2-nitro-4-(trifluoromethyl)benzonitrile

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 Feb – 22 Mar 2019

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

GLP compliance:

yes

Remarks:

The test was performed in compliance with the requirements of the Principles of Good Laboratory Practices (GB/T 22278-2008).

Test material

Test material information

Constituent 1

Reference substance name:

2-nitro-4-(trifluoromethyl)benzonitrile

EC Number:

212-298-1

EC Name:

2-nitro-4-(trifluoromethyl)benzonitrile

Cas Number:

778-94-9

Molecular formula:

C8H3F3N2O2

IUPAC Name:

2-nitro-4-(trifluoromethyl)benzonitrile

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Control, 1.0, 2.0, 4.0, 8.0 and 16.0 mg/L
- Sampling method: 10 mL water samples were taken at 0, 24 and 48h from the blank control group and each treatment group

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 0.0101 g test substance was weighed, dissolved with Elendt M7, subjected to ultrasound for 20 minutes and diluted to 100 mL, yielding 100 mg/L test substance stock solution.
- Controls: negative control (Elendt M7 medium)
- Test concentrations separation factor: 2

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: Batch number: D20190320D
- Age at study initiation (mean and range, SD): younger than 24 hours
- Stage and instar at study initiation: The Daphnia used in the toxicity test were healthy parthenogenetic female Daphnia, not first born.
- Source: Nanjing Institute of Environmental Sciences of the Ministry of Environmental Protection obtained in 2018
- Feeding during test: no

ACCLIMATION
- Acclimation period: Held in test facility since 2018
- Acclimation conditions (same as test or not): same

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Test temperature:

20.2 - 20.7 °C.

pH:

7.34 - 8.03

Dissolved oxygen:

6.46 - 8.60 mg/L

Nominal and measured concentrations:

Nominal concentrations: 0.0 (Control), 1.0, 2.0, 4.0, 8.0 and 16.0 mg/L
Mean measured concentrations: < LOD/LOQ, 0.973, 1.88, 3.80, 7.50 and 14.9 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL beakers (100 mL, Tianbo Instruments Factory, with breathable lid)
- Type (delete if not applicable): open
- Volume of solution: 50 mL
- Aeration: none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M7 medium was used as test medium
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH, dissolved oxygen, and temperature were measured at 0 and 48 hours.

OTHER TEST CONDITIONS
- Photoperiod: Light/dark ratio 16:8 h
- Light intensity: 1430 lux to 1476 lux

EFFECT PARAMETERS MEASURED: Immobilisation of daphnids was observed daily (0, 24, 48 h).

RANGE-FINDING STUDY
- Test concentrations: Control, 1.00 mg/L, 10.0 mg/L, 100 mg/L
- Results used to determine the conditions for the definitive study: 0% inhibition rate at 1 mg/L; 100% inhibition rate at 10 and 100 mg/L.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate was used as reference compound and tested at least once a year to verify that the test conditions satisfied the test requirements and no significant changes had occurred.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

6.55 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

3.8 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Mortality of control: Activity of young Daphnia was normal in the blank control group and in the 1.00 mg/L, 2.00 mg/L, and 4.00 mg/L test groups and no significant inhibition symptoms were apparent.
- Immobilisation: In the 8.00 mg/L and 16.0 mg/L test groups, deaths and immobilisation occurred in Daphnia.

Results with reference substance (positive control):

EC50 (48 h) = 1.23 mg/L (nominal) obtained in test from test period of 16 to 28 Feb 2019.

Any other information on results incl. tables

Table 1: Measurement Results for Stability of the Test Substance in Test Medium

Prepared concentration (mg/L)	Measured concentration (mg/L)				Mean actual measured concentration/0 h actual measured concentration
	0 h	24 h	48 h	Mean value
0.00	ND^1	ND	ND	ND	-
1.00	0.989	0.980	0.951	0.973	98.4%
2.00	1.95	1.83	1.85	1.88	96.2%
4.00	3.94	3.76	3.69	3.80	96.4%
8.00	7.55	7.48	7.46	7.50	99.3%
16.0	15.2	14.9	14.7	14.9	98.2%

¹: Concentration not detected.

 

  

Table 2: Observation Results from Actual test

Prepared concentration (mg/L)	Observation results
	24 h	48 h
Blank control	5 NB	5 NB
	5 NB	5 NB
	5 NB	5 NB
	5 NB	5 NB
1.0	5 NB	5 NB
	5 NB	5 NB
	5 NB	5 NB
	5 NB	5 NB
2.0	5 NB	5 NB
	5 NB	5 NB
	5 NB	5 NB
	5 NB	5 NB
4.0	5 NB	5 NB
	5 NB	5 NB
	5 NB	5 NB
	5 NB	5 NB
8.0	5 NB	1 D 4 NB
	5 NB	2 D 3 NB
	5 NB	5 D
	5 NB	5 D
16.0	5 D	5 D
	5 D	5 D
	5 D	5 D
	5 D	5 D

NB: normal activity.

D: dead.

 

Table 3: Validity criteria for OECD 202 (2004)

Criterion from the guideline	Outcome	Validity criterion fulfilled
In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.	In the control 0% of the daphnids were immobilized.	yes
The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.	Dissolved oxygen in the blank control group and the test treatment group was greater than 3 mg/L (minimum value: 6.46, maximum value: 8.60).	yes

 

 

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

See Table 3 in "Any other information on results incl. tables".