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Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
72 hours, 27 to 30 June 1995
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline and GLP-compliant study.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1995
Report Date:
1995

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method C.3 (Algal Inhibition test)
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): BEPD
- Physical state: colourless solid
- Analytical purity: 99.5%
- Lot/batch No.: HRC accession number 20.4.95/1
- Expiration date of the lot/batch: 31 December 1995.
- Storage condition of test material: in darkness at room temperature (ca. 20 degrees C).
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Samples were taken at 0 hours (fresh media) and 72 hours (expired media).

Test solutions

Vehicle:
no
Details on test solutions:
The test material was dispersed directly in sterile nutrient medium with the aid of unltrasonic disruption for 30 minutes.

Test organisms

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
- Strain number: CCAP 278/4
- Source: Culture Centre of Algae & Protozoa c/o Freshwater Biological Association, Cumbria, UK.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
72 h
Post exposure observation period:
Not applicable

Test conditions

Test temperature:
23 °C
pH:
7.3 - 8.1
Dissolved oxygen:
Not applicable
Salinity:
Not applicable
Nominal and measured concentrations:
Nominal: 2.2, 4.6, 10, 22, 46 and 100 mg/L
Measured: 2.2, 4.6, 9.8, 21, 45 and 100 mg/L

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
94 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
biomass
Remarks:
(area under the growth curve, EbC50)
Remarks on result:
other: 95% CL: 83 - 106 mg BEPD/L
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
45 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
act. ingr.
Basis for effect:
growth rate
Results with reference substance (positive control):
Not applicable
Reported statistics and error estimates:
Williams' test (1971, 1972) was used to compare the percentage inhibition in each treated group with the baseline (control) values. Bartlett's test for homogeneity of variance (1937) was also applied.

Any other information on results incl. tables

Results of the definitive test are compiled below:

Nominal BEPD concentration (mg/L)

Mean BEPD concentration (mg/L)

Mean cell counts (cells x 10000/ml)

0 hours

72 hours

Mean

Mean as % of nominal

0 hours

24 hours

48 hours

72 hours

Control

ND

ND

-

-

0.99

3.7

12

59

2.2

2.121

2.230

2.2

99

0.99

3.2

12

57

4.6

4.450

4.800

4.6

101

1.0

3.8

31

65

10

9.400

10.10

9.8

98

0.97

3.8

12

59

22

20.08

21.22

21

94

1.0

3.8

13

60

46

43.07

47.09

45

98

0.99

3.6

11

53

100

98.13

103.6

100

101

0.99

3.0

6.2

25

ND: None detected

E: Expired media

Nominal BEPD concentration (mg/L)

Mean measured concentration mg BEPD/L

Area under curve at 72 h

% Inhibition*

Growth rate (0 - 72 h)

% Inhibition*

Control

Control

1018

0

0.057

0

2.2

2.2

981

4

0.056

1

4.6

4.6

1137

<12>

0.058

<2>

10

9.8

1040

<2>

0.057

<1>

22

21

1062

<4>

0.057

0

46

45

936

8

0.055

3

100

100

460

55

0.045

21

* Percentage inhibition values calculated using non-rounded data

< > Increase in algal growth

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The 72-hour ErC50 (growth rate), EbC50 (integrated biomass) for S. capricornutum exposed to BEPD under static conditions were >100 and 94 mg BEPD/L, respectively.
Executive summary:

S. capricornutum was exposed to BEPD at nominal concentrations of 2.2, 4.6, 10, 22, 46 and 100 mg/L in a static 72 -hour toxicity test carried out according to OECD 201 guidelines. The test design included an untreated control comprising untreated algal growth medium only. Concentrations of BEPD were verified analytically at test initiation and termination and measured concentrations were 91 - 98% of nominal. The 72 -hour ErC50 and EbC50 endpoints determined were >100 and 94 mg BEPD/L, respectively. The corresponding 72 -hour NOEC based on inhibition of specific growth rate, determined using Williams' test analysis, was 45 mg BEPD/L.