2-nitro-4-(trifluoromethyl)benzonitrile

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 Mar – 01 May 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 211 (Daphnia magna Reproduction Test)

Version / remarks:

2012

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, 0.1, 1.6 mg/L
- Sampling method: At the start of the actual test, day 0 (fresh) to day 3 (valid), day 9 (fresh) to day 12 (valid), and day 18 (fresh) to day 21 (valid), the highest (1.6 mg/L) and the lowest concentrations (0.1 mg/L) of test substance solution concentrations were measured. Therefore, 20 mL of the treatment with a test substance concentration of 0.1 mg/L and 10 mL of the treatment with a test substance concentration of 1.6 mg/L were sampled.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 0.0101 g - 0.0102 g of the test substance NTBN was weighed and added to 100 mL Elendt M7, and dissolved fully. Different concentrations of NTBN test solution were obtained by dilution with Elendt M7; at the same time, a blank control group was established.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: Batch number: D20190410D
- Age at study initiation (mean and range, SD): less than 24 h old
- Source: Nanjing Institute of Environmental Sciences of the Ministry of Environmental Protection
- Feeding during test: yes
- Food type: Feeding was with green algae (Chlorella vulgaris Beij.) liquid concentrate
- Amount: 0.1-0.2 mg C/Daphnia each time
- Frequency: once daily
- Other information: For each testing round, the daphnia used were identical healthy parthenogenic female offspring daphnia of three generations or more cultivated in the laboratory

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Test conditions

Hardness:

205 - 226 mg (CaCO3)/L

Test temperature:

20.0 - 20.4 °C

pH:

6.91 - 7.48

Dissolved oxygen:

7.20 - 8.43 mg/L

Nominal and measured concentrations:

Nominal concentrations: 0 (Control), 0.1, 1.6 mg/L
Mean measured concentrations: < LOD/LOQ, 0.0971, 1.58 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Beaker (100 mL, Tianbo Instruments Factory, with breathable lid)
- Type (delete if not applicable): open
- Aeration: none
- Renewal rate of test solution (frequency/flow rate): Every 72 h.
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10

TEST MEDIUM / WATER PARAMETERS
- Intervals of water quality measurement: Once a week, dissolved oxygen concentration, temperature, hardness, and pH value were measured in the fresh solution and old solution of the control group and the lowest and highest test concentration groups.

OTHER TEST CONDITIONS
- Photoperiod: 16 h light per day
- Light intensity: 1000 lux to 1500 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
- Offspring: In the test period, surviving offspring Daphnia in each treatment group and control group were observed and counted daily.
- Other test parameters: First time parent Daphnia produced offspring (and subsequent times that offspring were produced) and the number of batches of offspring produced by each parent Daphnia and quantities per batch were recorded.

TEST CONCENTRATIONS
- Range finding study: yes
- Test concentrations: 0.0 (Control), 1.00 mg/L and 10.0 mg/L
- Results used to determine the conditions for the definitive study: 100% of offspring survived at 1.00 mg/L; 0% of mother daphnia survived at 10 mg/L.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

0.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 2

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 3

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

> 1.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 4

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 5

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

1.58 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 6

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1.58 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality of control: At the end of the test, there were no deaths of mother Daphnia in the blank control group and the test groups.
- Immobilisation of control: Over the test period, Daphnia magna in the control group exhibited normal activity and each surviving parent Daphnia successfully produced 96 - 127 live offspring Daphnia, the coefficient of variation for reproduction quantity for each parent Daphnia was 9.80% (less than 25%).
- Reproduction: The difference in mother Daphnia reproduction rates between the 0.80 mg/L test group and the control group was significant (p < 0.05).

Any other information on results incl. tables

Table 1: Measurement Results for Test Solution Stability in Test Medium

Prepared concentration (mg/L)	Actual measured concentration (mg/L)
	d 0	d 3	d 9	d 12	d 18	d 21	Mean
	Fresh	Valid	Fresh	Valid	Fresh	Valid
Blank control	ND	ND	ND	ND	ND	ND	-
0.1	0.0976	0.0931	0.103	0.0949	0.101	0.0931	0.0971
1.6	1.57	1.56	1.60	1.58	1.63	1.56	1.58

 ND: Lower than the method’s limit of detection.

 

  

Table 2: Actual Test Reproduction Rate Inhibitory Effects

Prepared concentration (mg/L)	Initial number of Daphnia (n)	21 d
		Mean reproduction quantity (number of surviving offspring Daphnia/ mother Daphnia)	Inhibition rate (%)
Blank control	10	106	-
0.1	10	101	4.72
0.2	10	99	6.60
0.4	10	88	17.0
0.8	10	82	22.6
1.6	10	41	61.3
LOEC (Dunnett's Test)		0.80 mg/L (prepared concentration)
NOEC (Dunnett's Test)		0.40 mg/L (prepared concentration)

 

Table 3: Validity criteria for OECD 211

Criterion from the guideline	Outcome	Validity criterion fulfilled
The mortality of the parent animals in the control (female Daphnia) does not exceed 20% at the end of the test.	At the end of the test, 100% of the parent animal in the blank control group survived and activity was normal.	yes
The mean number of living offspring produced per parent animal surviving at the end of the test is ≥ 60 in the control.	Each surviving parent Daphnia successfully produced 96 - 127 (mean reproduction quantity: 106 surviving offspring) live offspring Daphnia, the coefficient of variation for reproduction quantity among parent Daphnia was 9.80%.	yes

 

 

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

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