4,4'-azobis[4-cyanovaleric] 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)

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 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-azobis[4-cyanovaleric] acid

EC Number:

220-135-0

EC Name:

4,4'-azobis[4-cyanovaleric] acid

Cas Number:

2638-94-0

Molecular formula:

C12H16N4O4

IUPAC Name:

4,4'-azobis[4-cyanovaleric] acid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Analysis of the test media samples was conducted on fresh media at 0 hours and on corresponding old media at 72 hours. Measured test concentrations were determined from samples of test solution from each treatment and control group.

Test solutions

Vehicle:

no

Details on test solutions:

A 147 mg test substance/L solution was prepared by adding ca 296.54 mg of test substance to 2000 mL of EC medium and stirred for 1 hour (test media code = TM1). After settlement for 1 hour the test solution was removed by siphoning and the collected solution was checked for the tyndall effect using a Hach 2100 N turbidity meter. The turbidity meter confirmed that there was no dispersed test substance present and therefore the test solution was used to prepare the remaining test solutions

Test organisms

Test organisms (species):

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

Details on test organisms:

The test organism, Pseudokirchneriella subcapitata (Strain 278/4), was originally obtained from the Culture Collection of Algae and Protozoa (CCAP) and is a representative species of the freshwater aquatic phytoplankton.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Hardness:

Hardness (mg CaCO3/L)
38 and 42 (two batches used)

Test temperature:

Temperature Range (°C)
21.6 – 23.1°C

pH:

7.50 – 8.54

Salinity:

Alkalinity (mg CaCO3/L)
26 and 25 (two batches used)

Conductivity:

193 -234 μS/cm

Nominal and measured concentrations:

The measured test substance concentrations were between 84.2 – 104 % of nominal test substance concentrations at 0 hours and 92.4 - 137 % of nominal concentrations at 72 hours.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 147 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other:

Remarks:

pH adjusted

Effect concentrations 2

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 147 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other:

Remarks:

pH adjusted

Details on results:

The 72-hour EyC50, EbC50 and ErC50 values based on nominal test substance concentrations were estimated to be 93.0, 93.3 and 86.2 mg/L when not pH adjusted and >147 mg/L when pH adjusted.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes