3,5-DICARBOXYPHENYLBORONIC ACID

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

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

A deviation 1 to the study plan was made since the test item storage temperature was not recorded at some points due to temperature probe connexion failure. There was no impact since analytical measurement was performed during the test.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

5-(dihydroxyboranyl)benzene-1,3-dicarboxylic acid

Cas Number:

881302-73-4

Molecular formula:

C8H7BO6

IUPAC Name:

5-(dihydroxyboranyl)benzene-1,3-dicarboxylic acid

Test material form:

solid

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

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

Details on test organisms:

The Pseudokirchneriella subcapitata stock culture was maintained at 4°C, according to supplier recommendation, and regularly transferred to fresh medium at the laboratory. The algal stock culture was provided by the CCAP (Culture Collection of Algae and Protozoa), reference CCAP 278/4.
A pre-culture was prepared from the stock culture and maintained in an exponential growth by successive transfers to fresh medium used in the test (OECD medium) every 3 to 4 days.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

21 to 24°C controlled at ± 2°C

Nominal and measured concentrations:

Nominal concentrations (mg test item.L-1): 0 2.6 6.4 16 40 100
Measured concentrations (mg test item.L-1): 0 2.3 5.8 15.1 38 95.9
Since the deviation between the measured concentrations and the nominal concentrations was within the range of ± 20 %, analysis of the results was based in the nominal concentrations.

Details on test conditions:

continuous illumination between 4440 and 8880 lux

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.:

ca. 89.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

ca. 100 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.:

ca. 40 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Results with reference substance (positive control):

Potassium dichromate:
*EC-72h-50 (mg.L-1): 1.09
*95% confidence limits (mg.L-1): 0.95 – 1.23
*Starting date: 04/05/2020

Any other information on results incl. tables

Validity criteria are met.

                                                                                                                                                                       Actual value       Reference value       Compliance

Growth multiplication factor in the control within the 72-hour test period                                                           300                     <16                        Y

Coefficient of variation of the average specific growth rates in the control during the whole test period               2.83                    <7                         Y

Mean coefficient of variation for section-by-section specific growth rates (days 0-1, 1-2 and 2-3) in the control 10.52               <35                      Y

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

NOEC (growth rate):       40 mg.L-1
LOEC (growth rate):       100 mg.L-1

Executive summary:

The objective of this study was to assess the effects of test item 3,5-DICARBOXYPHENYLBORONIC ACID on the growth of Pseudokirchneriella subcapitata over a period of 72 hours according to OECD 201 Guideline. Pseudokirchneriella subcapitata is a freshwater green algae that is recommended by the OECD Guideline 201.

The test item is a soluble product under the test conditions and the test solutions were prepared in the test medium by dilution of a primary stock solution of test item.

The effects of 3,5-DICARBOXYPHENYLBORONIC ACID at the definitive nominal concentrations of 0; 2.6; 6.4; 16.0; 40.0 and 100.0 mg test item.L-1 to Pseudokirchneriella subcapitata were investigated under laboratory conditions.

The analytical samples were sampled at the beginning of the test and at the end of the test (72 hours) with the content of the vessels pooled and homogenized.

Since the deviation between the measured concentrations and the nominal concentrations was within the range of ± 20 %, analysis of the results were based in the nominal concentrations.

                           3,5-DICARBOXYPHENYLBORONIC ACID

NOEC

(growth rate)       40 mg.L-1

LOEC

(growth rate)       100 mg.L-1

NOEC

(yield)                  40 mg.L-1

LOEC

(yield)                  100 mg.L-1

72h-ErC10

(95% confidence limits)       74.5 mg.L-1 (95% confidence limits:45.6 – 78.5 mg.L-1)

72h-ErC20

(95% confidence limits)       79.8 mg.L-1 (95% confidence limits: 54.3 – 83.3 mg.L-1)

72h-ErC50

(95% confidence limits)       89.6 mg.L-1 (95% confidence limits: 73.4 – 92.5 mg.L-1)

72h-EyC10

(95% confidence limits)       90.7 mg.L-1 (95% confidence limits: 40 – 100 mg.L-1)

72h-EyC20

(95% confidence limits)       91.7 mg.L-1 (95% confidence limits: 40 – 100 mg.L-1)

72h-EyC50

(95% confidence limits)       93.5 mg.L-1 (95% confidence limits: 40 – 100 mg.L-1)

EC = Effect concentration

EC = Effect concentration

NOEC= No Observed Concentration

LOEC = Lowest Observed Effect Concentration