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Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

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Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP compliant, guideline study, available as an unpublished report, no restrictions, fully adequate for assessment

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2012
Report date:
2012

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
GLP compliance:
yes (incl. QA statement)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): Diamminedichloropalladium (II)
- Molecular formula (if other than submission substance): Cl2H6N2Pd
- Molecular weight (if other than submission substance): 211.39 g/mole
- Physical state: yellow powder
- Analytical purity: >99.5%
- Composition of test material, percentage of components: 50.33% Palladium
- Lot/batch No.: 11011
- Expiration date of the lot/batch: 31 October 2012
- Storage condition of test material: Room temperature (15 - 30°C)


Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Samples were taken from the test media at test start and after 72 hours. At test start a sample of fresh control media and freshly prepared test media of each treatment were taken prior to distributing the test media to the test containers. After 72 hours samples of the replicate vessels from each treatment were pooled prior to analysis. Samples were taken and filtered (0.2µm). Solutions were acidified with nitric acid (target concentration 3% HNO3) and stored at 4°C until analysis.

Test solutions

Vehicle:
no
Details on test solutions:
A stock solution of 19.87 mg diamminedichloropalladium/L was prepared by dissolving adequate amounts of test item in sterile growth medium in a sterile glass bottle and stirring for one hour. The stock solution was diluted with 10-fold concentrated growth medium and ultrapure water under sterile conditions to obtain the required test concentrations.

Test organisms

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
TEST ORGANISM
- Common name: freshwater alga
- Strain: SAG 61.81
- Source (laboratory, culture collection): SAG, Culture Collection of Algae at Pflanzenphysiologisches Institut of the University of Göttingen, Albrecht von Haller Institut, Untere Klarspüle 2, D-37073 Göttingen.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
72 h

Test conditions

Hardness:
Not reported
Test temperature:
21 - 22 °C
pH:
At test start: 7.88 - 8.09
At end of test: 7.29 - 8.12
Dissolved oxygen:
Not reported
Salinity:
Not relevant
Nominal and measured concentrations:
Nominal concentrations: Control, 1.24, 2.48, 4.97, 9.94 and 19.87 g DDP/L
corresponding to Control, 0.625, 1.25, 2.5, 5.0 and 10.0 µg palladium/L,
Mean measured (geometric mean) concentrations: Control, 0.140, 0.286, 0.765, 1.33 and 3.56 µg palladium/L,
corresponding to Control, 0.278, 0.569, 1.52,2.65 and 7.08 µg DDP/L

Details on test conditions:
TEST SYSTEM
- Test vessel: Conical flask
- Type: covered with air-permeable silicon sponge caps
- Material, size, headspace, fill volume: Glass, 250 mL containing 100 mL test medium
- Initial cells density: 10,000 cells/mL
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 8

GROWTH MEDIUM
- Standard medium used: yes

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: sterile ultrapure water

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: No
- Light intensity and quality: OSRAM "day light" 4440 - 8880 Lux (60 - 120 µE/m2/s)
- Shaken at a rate of 100 rpm

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: electronic particle counter

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2

- Range finding study: Yes
- Test concentrations: Not reported
Reference substance (positive control):
yes
Remarks:
3,5-dichlorophenol

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
4.03 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Remarks:
Diamminedichloropalladium
Basis for effect:
other: yield
Remarks on result:
other: 95% CL 3.58 - 4.85
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
2.84 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Remarks:
Diamminedichloropalladium
Basis for effect:
other: yield
Remarks on result:
other: 95% CL 2.50 - 3.16
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
2.64 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Remarks:
Diamminedichloropalladium
Basis for effect:
other: yield
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
5.88 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Remarks:
Diamminedichloropalladium
Basis for effect:
growth rate
Remarks on result:
other: 95% CL 5.27 - 6.22
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
3.74 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Remarks:
Diamminedichloropalladium
Basis for effect:
growth rate
Remarks on result:
other: 95% CL 2.56 - 4.45
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
2.64 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Remarks:
Diamminedichloropalladium
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
2.03 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
Palladium
Basis for effect:
other: yield
Remarks on result:
other: 95% CL 1.80 - 2.44
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
1.43 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
Palladium
Basis for effect:
other: yield
Remarks on result:
other: 95% CL 1.26 - 1.59
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
1.33 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
Palladium
Basis for effect:
other: yield
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
2.96 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
Palladium
Basis for effect:
growth rate
Remarks on result:
other: 95% CL 2.65 - 3.13
Key result
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
1.88 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
Palladium
Basis for effect:
growth rate
Remarks on result:
other: 95% CL 1.29 - 2.24
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
1.33 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
Palladium
Basis for effect:
growth rate
Results with reference substance (positive control):
The sensitivity of the test organism is routinely checked using 3,5-dichlorophenol. The nominal ErC50 value of 2.91 mg/L (95% confidence limits 2.35 - 3.63 mg/L) is in good agreement with the results of an international ring test with ErC50 of 3.38 ± 1.30 mg/L.
Reported statistics and error estimates:
Test results were statistically analysed to determine EC values together with 95 % confidence intervals using Probit-analysis assuming log-normal distribution of the values. Individual replicate responses were used for the regression analysis.
The NOEC and LOEC values for growth rate were determined by the Mann-Whitney U-test with Bonferroni correction and for yield by the Williams Multiple Sequential t-test.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The 72-hour ErC50 and ErC10 for growth rate were 5.88 and 3.74 μg test item/L, respectively based on mean measured concentrations of diamminedichloropalladium. For yield the EYC50 and EYC10 values were 4.03 and 2.84 μg /L. NOEC for both growth rate and yield were 2.64 μg test item/L.

Based on the mean measured concentrations of dissolved palladium, the EC50 values for growth rate and yield were 2.96 and 2.03 μg Pd/L. The EC10 values were 1.88 and 1.43 μg Pd/L for growth rate and yield, respectively. The NOEC values for both growth rate and yield were calculated to be 1.33 μg Pd/L.
Executive summary:

A GLP compliant, OECD guideline study to assess algal growth was carried out (Fraunhofer 2012). It is considered to be suitable for use as the key study for this endpoint.