4'-Ethyl-3-fluorbiphenyl-4-boronic acid

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:

Feb 26 - Jun 15, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The concentrations of the test item were analysed in the duplicate test media samples from all test concentrations, in the duplicate control samples and the additional control and solvent samples, from both sampling times (0 and 72 hours).

Vehicle:

no

Details on test solutions:

Due to the low limit of water solubility of the test item, a filtrate of nominal 100 mg/L and dilutions of 1:3.2, 1:10, 1:32 and 1:100 of this filtrate were tested corresponding to following mean measured concentrations of the test item: 1.734, 0.543, 0.201, 0.0628 and 0.0202mg test item/L and a control.

Test organisms (species):

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

Details on test organisms:

Pseudokirchneriella subcapitata, Strain No. 61.81 SAG formerly known as Selenastrum capricornutum, and recently renamed as Raphidocelis subcapitata (KORSHIKOV).
Cultivated in the laboratories of ibacon; original source: "Sammlung von Algenkulturen, Albrecht-von-Haller-Institut für Pflanzenwissen-schaften, Universität Göttingen", 37073 Göttingen, Germany.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Hardness:

0.24 mmol/L

Test temperature:

21.9-22.4

pH:

7.8-9.6

Nominal and measured concentrations:

1.734, 0.543, 0.201, 0.0628, 0.0202 mg test item/L (analytical values)

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

0.091 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI: 0.082 - 0.100 mg/L

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.344 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI: 0.329 - 0360 mg/L

Results with reference substance (positive control):

72-hour EC50
0.402 mg/L Yield
0.963 mg/L Growth Rate
0.414 mg/L Biomass

Validity criteria fulfilled:

yes

Conclusions:

The influence of the test item on the growth of the freshwater green algae Pseudokirchneriella subcapitata was assessed in a static concentration-response test. The 72-hour ErC50 was calculated to be 0.344 mg test item/L and the 72-hour ErC10 value was calculated to be 0.091 mg test item/L.

Executive summary:

The purpose of this test was to determine the inhibitory effect of the test item on the growth of the freshwater green algae Pseudokirchneriella subcapitata. For this purpose, exponentially growing cultures of this unicellular green algal species were exposed to various concentrations of the test item under defined conditions. The inhibition of growth in relation to control cultures was determined over a test period of 72 hours, and thus over several algal generations.

The OECD GLP criteria were met and the methods applied are fully compliant with OECD TG 201. This study encompassed 6 treatment groups (5 dose rates of the test item, and a control) with three replicates per test concentration and six replicates for the controls. At test start 50 mL of the test concentrations were inoculated with approx. 5000 algal cells per mL test medium and defined volumes of the algal suspensions were sampled after 24, 48 and 72 for determination of cell densities by spectrophotometrical measurement.
Due to the low limit of water solubility of the test item, a filtrate of nominal 100 mg/L and dilutions of 1:3.2, 1:10, 1:32 and 1:100 of this filtrate were tested corresponding to following mean measured concentrations of the test item: 1.734, 0.543, 0.201, 0.0628 and 0.0202mg test item/L and a control.

The 72-hour ErC50 was calculated to be 0.344 mg test item/L and the 72-hour ErC10 value was calculated to be 0.0.091 mg test item/L.

Description of key information

The information for this endpoint study record was obtained from an experimental study. The OECD GLP criteria were met and the methods applied are fully compliant with OECD TG 201. The influence of the test item on the growth of the freshwater green algae Pseudokirchneriella subcapitata was assessed in a static concentration-response test. The 72-hour ErC50 was calculated to be 0.344 mg test item/L and the 72-hour ErC10 value was calculated to be 0.091 mg test item/L.

Key value for chemical safety assessment

EC50 for freshwater algae:

0.344 mg/L

EC10 or NOEC for freshwater algae:

0.091 mg/L