2-[(2-hydroxyphenyl)methyl]phenol; 2-[(4-hydroxyphenyl)methyl]phenol; 4-[(4-hydroxyphenyl)methyl]phenol

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:

5 March 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

ISO 8692 (Water Quality - Fresh Water Algal Growth Inhibition Test with Scenedesmus subspicatus and Selenastrum capricornutum)

Deviations:

no

GLP compliance:

no

Remarks:

Tetsing was not conducted to GLP, the study was conducted in accordance with ISO test methods and the solutions were analysed after exposure. For this reason we believe the results obtained within this literature report are adequate for assessment.

Test material

Test material information

Constituent 1

Reference substance name:

2-[(2-hydroxyphenyl)methyl]phenol; 2-[(4-hydroxyphenyl)methyl]phenol; 4-[(4-hydroxyphenyl)methyl]phenol

EC Number:

908-912-9

Cas Number:

1333-16-0

Molecular formula:

C39H36O6

IUPAC Name:

2-[(2-hydroxyphenyl)methyl]phenol; 2-[(4-hydroxyphenyl)methyl]phenol; 4-[(4-hydroxyphenyl)methyl]phenol

Test material form:

solid

Sampling and analysis

Analytical monitoring:

yes

Remarks:

HPLC

Test solutions

Vehicle:

yes

Remarks:

ultrapure water

Details on test solutions:

Stock solutions were prepared by dissolving BPF (20 and 30 mg/L) in ultrapure water by mixing the solutions on a magnetic stirrer for at least 24 h. Chemicals were purchased from SigmaeAldrich (99% purity or higher). All chemicals used for toxicity testing were of analytical grade.

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

The green algae Desmodesmus subspicatus Chodat 1926 (SAG 86.81; Collection of Algal Cultures, University of Gottingen, Germany) were maintained in a nutrient solution according to Jaworski in temperature-controlled room (21 ± 1 °C) on an orbital shaker at 150 rpm, alternating 15 min agitation and 15 min resting under continuous fluorescent illumination (4000 lux).

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

tests were carried out in a temperature-controlled room maintained at 21 ± 1 °C.

Nominal and measured concentrations:

7.2, 10.0, 14.4, 17.3, 20.7, 23.3, 28.0 mg/L

Details on test conditions:

In algal growth inhibition tests, 100 mL erlenmeyer flasks containing 40 mL of tested concentrations of BPF (7.2, 10.0, 14.4, 17.3, 20.7, 23.3, 28.0 mg/L), growth medium and algae (initial concentrationwas 10^4 cells/mL, obtained from the preculture in exponential growth phase) and a control (ultrapure water, growth medium, algae) were agitated constantly.under an illumination of 7000 lux (ISO 8692, 2012). All tests were run in three replicates and repeated at least three times. After 72 h, the growth of algae was quantified by fluorometric method using a fluorescence spectrometer (Perkin Elmer, model LS55). Fluorescence of algae was measured in 10mm cuvette with continuous mixing at excitation and emission wavelengths of 450 and 680 nm, respectively. The growth rates of algae and the percentages of inhibition in comparison to the control were calculated for each tested concentration.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

other: IC20

Effect conc.:

20.3 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:

IC50

Effect conc.:

22.1 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:

other: IC80

Effect conc.:

24.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

The IC50 of the test substance to green algae was determined to be 22.1 mg/L with corrrespondening 95% confidence limits of 21.2 - 23.1 mg/L.

Executive summary:

A study was performed to assess the effect of the test item on the growth of the green alga Desmodesmus subspicatus. The method followed that as described in ISO 8692, 2012.

Expsoure of Desmodesmus subspicatus to the test item gave IC50 value of 22.1 mg/L with 95% confidence limits of 21.2 - 23.1 mg/L.