4-chlorobenzonitrile

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10.06.2014 - 09.07.2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Analytical samples were taken from all test concentrations and control vessels at test start, at renewal of test solutions and 48 hours after beginning of the test. No analytical samples were taken after 24 hours from fresh test solutions and after 48 hours from aged test solutions from 100 and 50.0 mg/L, as all daphnids died within the first 24 hours.
Samples from all test item concentrations and the control taken at t = 0 and at t = 24 hours from aged test solutions were analysed. Samples from control and the test item concentrations 25.0, 12.5 and 6.25 mg/L taken at t= 24 hours from fresh test solutions were analysed.

Vehicle:

no

Details on test solutions:

Elendt M4 medium was used as test medium (composition and preparation according to OECD 202). At test initiation the pH-value of the control (untreated test medium) was 7.90, the dissolved oxygen concentration was 8.7 mg/L and the total hardness was 14°dH (250 mg/L as CaCO3).

The daphnids were exposed to increasing concentrations of the test item for 48 hours, with a renewal of the test solutions after 24 hours. A control was tested in parallel. Two concentrations of the reference item potassium dichromate (1.0 mg/L, 2.0 mg/L) were tested around the same time period as the study.

The concentrations in the main test were spaced by a factor of 2.0. The necessary amount of 4-Chlorobenzonitrile for preparing the stock solution was weighed on weighing scoops and transferred to a volumetric flask. Test medium was added up to the bench mark and the solution was homogenised by 10 minutes ultrasonification, followed by stirring for 24 hours in the dark at room temperature. The lower test solutions were prepared by dilution of the stock solution. Defined volumes of the prepared solution were transferred to each test vessels. The test solution volume was 50 mL per test vessel.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Strain: Daphnia magna Straus, Clone V
- Source: Umweltbundesamt, Berlin, Germany
- Age at study initiation: freshly hatched, max. 24 hours old
- Method of breeding: Daphnia magna was bred as group culture (5 to 20 daphnids per litre) in Elendt M4 medium. The pH-value of the aerated water was within a range of 6.0 – 9.0. The dissolved oxygen was above 60 % saturation and the total hardness 140 - 250 mg/L (as CaCO3), corresponding to 7.8 - 14°dH. The animals were fed with single cell green algae (Desmodesmus subspicatus, former Scenedesmus subspicatus) at least three times a week.
- Feeding during test: none
- Food type: single cell green algae (Desmodesmus subspicatus)
- Frequency: at least three times a week

ACCLIMATION
Not necessary because the daphnids were bred in the laboratory under the same conditions as in the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

Not applicable

Hardness:

14 °H (250 mg/ as CaCO3)

Test temperature:

20 - 21.3 °C

pH:

7.55 - 8.06

Dissolved oxygen:

>= 8.5 mg/L

Salinity:

Not applicable.

Nominal and measured concentrations:

Nominal Concentration: 0, 6.25, 12.5, 25.0, 50.0, 100 mg/L
Measured Concentration (after 0 h fresh): 5.05, 12.0, 24.3, 49.8 99.2 mg/L
Measured Concentration (after 24 h aged): 0.828, 2.78, 9.36, 23.1, 47.3 mg/L
Measured Concentration (after 24 h fresh): 4.75, 12.1,24.5, further samples not taken since all daphnids were immobilised after 24 hours

Details on test conditions:

TEST SYSTEM
- Test vessel: four 100 mL glass beakers per concentration, each filled with 50 mL
- Aeration: none
- Test type: semi-static
- 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: deionised water

OTHER TEST CONDITIONS
- Adjustment of pH: pH = 7.55 - 8.06
- Photoperiod: 16 h of illumination and 8 h darkness

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.0

RANGE FINDING TEST:
The non-GLP range finding test was conducted with the following concentrations: 0, 0.10, 1.00 and 10.0 mg/L. As no immobilisation above the allowed control immobilisation of 10 % was observed up to 10.0 mg/L, the main test concentrations were chosen to be 0, 6.25, 12.5, 25.0, 50.0 and 100 mg/L.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

16.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

8.06 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

6.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

2 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Results with reference substance (positive control):

In order to check the validity of the results, the toxicity of the reference item potassium dichromate was tested at 1.0 and 2.0 mg/L with 20 test organisms per test concentration on 10 Jun 2014 around the same time period as the study with the test item. The results indicate an EC50 (24 h) of the reference item potassium dichromate between 1.0 and 2.0 mg/L. Since the results fall within the range recommended by the guideline (OECD 202), the daphnids were suitable for the determination of the toxicological effects of the test item.

Validity criteria fulfilled:

yes

Conclusions:

According to the results of the test, the EC50 (48 h) for immobilisation was determined to be 16.1 mg/L (nominal) and 8.06 mg/L (actual) of test item. The corresponding NOEC (48 h) was 6.25 mg/L (nominal) and 2.02 mg/L (actual) of 4-Chlorobenzonitrile.

Executive summary:

The toxicity of 4 -Chlorobenzonitrile on Daphnia magna was tested in a 48 hour acute immobilisation test. The test was performed semi-static according to OECD Guideline 202 ("Daphnia sp., Acute Immobilisation Test") with concentrations of 0, 6.25, 12.5, 25.0, 50.0 and 100 mg/l and twenty organisms per test concentration (4 replicates of 5 animals each) were used.

According to the results of the test, the EC50 (48 h) for immobilisation was determined to be 16.1 mg/L (nominal) and 8.06 mg/L (actual) of test item. The corresponding NOEC (48 h) was 6.25 mg/L (nominal) and 2.02 mg/L (actual) of test item.

The EC50 (48 h) of 16.1 mg/L (nominal) was taken for classification and labeling because it does not make sense to take the actual value as this value is only an indication for the accumulation in the biosystem.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

QSAR prediction: migrated from IUCLID 5.6

Qualifier:

no guideline followed

Principles of method if other than guideline:

QSAR; calculation on basis of log Kow using EPISUITE 3.12 (US-EPA 2004); further reported QSAR calculation based on physico-chemical data of 4-chlorobenzonitrile (details not reported); in addition the EC50 was derived by QSAR extrapolating the EC50 of 4-chlorobenzonitrile for Vibrio fisheri to Daphnia magna.

GLP compliance:

no

Test organisms (species):

Daphnia sp.

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

66 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks on result:

other: EPISUITE calculation based on log Kow = 2.24

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

13 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks on result:

other: calculation based on physico-chemical parameters (original reference: Zhao & Wang, 1995. Quantitative structure-activity relationships of hydrophobic organic chemicals. Toxicol. Environ. Chem. 50, 167-172)

Dose descriptor:

EC50

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks on result:

other: Extrapolation of EC50 value of 4CBN for V. fisheri to D. magna (Zhao et al., 1995. Predicting toxicities of substituted aromatic hydrocarbons to fish by toxicities to Daphnia magna or Photobacterium phosphoreum. Toxicol. Environ. Chem. 51, 191-195)

Validity criteria fulfilled:

not applicable

Conclusions:

The QSAR calculated EC50 values of 4-chlorobenzonitrile for Daphnia range between 10 mg/L and 66 mg/L.

Executive summary:

As no experimental data are available the 48-h EC50 of 4-chlorobenzonitrile for Daphnia was calculated using EPISUITE 3.12 (US-EPA 2004). The calculated 48-h EC50 is 66 mg/L.

An other reported QSAR calculation based on physico-chemical data of 4-chlorobenzonitrile resulted in an 24 -h EC50 of 13 mg/L.

In addition an EC50 of 10 mg/L was derived by QSAR extrapolation of the EC50 of 4-chlorobenzonitrile for Vibrio fisheri to Daphnia magna.

Description of key information

Due to the results of a test according to OECD 202, the EC50 (48 h) of 4-Chlorobenzonitrile for immobilisation was determined to be 16.1 mg/L (nominal) and 8.06 mg/L (actual) of test item. The corresponding NOEC (48 h) was 6.25 mg/L (nominal) and 2.02 mg/L (actual).
Furthermore EC50 values of 4-Chlorobenzonitrile for Daphnia in a range between 10 mg/L and 66 mg/L were calculated with different QSAR models.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

16.1 mg/L

Additional information

The toxicity of 4 -Chlorobenzonitrile on Daphnia magna was tested in a 48 hour acute immobilisation test. The test was performed semi-static according to OECD Guideline 202 ("Daphnia sp., Acute Immobilisation Test") with concentrations of 0, 6.25, 12.5, 25.0, 50.0 and 100 mg/l and twenty organisms per test concentration (4 replicates of 5 animals each) were used.

According to the results of the test, the EC50 (48 h) for immobilisation was determined to be 16.1 mg/L (nominal) and 8.06 mg/L (actual) of test item. The corresponding NOEC (48 h) was 6.25 mg/L (nominal) and 2.02 mg/L (actual) of test item.

Also the 48-h EC50 of 4 -Chlorobenzonitrile for Daphnia was calculated using EPISUITE 3.12 (US-EPA 2004). The calculated 48-h EC50 is 66 mg/L.

An other reported QSAR calculation based on physico-chemical data of 4 -Chlorobenzonitrile resulted in an 24-h EC50 of 13 mg/L.

In addition an EC50 of 10 mg/L was derived by QSAR extrapolation of the EC50 of 4-chlorobenzonitrile for Vibrio fisheri to Daphnia magna.