3-(5,5,6-trimethylbicyclo[2.2.1]hept-2-yl)cyclohexan-1-ol

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

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:

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the test substance according to OECD Guideline 201.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Remarks:

Acetone

Details on test solutions:

The stock solution was prepared by dissolving colourless dense liquid in acetone. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture.

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
- Acclimation period:
- Culturing media and conditions (same as test or not):
- Any deformed or abnormal cells observed:

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Remarks on exposure duration:

±1 hour

Test temperature:

23±2°C

pH:

Without adjustment, the sample at test concentration 68 mg/l : pH = 8.2 changed to pH = 8.1 during the test.
Control: 8.2 (changed to 8.6 during test)

Nominal and measured concentrations:

0, 2, 4, 8.5, 16, 32 and 68 mg/L nominal test concentrations

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 ml Glass vessel
- Type (delete if not applicable): closed (with air permeable stopper)
- Sample volume: 30 ml
- Initial cells density: 5x10(3) cells/ml
- No. of vessels per concentration (replicates): 3
- Other:
Control solution: OECD growth medium without the sample, the coefficient of variation of average growth rate in replicates during the whole test period was 0.5% without acetone and 0.3% with acetone.

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:

other: ErC50

Effect conc.:

47 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CL: 37.3 - 59.1

Results with reference substance (positive control):

Results with reference substance valid
- ErC50: 0.65 mg/L

Reported statistics and error estimates:

ErC50 was calculated using non linear regression by the software Prism 4.0

Validity criteria fulfilled:

yes

Conclusions:

The median effective concentration (ErC50) of the test substance on Desmodesmus subspicatus was determined to be 47.0 mg/L on the basis of effects on growth rate of algae in a 72 hour study.

Executive summary:

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to the OECD Guideline 201. The stock solution was prepared by dissolving colourless dense liquid in acetone. Test solutions  of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. Conc. of test chemical used for the study were 0, 2, 4, 8.5, 16, 32 and 68 mg/L, respectively. The test was performed under static conditions in a static fresh water system at a temp. of 23±2°C. Initial cell density of test organism used was 5x10(3) cells/ml. Determination of cell counting involve the use of microscope with counting chamber Cyrus I or electronic particle counter. ErC50 was calculated using non-linear regression by the software Prism 4.0. The median effective concentration (ErC50) of the test substance on green algae Desmodesmus subspicatus was determined to be 47.0 mg/L on the basis of effects on growth rate in a 72 hour study. Thus, based on this value, test chemical can be considered as toxic to aquatic organisms and thus can be classified as aquatic chronic category 3 as per the CLP classification criteria.

Description of key information

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to the OECD Guideline 201. The stock solution (32 g/L) was prepared by dissolving colourless dense liquid in acetone. Test solutions  of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. Conc. of test chemical used for the study were 0, 2, 4, 8.5, 16, 32 and 68 mg/L, respectively. The test was performed under static conditions in a static fresh water system at a temp. of 23±2°C. Initial cell density of test organism used was 5x10(3) cells/ml. Determination of cell counting involve the use of microscope with counting chamber Cyrus I or electronic particle counter. ErC50 was calculated using non-linear regression by the software Prism 4.0. The median effective concentration (ErC50) for the test substance in Desmodesmus subspicatus was determined to be 47.0 mg/L on the basis of effects on growth rate in a 72 hour study. Thus, based on this value, test chemical can be considered as toxic to aquatic organisms and thus can be classified as aquatic chronic category 3 as per the CLP classification criteria.

Key value for chemical safety assessment

EC50 for freshwater algae:

47 mg/L

Additional information

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance according to the OECD Guideline 201. The stock solution (32 g/L) was prepared by dissolving colourless dense liquid in acetone. Test solutions  of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. Conc. of test chemical used for the study were 0, 2, 4, 8.5, 16, 32 and 68 mg/L, respectively. The test was performed under static conditions in a static fresh water system at a temp. of 23±2°C. Initial cell density of test organism used was 5x10(3) cells/ml. Determination of cell counting involve the use of microscope with counting chamber Cyrus I or electronic particle counter. ErC50 was calculated using non-linear regression by the software Prism 4.0. The median effective concentration (ErC50) for the test substance in Desmodesmus subspicatus was determined to be 47.0 mg/L on the basis of effects on growth rate in a 72 hour study. Thus, based on this value, test chemical can be considered as toxic to aquatic organisms and thus can be classified as aquatic chronic category 3 as per the CLP classification criteria.