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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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Meets the criteria for classification as Reliable without restriction according to Klimisch et al (1997)

Data source

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

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
The concentration ofvthe test substance in th test solutions was measured at 0 and 48 hours.

Test solutions

Vehicle:
no
Details on test solutions:
Identity and concentration of auxiliary solvent for dispersal: It was not possible to make observations at 24 hours due to
the intensity of the colour in the nominal 120mg/l test
solution.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
The test species was the freshwater crustacean, Daphnia magna, obtained from continuous laboratory cultures.

The stock cultures of Daphnia were maintained in a reconstituted water medium, identical to the test dilution water, at a temperature of 20 ± 1°C. The cultures were maintained in 2 l glass vessels with a working volume of 1.5 l. A photoperiod of 16 hours light:8 hours dark, with 20 minute dusk and dawn transition periods was provided.

The Daphnia cultures were fed a defined diet of algae Chlorella vulgaris, strain CCAP 211/12 and a commercially available fish food. Culture conditions were such that the Daphnia reproduction was by diploid parthenogenesis. Daphnia <24 hours old (first instar), obtained from a single culture vessel, were used for testing. The parent animals were 19 ± 1 days old and had been maintained with a twice weekly renewal of reconstituted water medium. The test organisms and the culture from which they were obtained showed no evidence of disease before the test period.

Study design

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

Test conditions

Hardness:
The thermometer readings at 0, 24 and 48 hours were 19.6, 19.9 and 19.8°C. The continuous temperature recorded automatically over the 48 hours remained within 20 ± 1°C.
Test temperature:
Temperature values were determined daily using a mercury-in-glass thermometer. Hourly measurements were also recorded automatically in the additional dilution water control test vessel using a calibrated electronic recording system. The thermometer readings at 0, 24 and 48 hours were 19.6, 19.9 and 19.8°C. The continuous temperature recorded automatically over the 48 hours remained within 20 ± 1°C.
pH:
pH values were measured at 0 hours and 48 hours and ranged from 7.8 to 8.1
Dissolved oxygen:
Dissolved oxygen concentrations ranged from 9.4 to 9.8 mg/l. At no time during the course of the study was dissolved oxygen concentration in any of the test vessels less than 60% of the air-saturation value (9.1 mg/l) as given in the National Institute of Oceanography of Great Britain and UNESCO (1973). International Oceanographic Tables, 2.
Salinity:
Not applicable - freshwater test
Nominal and measured concentrations:
The ocncentration of the test substance in the test solutions was measured at 0 and 48 hours using high performance liquid chromatography. The overall mean measured concentration was 100% of the nominal values. The percentage loss in the measured concentration over the test period was <1%.

The nominal concentrations were used for the calculation and reporting of results.
Details on test conditions:
Borosilicate glass beakers of 250 ml nominal capacity were used as test vessels, with four replicates per test concentration. Each vessel contained 200 ml of test solution providing a depth of approximately 60 mm. The beakers were covered with loose fitting glass lids. The positions of the treatments were randomly allocated within the test area.

The test was initiated by the addition of five randomly selected Daphnia, in <2.0 ml of dilution water, to each test vessel in sequence across the treatments within 5 minutes of the test solution preparation. Each treatment contained a total of 20 Daphnia. The loading of the Daphnia in each test vessel was 25 Daphnia per litre. The nominal test solution temperature was 20 ± 1°C, maintained by control of the room temperature. A photoperiod of 16 hours light:8 hours dark, with 20 minute dusk and dawn transition periods, was provided. The test solutions were not aerated and the Daphnia were not fed during the course of the study.

An assessment of the response of the Daphnia was made 48 hours after the commencement of the test. Due to the intensity of colour in the nominal 120 mg/l test solution it was not possible to make observations at 24 hours. Each Daphnia was viewed by eye and was defined as affected if showing no whole body movement, relative to the water, within a period of 15 seconds even if movement of individual appendages was visible. Daphnia so affected were termed immobile. Any overt symptoms of toxicity were also recorded.
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 120 mg/L
Duration:
48 h
Dose descriptor:
EC100
Effect conc.:
> 120 mg/L
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
120 mg/L

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Under the conditions of the test the test susbtance was considered non toxic to Daphnia magna at up to concentrations of 120 mg/l.