Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
10/01/2000-17/08/2000
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Study according to international guideline (OECD Guideline 201) under GLP conditions, validity criteria met.
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Analytical monitoring:
yes
Vehicle:
no
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
72 h
Remarks on exposure duration:
As 2-Ethylhexyl 4-methoxycinnamate was expected to degrade by photolysis, the test period included a pre-exposure period of 24 hours in the dark
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
> 100 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:
biomass
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
32 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Key result
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
65 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: Within range of 19 - 230 mg/L
Key result
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate

The study included sampling at all concentrations for analysis of actual exposure concentrations at the start of the test, after 24 h and 48 h and at the end of the test. Interpretation of the analytical data was not possible with respect to exposure concentrations, as most concentrations decreased below detection.

Validity criteria fulfilled:
yes
Conclusions:
The toxicity of 2-Ethylhexyl 4-methoxycinnamate towards Selenastrum capricornutum was investigated: the 72h-NOEC for growth rate was found to be 32 mg/L, the 72h-EC50 for growth rate was found to be >100 mg/L. These values are based on the nominal loadings of the WAFs tested.
Executive summary:

The toxicity of 2-Ethylhexyl 4-methoxycinnamate towards Selenastrum capricornutum was investigated according to OECD Guideline 201 under GLP conditions. The 72h-NOEC for growth rate was found to be 32 mg/L, the 72h-EC50 for growth rate was found to be >100 mg/L. These values are based on the nominal loadings of the WAFs tested, because interpretation of the analytical data of the samples collected at 24 h and 48 h and at the end of the test was not possible, as most concentrations decreased below detection. pH values in the controls increased more than the maximum of 1.5 units mentioned in OECD Guideline 201.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Test procedure conducted according to OECD guideline 201.
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
GLP compliance:
yes
Analytical monitoring:
no
Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Nominal and measured concentrations:
Nominal test concentrations (mg/L): 6.25, 12.5, 25, 50, 100, control
dilution factor 2
Details on test conditions:
Determination of mean fluorescence: 0, 24, 48, 72 h
Concentration control analysis: not performed since the detection limit of analytical method (1 mg/L) was beyond the water solubility (0.041 mg/L) of the test substance.
Key result
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Key result
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:
EC90
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate

Biomass:

EbC10 (72 h) = 74.8 mg/L

EbC50 (72 h) > 100 mg/L

EbC100 (72 h) > 100 mg/L

Description of key information

Two studies with algae result both in 72h-EC50 (growth rate) > 100 mg/L loading (OECD 201).

The 72h-NOEC is > 32 mg/L in one test and the EC10 > 100 mg/L in the other.  

Key value for chemical safety assessment

Additional information

A new study according to OECD 201 was requested by ECHA. The study is ongoing and will be submitted by the set deadline.

In both studies, the test substance was tested above its water solubility limit. Therefore, the test concentrations should be interpreted as a loading rate. No effects were observed at levels far above the water solubility at loading rates of above 32 or 100 mg/L:

Pseudokirchneriella subcapitata  (OECD 201, GLP, reliability 1) (Bogers 2000)

tested as a WAF 10 100 mg/L loading, with 24h-pre-exposure period in the dark in view of photodegradability of the test substance

  • 72h-NOEC > 32 mg/L (growth rate)
  • 72h-EC50 > 100 mg/L (growth rate)
  • Test conc. after 96 h (after 72-h of light) < 0.001 mg/L

Scenedesmus subspicatus = Desmodesmus subspicatus (OECD 201, GLP, reliability 1) (BASF 2001)

  • 72h-EC10 > 100 mg/L

  • 72h-EC50 > 100 mg/L
  • No control analysis since water solubility limit was below the detection limit of the analytical method.

The first study (Bogers 2000) is identified as the key test; it has reliability 1 and sufficient details are available.