Registration Dossier

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:
30 August 1993 - 02 September 1993
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study was performed to an OECD test guideline and a statement to GLP compliance is included in the study report.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1993
Report Date:
1993

Materials and methods

Test guideline
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): dimethylolpropionic acid or 2,2-bis(hydroxymethyl)propionic acid (reported as Bis-MPA in this summary)
- Lot/batch No.: 63004-14
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
No applicable

Sampling and analysis

Analytical monitoring:
not specified
Details on sampling:
Not applicable

Test solutions

Vehicle:
no

Test organisms

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
- Source (laboratory, culture collection): Inoculum taken from Toxicon's own culture, which originated from the Swedish Environmental Protection Agency, Stockholm, Sweden.
-clone quoted as SEPA-clone

Study design

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

Test conditions

Hardness:
Not applicable
Test temperature:
23.5 (start of exposure) to 25.0 ºC (after 72 hours exposure).
pH:
pH in the nominal 1000 mg/L treatment was 3.5, the pH was therefore adjusted to 8.3 ± 0.2, adjusted with 1M NaOH. The initial pH in the control was 8.1, in the 100 mg/L treatment 8.4 and the 1000 mg/L 8.3, at the end of the 72 hour exposure period the pH values were 8.8 (control), 9.1 (100 mg/L) and 7.9 mg/L (1000 mg/L.)
Dissolved oxygen:
Not applicable
Salinity:
Not applicable
Nominal and measured concentrations:
0, 100, and 1000 mg/L.
Details on test conditions:
TEST SYSTEM
- Test vessels: 250 mL glass E-bottles with 100 mL solution
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 5

GROWTH MEDIUM
- Standard medium used: not specified
- Detailed composition if non-standard medium was used: refer to further details on methods.


OTHER TEST CONDITIONS
- Adjustment of pH: because of low pH, test solutions were adjusted with 1M NaOH solution to 8.3 ± 0.2.
- Photoperiod: continuous illumination
- Light intensity and quality:100 µE/m2/s


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : sampling at 0, 24, 48, and 72 hours
- Determination of cell concentrations: Fluorescence
- Chlorophyll measurement: Yes

Reference substance (positive control):
no

Results and discussion

Effect concentrations
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
750 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Details on results:
EC50 was graphically determined to be 750 mg/L.
Results with reference substance (positive control):
Not applicable
Reported statistics and error estimates:
Graphical estimation of the EC50
Growth rate calculated as per the OECD guidelines

Any other information on results incl. tables

Algal growth rates and percentage growth rate inhibition relative to the control.

 

Control

100 mg/L

1000 mg/L

 Growth rate, µ

1.83

1.84

0.58

Percent inhibition

0

 -0.7

68.4

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
A 72 hour algal growth inhibition study, test species, Selenastrum capricornutum, was performed to determine the toxic effects of the test substance Bis-MPA . The test was conducted according to OECD test guideline 201, and performed to GLP. The 72 hour EC50 value, based on growth rate, was calculated as 750 mg/L (based on nominal exposure concentrations).
Executive summary:

A 72 hour algal growth inhibition study, test species, Selenastrum capricornutum, was performed to determine the toxic effects of the test substance Bis-MPA. The test was conducted according to OECD test guideline 201, and performed to GLP. The 72 hour EC50 value, based on growth rate, was calculated as 750 mg/L (based on nominal exposure concentrations).