N-(butoxymethyl)acrylamide

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:

1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Justification for type of information:

See the Analogue Approach Report attached in Section 13 of the IUCLID dossier.

Reason / purpose for cross-reference:

other: Read across to target substance

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Green Algae
- Strain: Selenastrum capricornutum (CCAP 278/4)
- Source (laboratory, culture collection): AQUARIUM DE TROUVILLE (17 rue de Paris, 14360 TROUVILLE).
- Age of inoculum (at test initiation): approximately 72-hours
- Method of cultivation: the sub-culture used for the algal inoculation was made in the same culture medium as that used for the test, and kept under the same conditions as those employed for the test (culture medium, lighting, temperature, sting). Contemporaneously to the start of the test, pre-culture cell concentration was measured and the volume to be used for the inoculation of test and control media was determined.
ACCLIMATION
- Acclimation period: none reported
- Culturing media and conditions: same as test
- Any deformed or abnormal cells observed: none reported

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Hardness:

40 mg/L

Test temperature:

24.0-24.5°C

pH:

6.95-8.84

Dissolved oxygen:

Not reported

Nominal and measured concentrations:

Nominal : 10, 18, 32, 56 and 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: open
- Material, size, headspace, fill volume: Erlenmeyer flasks of 250 ml capacity, provided with a cotton-wool plug.
- Aeration: no
- Initial cells density: 9,600 cells per millilitre
- Control end cells density: 3,263,333 per millilitre
- No. of vessels per concentration (replicates): 3
- No. of vessels per vehicle control (replicates): 3
GROWTH MEDIUM and TEST MEDIUM
- Standard medium used: yes
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: sterile tap water
- Culture medium different from test medium: No
- Total organic carbon: 0 mg/l
- Particulate matter: 0 mg/l
- Salts: Ca(NO3)2.4 H2O = 40mg/L; KNO3 = 100mg/L, MgSO4.7 H2O = 30Mg/L; K2HPO4 = 40mg/L; CuSO4.5 H2O = 0.015mg/L; (NH4)6.Mo7O24.4 H2O = 0.030mg/L; ZnSO4.7 H2O = 0.030mg/L; CoCl2.6 H2O = 0.030mg/L; Mn(NO3)2.4 H2O = 0.030mg/L; C6H8O7.H20 = 0.030mg/L; H3BO3 = 0.030mg/L; Ammonium iron III citrate (Fe2O3 content = 29-32 %) = 0.8125mg/L; FeSO4.7 H2O = 0.3125mg/L; FeCl3.6 H2O = 0.3125mg/L
- Pesticides: none
- Chlorine: none reported
- Alkalinity: not reported
- Ca/mg ratio: not reported
- Conductivity: not reported
OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: readjusted with HCl 0.1N.
- Photoperiod: continuous white lighting
- Light intensity and quality: artificial lighting 7180 - 7230 lux
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations:24 ,48 and 72 hours after the start of the test, the cell concentration was measured for each control and test flask by direct counting of cells with microscope.
TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10, 18, 32, 56 and 100 mg

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

67.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

56 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Inhibitions íif the growth in comparison with the control group (lA as %)

Test substace nominal concentration (mg/L)	Inhibition of the cell growth (IA ) in 72 hours %
10	-30
18	- 18
32	- 15
56	43
100	64

IA (%) = [(A control - A concentration) / A control] x 100

Inhibitions of the growth rate in comparison with the control group (lµ., as %)

Test substace nominal concentration (mg/L)	Inhibition of the growth rate (Iµ) in 72 hours ( %)
10	-5
18	-3
32	-2
56	14
100	26

Iµ (%) = [(µ control - µ concentration) / µ control ] x 100

Validity criteria fulfilled:

yes

Remarks:

Cell concentration in the control group increased by a factor of at least 16 within 3 days as required: It increased by a factor of 340 during the test period.

Conclusions:

Under the test conditions the ICA50 (growth inhibition) of ACRYLAMIDE 50 ST to green algae Selenastrum capricornutum was 67.7 mg/l and the ICµ50 (growth rate inhibition) was greater than 100 mg/l. The No Observed Effect Concentration was NOEC = 32 mg/l. Therefore, for acrylamide the ICA50 (growth inhibition) is 33.85 mg/l, the ICµ50 (growth rate inhibition) is greater than 50 mg/l and the NOEC is 16 mg/l.

Description of key information

The toxicity of the read-across material, acrylamide, to aquatic algae was assessed according to OECD Test Guideline 201 using Pseudokirchneriella subcapitata. Under the test conditions the 72 hours EC50 for growth rate inhibition was greater than 100 mg/L. The 72 hour No Observed Effect Concentration was 56 mg/L.

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

EC10 or NOEC for freshwater algae:

56 mg/L

Additional information

The toxicity of the read-across material, acrylamide, to aquatic algae was assessed according to OECD Test Guideline 201 using Pseudokirchneriella subcapitata.

Algae were exposed in Erlenmeyer flasks of 250 mL capacity under static conditions with continuous lighting for 72 hours. 24, 48 and 72 hours after the start of the test, the cell concentration was measured for each control and test flask by direct counting of cells with microscope. Cell concentration in the control group increased by a factor of at least 16 within 3 days as required; it increased by a factor of 340 during the test period.

Under the test conditions the 72 hours EC50 for growth rate inhibition was greater than 100 mg/L. The 72 hour No Observed Effect Concentration was 56 mg/L.