measured Concentration (96 h): 0, 7.37, 14.9, 29.9, 59.4, and 116, and 116 (abiotic control) mg a.s./L

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 116 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

other: area under the growth curve, yield, and growth rate from time zero

Remarks:

Area Under Growth Curve

Effect concentrations 2

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 116 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

other: area under the growth curve, yield, and growth rate from time zero

Effect concentrations 3

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

116 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

other: area under the growth curve, and growth rate from time zero

Effect concentrations 4

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

7.51 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

yield

Effect concentrations 5

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

116 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

other: area under the growth curve, yield, and growth rate from time zero

Effect concentrations 6

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

> 116 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

other: area under the growth curve, and growth rate from time zero

Effect concentrations 7

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

15.1 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

yield

Effect concentrations 8

Duration:

96 h

Dose descriptor:

LOEC

Effect conc.:

> 116 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

other: area under the growth curve, yield, and growth rate from time zero

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

72-hour EC50: > 116 mg a.s./L (area under the growth curve, yield, and growth rate from time zero)
96-hour EC50: > 116 mg a.s./L (area under the growth curve, yield, and growth rate from time zero)
72-hour NOEC: 116 mg a.s./L (area under the growth curve, and growth rate from time zero)
72-hour NOEC: 7.51 mg a.s./L (yield)
96-hour NOEC: 116 mg a.s./L (area under the growth curve, yield, and growth rate from time zero)
72-hour NOEC: >116 mg a.s./L (area under the growth curve, and growth rate from time zero)
72-hour NOEC: 15.1 mg a.s./L (yield)
96-hour NOEC: >116 mg a.s./L (area under the growth curve, yield, and growth rate from time zero)

Executive summary:

The acute toxicity of the test item to the unicellular green alga, Pseudokirchneriella subcapitata, was determined in a 96-hour growth inhibition test. The test was conducted in accordance with the U.S. Environmental Protection Agency, Ecological Effects Test Guidelines, OCSPP 850.4500 and OECD Guideline No. 201. Treatments consisted of an untreated control, an abiotic (stability) control, and five nominal concentrations of 7.5, 15, 30, 60, and 120 mg a.s./L. The corresponding 72-hour mean measured concentrations of the test item were 7.51, 15.1, 30.0, 60.2, and 116 mg a.s./L. The corresponding 96-hour mean measured concentrations of the test item were 7.37, 14.9, 29.9, 59.4, and 116 mg a.s./L. The 96-hour measured concentration of the test item in the nominal 120 mg a.s./L abiotic control was 116 mg a.s./L. The 72- and 96-hour EC50 and NOEC for Pseudokirchneriella subcapitata were based on 72- and 96-hour mean, measured concentrations, respectively, of the test item and area under the growth curve, growth rate, and yield. The 72-hour EbC50, ErC50, and EyC50 values based on area, growth rate, and yield were >116 mg a.s./L. The 72-hour NOEC value based on area, growth rate, and yield was 116, 116, and 7.51 mg a.s./L (72-hour mean, measured concentrations), respectively. The 96-hour EbC50, ErC50, and EyC50 values based on area, growth rate, and yield were >116 mg a.s./L. The 96-hour NOEC value based on area, growth rate, and yield were 116 mg a.s./L (96-hour mean measured concentrations), respectively.