2-butyl-6-(butylamino)-1H-benz[de]isoquinoline-1,3(2H)-dione

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

24.10.2016 – 27.10.2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Experimental test result performed using standard test guidelines

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: No data
- Expiration date of the lot/batch: No data
- Purity test date: No data

RADIOLABELLING INFORMATION (if applicable)
- Radiochemical purity: No data
- Specific activity: No data
- Locations of the label: No data
- Expiration date of radiochemical substance: No data

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: No data
- Stability under test conditions: No data
- Solubility and stability of the test substance in the solvent/vehicle: No data
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: No data

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: No data
- Preliminary purification step (if any): No data
- Final dilution of a dissolved solid, stock liquid or gel: No data
- Final preparation of a solid: No data

FORM AS APPLIED IN THE TEST (if different from that of starting material) No data

OTHER SPECIFICS: No

Analytical monitoring:

no

Details on sampling:

No data

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
The stock solution 50 g/L was prepared by dissolving yellow powder in DMSO.Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. It was not possible to test higher substance concentrations due to solubility of the test substance.

- Controls: OECD medium as specified in OECD 201, used as a control and for dilution of the stock solution.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: 86.81 SAG
- Source (laboratory, culture collection): Institute of botany of the ASCR
- Age of inoculum (at test initiation): 5x103 cells/ml
- Method of cultivation: No data

ACCLIMATION
- Acclimation period: No data
- Culturing media and conditions (same as test or not): No data
- Any deformed or abnormal cells observed: No data

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Remarks on exposure duration:

±1 hour

Post exposure observation period:

No data

Hardness:

No data

Test temperature:

23°C ± 2°C

pH:

The sample at concentration 50 mg/L :
pH = 8.2 changed to pH = 7.6 during the test, Control : pH = 8.1 changed to pH = 7.5 during the test
Control + DMSO: pH = 8.1 changed to pH = 7.4 during the test

Dissolved oxygen:

No data

Salinity:

No data

Conductivity:

No data

Nominal and measured concentrations:

0, 0, 5, 10, 20, 40 and 50 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 50ml glass vessel
- Type : closed (with air-permeable stopper)
- Material, size, headspace, fill volume: 7.5 ml
- Aeration: No data
- Type of flow-through (e.g. peristaltic or proportional diluter): No data
- Renewal rate of test solution (frequency/flow rate): No data
- Initial cells density: 5x103 cells/mL
- Control end cells density: No data
- No. of organisms per vessel: No data
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): No data
- No. of vessels per vehicle control (replicates): No data

GROWTH MEDIUM
- Standard medium used: Yes

OTHER TEST CONDITIONS
- Adjustment of pH: Without adjustment
- Photoperiod: Continuous
- Light intensity and quality: 6000 lx - 8000 lx

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell counting: Electronic particle counter.
- Chlorophyll measurement: No
- Other: ErC50 was calculated using non-linear regression by the software Prism 4.0

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (K2Cr2O7)

Key result

Duration:

72 h

Dose descriptor:

other: ErC50

Remarks:

ErC50 = EC50

Effect conc.:

381.3 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CL: 147.8 – 984.0 mg/L

Details on results:

No data

Results with reference substance (positive control):

- Results with reference substance valid
- ErC50: 0.69 mg/L K2Cr2O7

Reported statistics and error estimates:

No data

Control Solution: OECD growth medium without the sample, the coefficient of variation of average growth rate in replicates during the whole test period was 1.3 % without DMSO and 0.3 % with DMSO.

Validity criteria fulfilled:

yes

Conclusions:

The median effective concentration (ErC50) for the test substance, 2-butyl-6-(butylamino)-1H-benz[de]isoquinoline-1,3(2H)-dione, in a freshwater algae Desmodesmus subspicatus was determined to be 381.3 mg/L on the basis of effects on growth rate in a 72 hour study.

Executive summary:

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance 2-butyl-6-(butylamino)-1H-benz[de]isoquinoline -1,3(2H)-dione according to OECD Guideline 201.

The test substance was dissolved in DMSO and tested at the concentrations 0, 0, 5, 10, 20, 40 and 50 mg/L. Effects on the growth rate of the organism were studied.

The median effective concentration (ErC50) for the test substance, 2-butyl-6-(butylamino)-1H-benz[de]isoquinoline-1,3(2H)-dione, in Desmodesmus subspicatus was determined to be 381.3 mg/L. Based on this ErC50 value and after comparing with CLP criteria for aquatic classification of the substance it is concluded that the substance 2-butyl-6-(butylamino)-1H-benz[de]isoquinoline-1,3(2H)-dione does not exhibit toxicity to aquatic algae (Desmodesmus subspicatus).

Description of key information

The median effective concentration (ErC50) for the test substance, 2-butyl-6-(butylamino)-1H-benz[de]isoquinoline-1,3(2H)-dione, in a freshwater algae Desmodesmus subspicatus was determined to be 381.3 mg/L on the basis of effects on growth rate in a 72 hour study.

Key value for chemical safety assessment

EC50 for freshwater algae:

381.3 mg/L

Additional information

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance 2-butyl-6-(butylamino)-1H-benz[de]isoquinoline -1,3(2H)-dione according to OECD Guideline 201. The test substance was dissolved in DMSO and tested at the concentrations 0, 0, 5, 10, 20, 40 and 50 mg/L. Effects on the growth rate of the organism were studied. The median effective concentration (ErC50) for the test substance, 2-butyl-6-(butylamino)-1H-benz[de]isoquinoline-1,3(2H)-dione, in Desmodesmus subspicatus was determined to be 381.3 mg/L. Based on this ErC50 value and after comparing with CLP criteria for aquatic classification of the substance it is concluded that the substance 2-butyl-6-(butylamino)-1H-benz[de]isoquinoline-1,3(2H)-dione does not exhibit toxicity to aquatic algae (Desmodesmus subspicatus).