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Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
December, 2004
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study performed according to OECD guideline, but with nominal concentrations and without GLP compliance.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2004
Report Date:
2004

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
Qualifier:
according to
Guideline:
ISO 6341 15 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent
Test material form:
other: Crystallized solid mass at room temperature
Details on test material:
- Name of test material (as cited in study report): ODEB
- For more details, see below the "confidential details on test material"

Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
Not relevant

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
Due to the very low solubility in water, according to its Rhodia's SDS, the test item was submitted to a "water soluble fraction" approach, by placing it in four different flasks at concentrations of 1, 10, 100A and 100B mg/L.
- Method: Water soluble fraction
- Controls: no data
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no observed

Preparation of the test solution:
The day before the test, solutions of 100mg/L, 10mg/L and 1mg/L of the test substance were prepared in the test medium. The solutions were continuously stirred for 24 hours at approximately 25ºC. The solutions were brought to 20ºC before starting the test.
On the day of the test, the soluble fractions of each one of the four solutions were separated by decantation, during 2 hours. After that, they were introduced into the test bottles.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: Daphnia magna
- Strain: Straus, 1820 (Cladocera, Crustacea)
- Source: IAP (Instituto Ambiental do Parana)
- Age at study initiation (mean and range, SD): <24 hours
- Feeding during test : no
- Food type: unicellular green algae Scenedesmus subspicatus
- Amount: no data
- Frequency: once a day

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h
Post exposure observation period:
No

Test conditions

Hardness:
242 mg/L (as CaCO3)
Test temperature:
19.3 - 20.4°C
pH:
7.56 (mean of initial exposure measures) to 7.62 (mean of final exposure measures)
Dissolved oxygen:
7.48 (initial) to 7.26 (final)
Salinity:
No data
Nominal and measured concentrations:
Nominal concentrations only : Control - 1 - 10 and 100 (duplicate) mg/L
Reference substance (positive control):
yes
Remarks:
Potassium Dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 10 - < 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
- Behavioural abnormalities: no data
- Mortality of control: no mortality or immobility observed
- Other adverse effects control: no observed
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: concentration nominal only
Results with reference substance (positive control):
CE50 -24h Potassium Dichromate = 0.91 mg/L
95% confidence limits [0.86 - 0.97] mg/L

Any other information on results incl. tables

 Initial Concentration

(mg/L)

    Becher 1 (nb of mobile organisms)     Becher 2 (nb of mobile organisms)
24h  48h   24h 48h 
 100A  5 2
 100B  7
 10  10 10  10  10 
 1  10 10  10  10 
 Control  10 10  10  10 

Initial Concentration

(mg/L)

  Immobile organisms 24h     Immobile organisms 48h
Total number Percentage Total number Percentage
 100A  11 55 17  85 
 100B  8 40  18  90 
 10  0
 1  0
 Control 0

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Ortho-Diethoxy Benzene has an EC50 between 10 and 100 mg/L, according to study performed with OECD Guideline 202.
Executive summary:

The 48 hours acute toxicity of Ortho-Diethoxy Benzenz to Daphnia magna was studied under static conditions.  Daphnids were exposed to control and test chemical at nominal concentration from 1 to 100 mg/L (purity of 99.65%) for 48 hours (pH adjusted).The 48 hours EC50was between 10 and 100 mg/L.

 Based on the results of this study, the test item was classified as harmful to Daphnia magna in accordance with the EC classification criteria.

Results Synopsis

Test Type: static

48h - EC50: between 10 and 100 mg/L

Endpoint(s) effected: mobility