3,3-dimethylbutanone

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:

72h

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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 (Alga, Growth Inhibition Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3,3-dimethylbutanone

EC Number:

200-920-4

EC Name:

3,3-dimethylbutanone

Cas Number:

75-97-8

Molecular formula:

C6H12O

IUPAC Name:

3,3-dimethylbutan-2-one

Test material form:

solid: crystalline

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Details on test solutions:

The test organism was grown and hold in OECD medium which was used also for preparing test item solutions.
The stock solution was prepared by measuring 0.450 ml of test item into 2 000 ml OECD growth medium. The dissolution of the test item was promoted by stirring for some minutes. The density of the test item is 0.803 g/ml so the nominal concentration of stock solution was 180.68 mg/L.

Test organisms

Test organisms (species):

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

Details on test organisms:

Test species: Pseudokirchneriella subcapitata (Korshikov) F.Hindák (formerly known as Selenastrum capricornutum and Raphidocelis subcapitata)
Source: Culture Collection of Algae and Protozoa, Scottish Marine Institute (www.ccap.ac.uk)
Batch: CCAP 278/4
Date of arriving: 27 October 2017

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Test temperature:

The temperature during the test remained in the 21 ± 2 °C range. The temperature data were harvested by Extech SD200 datalogger.Throughout the test the temperature was nearly constant.

pH:

At the beginning of the test the pH values were measured in the remaining test solution of the concurrent test vessels at each dilution level.
At the end of the test the pH values were measured in each test vessel. The pH of test solutions was not adjusted at the beginning of the test.

Nominal and measured concentrations:

The toxic property of test item was investigated at five concentrations which were prepared by different dilutions of stock solution of test item. OECD medium was used for dilution of stock solution. In the test the following calculated concentrations were applied: 67.76; 90.34; 112.93; 158.10 and 180.68 mg/L.

Details on test conditions:

Preparation and breeding of inoculum culture: The inoculum culture (IN20/010) was prepared two days before starting the test and it was bred in incubator at 21 ± 2 °C. At the end of incubation, the cell density of the inoculum culture was determined with a Bürker chamber. The cell concentration was 3 250 000 cell/ml

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

74.14 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC20

Effect conc.:

85.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

112.32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

The average specific growth rate is a response variable which is calculated on the basis of the logarithmic increase of alga biomass during the test, expressed per day. The effective concentrations for growth rate are signed as ErCx. The ErCx values were determined including the 95 % confidence interval with Probit analysis using linear max. Likelihood regression. The ErC10, ErC20 and ErC50 were calculated for at both 24 and 48 h period

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Acute toxic effect of Pinacolone was investigated in Freshwater Alga and Cyanobacteria, Growth Inhibition Test (according to OECD 201 guideline).
EC50 for 72 h: 112.32 mg/L According to the Council Regulation (EC) 440/2008 Pinacolone is not hazardous to the aquatic environment [48 h EC50 (for algae or other aquatic plants) > 100 mg/L