1-bromo-4-fluorobenzene

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:

29-08-2017 to 01-09-2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Experimental test result performed using standard test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Principles of method if other than guideline:

Aim of this study was to evaluate the nature of chemical when comes in contact with the test organism. Test was conducted according to the OECD guideline 201.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Remarks:

Acetone

Details on test solutions:

The solution 10.0g/l was prepared by dissolving colourless liquid in acetone. Test concentration 100.0 mg/l was prepared by mixing the stock solution of the test sample with OECD growth medium.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Common name: green algae
- Strain: 86.81 SAG
- Source (laboratory, culture collection): Institute of botany of the ASCR
- Initial biomass concentration: 5x10(3) cells /ml
- Method of cultivation: No data available

ACCLIMATION - No data available

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test temperature:

23±2°C

pH:

the sample at concentration 100.0 mg.I'1: pH = 7.9 changed to pH = 7.3 during the test,
control: pH = 8.0 changed to pH = 7.7 during the test
control + acetone: pH =7.9 changed to pH = 7.4 during the test

Nominal and measured concentrations:

100 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: 50 ml Glass vessel
- Type : closed
- Sample volume: 15 ml
- Initial cells density: 5x10(3) cells/ml
- No. of vessels per concentration (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: Continuous
- Light intensity and quality: 6000-8000 lx

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: microscope with counting chamber Cyrus I or electronic particle counter.
- 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:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: at nominal concentration 100 mg/l 2.8% growth inhibition was observed

Results with reference substance (positive control):

- Results with reference substance valid
- EC50: 0.77 mg/L (24 hours)

Reported statistics and error estimates:

EC50 was calculated using non linear regression by the software Prism 4.0

Validity criteria fulfilled:

yes

Conclusions:

Based on the growth rate inhibition of algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the exposure of chemical the EC50 was determine to be >100 mg/l.

Executive summary:

Aim of this study was to evaluate the nature of chemical test chemical when comes in contact with the test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus). Test was conducted according to the OECD guideline 201.

The solution 10.0g/l was prepared by dissolving colourless liquid in acetone. Test concentration 100.0 mg.l'1 was prepared by mixing the stock solution of the test sample with OECD growth medium. est solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture.nominal concentration 100 mg/l were used.With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. Effect on the growth of algae was determine after an exposure period of 72 hrs. The median effective concentration (EC50) for the test substance , in algae was determined to be >100 mg/L , at nominal concentration 2.8% growth inhibition was observed on the basis of growth rate inhibition effects in a 72 hour study. Based on the EC50 value, which indicates that the substance is likely to benon-hazardous to aquatic algae and cannot as per the CLP classification criteria.

Description of key information

Aim of this study was to evaluate the nature of test chemical 1-bromo-4-fluorobenzene when comes in contact with the test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus). Test was conducted according to the OECD guideline 201. The stock solution 10 g/l was prepared by dissolving colourless liquid in acetone. Test concentration 100 mg/l was prepared by mixing the stock solution of the test sample with OECD growth medium. Test performed at limit dose 100 mg/l. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, the differences in means of control and sample were estimated by the t-test for independent groups at a 95 % confidence level, all individual replicates were used (STATISTICA CZ – data analysis software system, version 9.0, StatSoft, Inc.). Statistically significant differences are for p < 0.05.. Effect on the growth of algae was determine after an exposure period of 72 hrs. Based on the growth rate inhibition of algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the exposure of chemical 1-bromo-4-fluorobenzene for 72 hrs, only 2.8 % inhibition were observed at limit dose 100 mg/l. On that basis, it can be concluded that IC50 was > 100 mg/l. Based on the above conclusion, it was consider that substance is likely to be non-hazardous to aquatic algae and cannot be classified in toxic category as per the CLP classification criteria.

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

Additional information

Aim of this study was to evaluate the nature of test chemical 1-bromo-4-fluorobenzene when comes in contact with the test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus). Test was conducted according to the OECD guideline 201. The stock solution 10 g/l was prepared by dissolving colourless liquid in acetone. Test concentration 100 mg/l was prepared by mixing the stock solution of the test sample with OECD growth medium. Test performed at limit dose 100 mg/l. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, the differences in means of control and sample were estimated by the t-test for independent groups at a 95 % confidence level, all individual replicates were used (STATISTICA CZ – data analysis software system, version 9.0, StatSoft, Inc.). Statistically significant differences are for p < 0.05.. Effect on the growth of algae was determine after an exposure period of 72 hrs. Based on the growth rate inhibition of algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the exposure of chemical 1-bromo-4-fluorobenzene for 72 hrs, only 2.8 % inhibition were observed at limit dose 100 mg/l. On that basis, it can be concluded that IC50 was > 100 mg/l. Based on the above conclusion, it was consider that substance is likely to be non-hazardous to aquatic algae and cannot be classified in toxic category as per the CLP classification criteria.