5-(dithiolan-3-yl)valeric 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

Study period:

2017-02-06 - 2017-03-06

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Version / remarks:

2006-03-23;
Annex 5 corrected 2011-07-28

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

5-(dithiolan-3-yl)valeric acid

EC Number:

214-071-2

EC Name:

5-(dithiolan-3-yl)valeric acid

Cas Number:

1077-28-7

Molecular formula:

C8H14O2S2

IUPAC Name:

5-(1,2-dithiolan-3-yl)pentanoic acid

impurity 1

Reference substance name:

unknown

IUPAC Name:

unknown

impurity 2

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

dihydrogen oxide

Test material form:

solid: bulk

Details on test material:

This composition is the usual techical grade of AlzChem AG. It will be used when test substance has this composition (or is very closed) or no specific information is available

Test organisms

Test organisms (species):

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

Study design

Test type:

static

Water media type:

other: mineral medium (AAP-Medium)

Remarks:

See Annex 3 of OECD 201 "Freshwater Alga and Cyanobacteria, Growth Inhibition Test", 2011

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

22.3 - 23.0 °C

pH:

7.5 +/-0.1

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

ca. 0.583 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:

EC50

Effect conc.:

ca. 5.51 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 1.23 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 4

Key result

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

ca. 0.477 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

not specified

Remarks on result:

other: Bonferroni-Holms corrected Welch test for growth rate

Remarks:

Dunnetts-t-test for yield (left sided, p < 0.5))

Effect concentrations 5

Duration:

72 h

Dose descriptor:

NOEC

Remarks on result:

not measured/tested

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Significant inhibitory effects were determined for growth rate and for yield at test item
concentrations of 0.477 mg/L (nominal) and 0.0698 mg/L (actual) and above. The overall LOEC
was therefore determined to be 0.477 mg/L (nominal) and 0.0698 mg/L (actual), the corresponding
NOEC could not be determined.
The EC10-value for growth rate (ErC10) was determined to be 0.583 mg/L (nominal). The EC20-value
was determined to be 1.34 mg/L (nominal) and 0.213 mg/L (actual). The EC50-value for growth rate
(ErC50) was determined to be 5.51 mg/L (nominal) and 1.67 mg/L (actual). The EC50-value for yield
(EyC50) was 1.23 mg/L (nominal) and 0.186 mg/L (actual).
Since the estimated EC10 and EC20 values for yield (actual and nominal) and the EC10 for growth rate
(actual) was below the lowest test item concentration, these values are not reported.

Executive summary:

Significant inhibitory effects were determined for growth rate and for yield at test item
concentrations of 0.477 mg/L (nominal) and 0.0698 mg/L (actual) and above. The overall LOEC
was therefore determined to be 0.477 mg/L (nominal) and 0.0698 mg/L (actual), the corresponding
NOEC could not be determined.
The EC10-value for growth rate (ErC10) was determined to be 0.583 mg/L (nominal). The EC20-value
was determined to be 1.34 mg/L (nominal) and 0.213 mg/L (actual). The EC50-value for growth rate
(ErC50) was determined to be 5.51 mg/L (nominal) and 1.67 mg/L (actual). The EC50-value for yield
(EyC50) was 1.23 mg/L (nominal) and 0.186 mg/L (actual).
Since the estimated EC10 and EC20 values for yield (actual and nominal) and the EC10 for growth rate
(actual) was below the lowest test item concentration, these values are not reported.