1-[4-(2-methylpropyl)phenyl]ethan-1-one

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)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1-[4-(2-methylpropyl)phenyl]ethan-1-one

EC Number:

254-159-8

EC Name:

1-[4-(2-methylpropyl)phenyl]ethan-1-one

Cas Number:

38861-78-8

Molecular formula:

C12H16O

IUPAC Name:

1-[4-(2-methylpropyl)phenyl]ethan-1-one

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Samples from all controls and treatment groups were taken at the test start and at the test end.

Test solutions

Vehicle:

no

Details on test solutions:

The definitive test was performed using the test item loading rate of 60 mg/L, and 2.5-fold, 6.25-fold, 15.63-fold, 39.06-fold diluted filtrates of the loading rate of 60 mg/L plus the filtrate of the control.
Appropriate amount of the test item was weighed in a glass crystallizer, quantitatively transferred into a glass vessel and filled up to full volume (without headspace) with the AAP medium. The glass vessel was tightly closed with a glass cap.
The loading rate of 60 mg/L was visually heterogeneous with visible undissolved particles. The test item loading rate and the control (the AAP medium, 35 L) were mechanically shaken for 24 h (room temperature, 50 revolutions per minute). After 24 h of mechanical shaking, the loading rate (heterogeneous) and the control were stored at room temperature for a settling phase (no shaking). After 24 h of settling phase, the loading rate was still visually heterogeneous. Therefore, the loading rate and the control were filtered through a conditioned nitrocellulose membrane filter (0.22 µm, GSTF, Millipore), [SOP/W/37]. This is a WAF-approach followed by filtering, which results in a water soluble fraction. Each filtrate was visually homogeneous and transparent. The filtrate of the loading rate of 60 mg/L was sequentially diluted with filtrate of the control to prepare the lower test item concentrations.
All exposure levels and the control were inoculated with the algal pre-culture to obtain the initial algal density of 0.01 x 106 cells/mL.

Test organisms

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Green algae
- Source (laboratory, culture collection): Unicellular freshwater green algae Pseudokirchneriella subcapitata (Reinsch) Korshikov (syn. Selenastrum capricornutum Prinz, Raphidocelis subcapitata Korshikov), specification SAG 61.81, cultured in the Institute of Industrial Organic Chemistry, Branch Pszczyna, Department of Ecotoxicology, Laboratory of Aquatic Toxicology, stock from the Culture Collection of Algae at Göttingen University, Germany.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

21.7 - 22.1 °C

pH:

7.43 - 8.81

Conductivity:

139.6 µS/cm

Nominal and measured concentrations:

Nominal: 0, filtrate of the test item loading rate of 60 mg/L and 2.5-fold, 6.25-fold, 15.63-fold,and 39.06-fold diluted filtrates of the loading rate of 60 mg/L.
Measured: < 0.18 (control); 0.73, 1.69, 4.05, 9.46, 24.54 mg/L
Analytical measured concentrations were within 89.6 – 97.5% of the initial concentrations in all treatment groups.

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flasks
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 250 ml
- Aeration: no
- Initial cells density: 1E+04
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to OECD 201
- Intervals of water quality measurement: daily

OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: no
- Photoperiod: cointinuous illumination
- Light intensity and quality: 7000 – 7494 lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : cell density after 24, 48 and 72 h
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter]Countng, indiecte spectophotometric measurements at 670 nm.

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

5.11 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

1.69 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Results with reference substance (positive control):

72 h ErC50: 3.23 mg/L

Reported statistics and error estimates:

Probit method calculations and analysis by Shapiro-Wilk’s Test on Normal Distribution, Levene’s Test on Variance Homogeneity (with Residuals), Williams Multiple Sequential t-test Procedure.