Star anise, Illicium verum, ext.

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

Version / remarks:

OECD Guideline 201 (2011)

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(E)-anethole

EC Number:

224-052-0

EC Name:

(E)-anethole

Cas Number:

4180-23-8

Molecular formula:

C10H12O

IUPAC Name:

1-methoxy-4-prop-1-en-1-ylbenzene

Constituent 2

Reference substance name:

4-allylanisole

EC Number:

205-427-8

EC Name:

4-allylanisole

Cas Number:

140-67-0

Molecular formula:

C10H12O

IUPAC Name:

1-allyl-4-methoxybenzene

1

Reference substance name:

Caryophyllene

EC Number:

201-746-1

EC Name:

Caryophyllene

Cas Number:

87-44-5

Molecular formula:

C15H24

IUPAC Name:

4,11,11-trimethyl-8-methylenebicyclo[7.2.0]undec-4-ene

Constituent 3

Reference substance name:

2,6-dimethyl-6-(4-methyl-3-pentenyl)bicyclo[3.1.1]hept-2-ene

EC Number:

241-702-9

EC Name:

2,6-dimethyl-6-(4-methyl-3-pentenyl)bicyclo[3.1.1]hept-2-ene

Cas Number:

17699-05-7

Molecular formula:

C15H24

IUPAC Name:

2,6-dimethyl-6-(4-methylpent-3-en-1-yl)bicyclo[3.1.1]hept-2-ene

Test material form:

liquid

Sampling and analysis

Analytical monitoring:

not specified

Details on sampling:

The samples were dissolved with OECD medium resulting in a concentration of 100 mg.L1 and a series of dilutions was prepared in order to obtain the desired tested concentrations. Aliquots were filtered and used for GC-MS analysis.

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: Green algae
- Strain: SAG 61.81
- Source (laboratory, culture collection): The test system was obtained from Culture Collection of Algae at Goettingen University - SAG 61.81 on October, 08th, 2013. A stock algal culture is continuously maintained at the test facility
- Age of inoculum (at test initiation): 3 days growth

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

22.1 to 22.3 °C

pH:

7.9 - 8.2

Nominal and measured concentrations:

nominal: control, 0.32, 1.0, 3.2, 10 and 32 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL Erlenmeyer flasks
- Material, size, headspace, fill volume: glass beaker plugged with gas permeable silicone sponge caps, 100 mL fill volume
- Initial cells density: 0.5E+04 cells/mL
- Control end cells density: 68E+05
- No. of vessels per concentration (replicates): 3

GROWTH MEDIUM
- Standard medium used: yes

- Light intensity and quality: average 6.258 lux, continuous light.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: a Neubawer chamber and a microscope

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.91 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

6.18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 4

Key result

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

0.32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

The 72-hours EyC50 value of test substance Star Anise Oil (Illicium verum), obtained in this study with Pseudokirchneriella subcapitata, was 0.91 mg.L-1 (95% confidence limits = 0.77 to 1.07 mg.L-1) and the 72-hours ErC50 value was 6.18 mg.L-1 (95% confidence limits = 5.39 to 7.07 mg.L-1). The highest concentration of the test substance in which was not observed any statistically significant adverse effect on algal growth (NOEC) over the test period (72 hours) was 0.1 mg.L-1 and the lowest test substance concentration at which was observed significant reducing effect on growth (LOEC) was 0.32 mg.L-1.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- EC50: 0.65 mg/L (based on yield) (confidence limits at 95% = 0.59 to 0.71 mg.L-1)

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 72-hours EyC50 value for alga Pseudokirchneriella subcapitata exposed to Star Anise Oil (Illicium verum) was 0.91 mg.L-1 and the 72-hours ErC50 value was 6.18 mg.L-1. The highest test substance concentration with no observed significant adverse effect (NOEC) on algal growth was 0.1 mg.L-1 and the lowest test substance concentration at which was observed significant reducing effect on growth (LOEC) was 0.32 mg.L-1.

Executive summary:

The objective of this study was to evaluate the toxicity of Star Anise Oil (Illicium verum) on algaPseudokirchneriella subcapitata. A range-finding test was conducted to find the concentrations that cause algae growth inhibition. Based on the results of the range-finding test, a definitive test was carried out with the following concentrations of test substance: 0 (control); 0.1; 0.32; 1; 3.2 and 10 mg.L^-1. The test was incubated during 72 hours inside chambers with controlled conditions of luminosity, temperature, and agitation. The 72-hours E_yC₅₀value was 0.91 mg.L^-1and the 72-hours E_rC₅₀value was 6.18 mg.L^-1. The highest test substance concentration which no observed significant adverse effect (NOEC) on algal growth was 0.1 mg.L^-1and the lowest test substance concentration at which was observed significant reducing effect on growth (LOEC) was 0.32 mg.L^-1.