(2S)-3-Methyl-2-[N-({2'-(1H-1,2,3,4-tetrazol-5-yl)-[1,1-biphenyl]-4-yl}methyl)pentanamido]alkanoic acid

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Apr - Aug 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

During the final test samples for possible analysis were taken from the WSF and the control according to the schedule below.
Frequency at t=O h, t=24 h and t=72 h
Volume 2ml

Vehicle:

yes

Details on test solutions:

The standard test procedures required generation of test solutions, which contained completely
dissolved test substance concentrations or stable and homogeneous mixtures or dispersions.
The testing of concentrations that would disturb the test system was prevented as much as
possible (e.g. film of the test substance on the water surface).
The batch of VALSARTAN/DS 21 tested was a white powder and the substance was not
completely soluble in test medium at the concentrations tested.
Preparation of test solutions started with a stock solution prepared at a loading rate of 100 mg/I
applying approximately 24 hours of magnetic stirring followed by a stabilisation period of
approximately 2 hours. The resulting solution was clear and colourless with a floating layer
containing minor particles extended to the border. The apparent water soluble fraction (WSF) of
the solution was then siphoned off and lower test concentrations were prepared by subsequent
dilutions in test medium. The final test solutions were all clear and colourless.
After preparation, volumes of 50 ml were added to each replicate of the respective test
concentration. Subsequently, 1 ml of an algal suspension was added to each replicate providing
a cell density of 10E4 cells/ml.

Test organisms (species):

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

Details on test organisms:

Pseudokirchneriella subcapitata, strain: NIVA CHL 1

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test temperature:

22.2 and 22. 7°C

pH:

5.5 and 5.6

Details on test conditions:

The pH was not within the limits prescribed by the protocol (protocol deviation 2). The pH of 100 mg/I VALSARTAN/DS 21-was slightly below the lower limit at the end of the test.
At the end of the range-finding and the final limit test, the pH of the WSF prepared at a loading rate of 100 mg/I was below 6.0 (5.5 and 5.6 respectively).
Evaluation: the low pH of the test group did not affect the growth as the growth in this group was comparable to or even slightly higher than that of the control in which the pH was within the optimum level. Therefore, this small pH deviation had no effect on the integrity of the study.
The study integrity was not adversely affected by the deviations.

Reference substance (positive control):

no

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: water soluble fraction

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: water soluble fraction

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: water soluble fraction

Basis for effect:

other: yield

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: water soluble fraction

Basis for effect:

other: yield

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present study with Pseudokirchneriella subcapitata, no reduction of growth rate or inhibition of yield was recorded at any of the concentrations of VALSARTAN/DS 21 tested.
The EC50 for growth rate reduction (ERC50: 0-72h) and for yield inhibition (EvCs0: 0-72h) was beyond the range tested.
The NOEC for growth rate reduction and yield inhibition was 100 mg/I.

Description of key information

Under the conditions of the present study with Pseudokirchneriella subcapitata, no reduction of growth rate or inhibition of yield was recorded at any of the concentrations of VALSARTAN/DS 21 tested.

The EC50 for growth rate reduction (ERC50: 0-72h) and for yield inhibition (EvCs0: 0-72h) was beyond the range tested.

The NOEC for growth rate reduction and yield inhibition was 100 mg/I.

Key value for chemical safety assessment

EC10 or NOEC for freshwater algae:

100 mg/L