2-Propenamide, N-(2-hydroxyethyl)-

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:

28 June 2006 and 24 July 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch number: 050804
Purity: >99%

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 4.27, 9.39, 20.7, 45.5 and 100 mg/L
- Sampling method: At the start of the definitive test, two samples (20 mL) were taken from the freshly-prepared control and test media. After 72 hours, the contents of replicate flasks from each group were pooled and further samples taken for analysis.
- Sample storage conditions before analysis: stored refrigerated

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test media was prepared from an aqueous solution in which the test substance (100 mg) was added directly to algal culture medium (1 L). An aliquot (1.26 mL) of the secondary algal inoculum was added to a portion (300 mL) of the test medium at each concentration, to give an initial cell density of 1E+04 cells/mL. An aliquot (100 mL) of the appropriate inoculated test medium was added to each of the test vessels.

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Pseudokirchneriella subcapitata
- Strain: Strain No. CCAP 278/4.
- Source (laboratory, culture collection): Culture Collection of Algae and Protozoa (CCAP), SAMS Research Services Ltd., Dunstaffnage Marine Laboratory, Dunbeg, Oban, Argyll, Scotland
- Age of inoculum (at test initiation): 3 days
- Method of cultivation: Sterile algal nutrient medium was inoculated with cells aseptically removed from the slope culture; these primary liquid cultures (100 ml) were incubated for approximately three days in an orbital incubator under continuous illumination at nominal temperatures in the range 21 to 25°C.

ACCLIMATION
- Acclimation period: 3days
- Culturing media and conditions (same as test or not): same
- Any deformed or abnormal cells observed: no

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test temperature:

22.6 to 23.7°C

pH:

7.65 to 9.83

Nominal and measured concentrations:

Nominal concentrations: 4.27, 9.39, 20.7, 45.5 and 100 mg/l;
Measured concentrations: 4.17, 9.24, 20.7, 43.9 and 96.6 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type : closed
- Material, size, headspace, fill volume: 250 ml conical flasks
- Aeration:
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate): no
- Initial cells density: 1E+04
- Control end cells density:
- No. of organisms per vessel:
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3
- No. of vessels per vehicle control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes
- Detailed composition if non-standard medium was used:

OTHER TEST CONDITIONS
- Sterile test conditions: yes/no
- Adjustment of pH: no
- Photoperiod: continuous illumination
- Light intensity and quality: 6550 lux by 6X30 W "cool white" 1 metre fluorescent tubes.
- Salinity (for marine algae):

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter] Samples were taken from control and test flasks at 24, 48 and 72 hours and the cell densities measured using a Coulter counter.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Justification for using less concentrations than requested by guideline:
- Range finding study
- Test concentrations: 1, 10, 100 mg/L
- Results used to determine the conditions for the definitive study:

Reference substance (positive control):

no

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 96.6 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

- Observation of abnormalities (for algal test): no
- Other: The measurements of water quality (temperature and pH) in control and test flasks remained within acceptable limits throughout the study.

Validity criteria fulfilled:

yes

Conclusions:

After 72 hours of exposure to HEAA, the EbC50 and ErC50, could not be identified but must be >96.6 mg/l.
The “no observed effect concentration” (NOEC) for both area under the growth curve and growth rate was 20.7 mg/l.

Executive summary:

The effect of HEAA on the growth of the green alga was assessed under non-axenic conditions. The study was conducted in accordance with OECD Guideline 201, under GLP.

After 72 hours of exposure to HEAA, the EbC50 and ErC50, could not be identified but must be >96.6 mg/l. The “no observed effect concentration” (NOEC) for both area under the growth curve and growth rate was 20.7 mg/l.

Description of key information

After 72 hours of exposure to HEAA, the EbC50 and ErC50, could not be identified but must be >96.6 mg/l. The “no observed effect concentration” (NOEC) for both area under the growth curve and growth rate was 20.7 mg/l.

Key value for chemical safety assessment

EC50 for freshwater algae:

96.6 mg/L

EC10 or NOEC for freshwater algae:

20.7 mg/L

Additional information

The effect of HEAA on the growth of the green alga was assessed under non-axenic conditions. The study was conducted in accordance with OECD Guideline 201, under GLP.

After 72 hours of exposure to HEAA, the EbC50 and ErC50, could not be identified but must be >96.6 mg/l. The “no observed effect concentration” (NOEC) for both area under the growth curve and growth rate was 20.7 mg/l.