Registration Dossier

Diss Factsheets

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

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:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Version / remarks:
1996
GLP compliance:
yes
Specific details on test material used for the study:
Source; Wako Pure Chemical Ind.,
Purity: 97.2%
Analytical monitoring:
yes
Vehicle:
no
Details on test solutions:
The  medium dissolved  by the material, and the examination field liquid of 2,000 mg/L  is adjusted, in additon the filtration sterilisation was done with 0.45 um membrane filter. 
Test organisms (species):
Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)
Details on test organisms:
Strain Number: Selenastrum capricornutum ATCC22662
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
72 h
Test temperature:
23.2 - 23.7 °C 
pH:
7.9 -10.4
Dissolved oxygen:
Not applicable
Salinity:
Not applicable
Nominal and measured concentrations:
25.6, 64.0, 160, 400 and 1,000 mg/L - nominal
24.4, 61.3, 153, 401, and 1020 mg/L -TWM measured.
-Measured Concentrations (as mg/L): n. d. (<5.00) for control,  22.9-26.0 for the nominal concentration of 25.6, 57.1-65.7 for the nominal concentration of 64.0, 144-162 for the nominal concentration of 160, 391-410 for the nominal concentration of 400, and 994-1,020 for the nominal concentration of 1,000.
Details on test conditions:
Test Conditions: 
- Test Medium: OECD medium 
- Exposure Vessel Type: 100 ml-medium in a 500 ml-erlenmeyer flask  with a silicon cap which allow ventilation 
- Stock Solutions Preparations and Stability: The  medium dissolved  by the material, and the examination field liquid of 2,000 mg/L  is adjusted, in additon the filtration sterilization was done  with 0.45 um membrane filter. 
- Number of Replicates: Triplicate 
- Initial Cell Number: 10000 cells/mL 
- Water Temperature Range: 23.2 - 23.7 degree C 
- Light Condition: 4200 - 4500 lux, continuous
Key result
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
345 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Key result
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
160 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Details on results:
See Table 3 and Table 4.
Reported statistics and error estimates:
-Statistical Method: 
a) Data Analysis: Least squares method for EC, Dunnett test for NOEC 
b) Method of calculating mean measured concentrations: Time-weighted means

                                   

Table 4

Growth inhibition of Selenastrum capricornutum during 72 hrs exposure 2-Hydroxyethyl methacrylate

Nominal conc.

(mg/l

No.

Area

(*10.000)

(0-72 hours)

Inhibition

(%)

(0-72 hours)

Control

1

1860

-

 

2

1460

-

 

3

1530

-

 

Average

1620

 

25.6

1

1890

-17.0

 

2

1500

7.31

 

3

1860

-15.2

 

Average

1750

-8.29

64.4

1

1830

-12.8

 

2

1050

35.1

 

3

1730

-6.88

 

Average

1540

5.11

160

1

1670

-2.89

 

2

1580

2.54

 

3

1590

1.55

 

Average

1610

0.398

400

1

756

53.3

 

2

661

59.2

 

3

707

56.3

 

Average

708

56.3

1000

1

80.9

95.0

 

2

94.0

94.2

 

3

95.9

94.1

 

Average

90.3

94.4

 


Table 4

Cell density of Selenastrum capricornutum during 72 hrs exposure 2-Hydroxyethyl methacrylate

Nominal conc.

(mg/l

Cell density (+ 10000 cell/ml)

No.

0 hrs

24 hrs

48 hrs

72 hrs

Control

1

1.0

4.8

29.4

91.4

 

2

1.0

4.0

25.7

67.8

 

3

1.0

5.0

23.9

74.9

 

Average

1.0

4.6

26.3

78.0

 

SD

0.0

0.5

2.8

12.2

25.6

1

1.0

3.8

29.9

95.4

 

2

1.0

3.7

25.6

71.5

 

3

1.0

3.9

28.8

94.9

 

Average

1.0

3.8

28.1

87.3

 

SD

0.0

0.1

2.2

13.7

64.4

1

1.0

3.4

26.9

96.5

 

2

1.0

3.6

21.7

41.9

 

3

1.0

3.2

27.2

88.5

 

Average

1.0

3.4

25.2

75.6

 

SD

0.0

0.2

3.1

29.5

160

1

1.0

3.4

27.9

81.1

 

2

1.0

2.6

26.6

78.0

 

3

1.0

2.9

24.3

83.4

 

Average

1.0

3.0

26.2

80.9

 

SD

0.0

0.4

1.8

2.7

400

1

1.0

2.1

15.0

33.8

 

2

1.0

1.9

13.9

28.3

 

3

1.0

1.8

12.5

35.2

 

Average

1.0

2.0

13.8

31.4

 

SD

0.0

0.1

1.3

3.6

1000

1

1.0

1.3

2.6

3.8

 

2

1.0

1.2

3.4

3.6

 

3

1.0

1.3

3.3

3.8

 

Average

1.0

1.3

3.1

3.7

 

 

0.0

0.1

0.4

0.1

 

Validity criteria fulfilled:
yes
Conclusions:
The 72 -hour EC50 and NOEC for Selenastrum capricornutum and based on growth rate was 345 mg/L and 160 mg/L, respectively.
Executive summary:

A 72 -hour growth inhibition study with 2-hydroxyethyl methacrylate to Selenastrum capricornutum was conducted under static conditions with 3 replicates inoculated at 10,000 cells/mL per test concentration exposed to nominal test concentrations of 0 (control), 25.6, 64.0, 160, 400, and 1000 mg/L. Water samples were measured for analytical verification of test concentrations 0 and 72 hours of exposure and the resulting time-weighted mean measured concentrations were non-detectable (control), 24.4, 61.3, 153, 401, and 1020 mg/L. The 72 -hour EC50 and NOEC based on growth rate was 345 mg/L and 160 mg/L, respectively.

Description of key information

A freshwater algal toxicity test with Selenastrum capricornutum exposed to 2-hydroxyethyl methacrylate and conducted under GLPs and following OECD TG 201 resulted in a 72-hour growth rate EC50 (ErC50) and NOEC of 345 and 160 mg/L, respectively.

Key value for chemical safety assessment

EC50 for freshwater algae:
345 mg/L
EC10 or NOEC for freshwater algae:
160 mg/L

Additional information

One freshwater algal study with selenastrum capricornutum was available for 2-hydroxyethyl methacrylate and considered reliable for assessment of this endpoint. The study was conducted with selenastrum capricornutum and found to be of good quality and assigned a Klimisch score of one. The study was conducted for 72-hours, under static conditions, following OECD Test Guideline 201, and under GLPs. The study concluded that the 72-hour growth rate EC50 (ErC50) and NOEC was 345 and 160 mg/L, respectively and considered the key parameters for this endpoint.