Alcohols, C14-18 and C16-18-unsatd.

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted to OECD and EC guidelines and in compliance with GLP

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Samples were taken at 24, 48 and 72 hours and the cell densities determined for each sample.
Samples were taken from the control and the 100 mg/L loading rate WAF test group from the bulk test preparation at 0 hours and from the pooled replicates at 72 hours for quantitative analysis. All samples were stored frozen prior to analysis. Duplicate samples were taken at each occasion and stored frozen for further analysis if necessary.

Vehicle:

no

Details on test solutions:

Due to the low aqueous solubility and complex nature of the test item, for the purposes of the study the test medium was prepared as a Water Accommodated Fraction (WAF) of the test item.
The range-finding test was conducted by exposing Pseudokirchneriella subcapitata cells to nominal loading rates of 10 and 100 mg/L for a period of 72 hours.
Definitive test - Based on the result of the range-finding test a "limit test" was conducted at a single loading rate of 100 mg/L to confirm that no effect on algal growth was observed.

Test organisms (species):

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

Details on test organisms:

Pseudokirchneriella subcapitata is a freshwater unicellular alga, representative of primary producers found in natural waters and can therefore be considered as an important non-target organism in freshwater ecosystems.
The test was carried out using Pseudokirchneriella subcapitata strain CCAP 278/4

Test type:

static

Water media type:

other: The culture medium was prepared using reverse osmosis purified deionized water* and the pH adjusted to 7.5 with 0.1N NaOH or HCl.

Limit test:

yes

Total exposure duration:

72 h

Test temperature:

24 ± 1 °C

pH:

Control - 0 hour = pH 8.1, 72 hour = pH 8.4
100 mg/L - 0 hour = pH 8.1, 72 hour = pH 8.5

Nominal and measured concentrations:

Range finding test - Nominal loading rates of 10 and 100 mg/L for a period of 72 hours.
Based on the result of the range-finding test a "limit test" was conducted at a single loading rate of 100 mg/L to confirm that no effect on algal growth was observed.

Details on test conditions:

sufficient master culture was added to approximately 100 mL volumes of culture media contained in conical flasks to give an initial cell density of approximately 103 cells/mL. The flasks were plugged with polyurethane foam stoppers and kept under constant agitation by orbital shaker (100 – 150 rpm) and constant illumination at 24 ± 1 C until the algal cell density was approximately 104 – 105 cells/mL.

Reference substance (positive control):

yes

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOELR

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

growth rate

Results with reference substance (positive control):

A positive control used potassium dichromate as the reference item at concentrations of 0.25, 0.50, 1.0, 2.0 and 4.0 mg/L.
Exposure conditions and data evaluation for the positive control were similar to those in the definitive test.

No Observed Effect Concentration (NOEC) based on growth rate: 0.50 mg/L
No Observed Effect Concentration (NOEC) based on yield: 0.50 mg/L
Lowest Observed Effect Concentration (LOEC) based on growth rate: 1.0 mg/L
Lowest Observed Effect Concentration (LOEC) based on yield: 1.0 mg/L

The results from the positive control with potassium dichromate were within the normal ranges for this reference item.

Validity criteria fulfilled:

yes

Conclusions:

The effect of the test item on the growth of Pseudokirchneriella subcapitata has been investigated and gave EL50 values of greater than 100 mg/L loading rate WAF. The No Observed Effect Loading Rate was 100 mg/L loading rate WAF

Description of key information

Assess the effect of the test item on the growth of the green algaPseudokirchneriella subcapitata

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

EC10 or NOEC for marine water algae:

100 mg/L

Additional information

the EC50 result above is based on a limit test and not an actual value.