Registration Dossier

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:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Qualifier:
according to
Guideline:
EU Method C.3 (Algal Inhibition test)
Deviations:
not specified
GLP compliance:
yes
Analytical monitoring:
no
Vehicle:
no
Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
Origin: Pflanzenphysiologisches Institut der Universität Göttingen
Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h
pH:
8.1 - 10.3
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
>= 40 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 40 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate

It was reported that no inhibition occured in the range of the water solubility.

The pH-value increased in the control 2.0 and at the concentration of 40 mg/l 2.2 units.

Conclusions:
No growth inhibition of MBTS on Desmodesmus subspicatus was observed up to its water solubility (<40mg/l).
Executive summary:

No growth inhibition of MBTS on Desmodesmus subspicatus was observed up to its water solubility (<40mg/l) according to EU Method C.3 (Bayer AG, 1992).

Description of key information

No growth inhibition of MBTS on Desmodesmus subspicatus was observed up to its

water solubility (<40mg/l) according to EU Method C.3 (Bayer AG, 1992).

Key value for chemical safety assessment

Additional information

The absolute values of chlorophyll and/or cell numbers were not reported for control experiment in Monsanto study from 1979 and hence no exponential growth can be concluded from this study. Therefore the information provided in this study is not sufficient for assessment. Although this study was used in EU-risk assessment, this study is assigned to be a reliability of 4 in the up-to-date assessment and will not be used in the risk assessment under REACH.