Palladium (II) di(4-oxopent-2-en-2-oate)

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

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: Good-quality, well-documented study in accordance with OECD guideline. Study was conducted according to GLP and has a reliability score of 1 (reliable without restriction).

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Remarks:

WCA-002/4-20/G

Analytical monitoring:

yes

Details on sampling:

Sampling at test start before distribution to replicates and sampling of aged test solution by pooling replicate concentration samples.

Vehicle:

no

Details on test solutions:

- Stock concentration: 10 mg/L
- Stock preparation method: stirred slowly for 48h at ca. 20C, followed by 1h resting period to separate suspended particles from aqueous phase before use

Test organisms (species):

Daphnia magna

Details on test organisms:

- Strain: Clone V
- Source: Fraunhofer IME
- Age at study initiation (mean and range, SD): 4-24hr
- Feeding during test: no

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

70-120 mg/L as CaCO3 - below recommended range; historical conditions at laboratory indicate that this range is acceptable for the Daphnia magna strain used at the IME

Test temperature:

20.4-20.6 degrees Celsius

pH:

8.2-8.4

Dissolved oxygen:

8.4-8.7 mg/L

Nominal and measured concentrations:

Nominal concentration (mg/L): 0.20, 0.43, 0.94, 2.07, 4.55, 10
Pd concentration (mg Pd/L): 0.07, 0.15, 0.33, 0.72, 1.59, 3.50

Details on test conditions:

- Test vessel: glass beaker
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 50mL
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates):4
- Control: dilution water
- Light intensity:9.9-10.0 uE/m2/s
- Light/dark cycle:16/8

All OECD guidelines on water quality were met, except for water hardness.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.217 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

morphology

Remarks on result:

other: 95% CL: 0.177 - 0.269 mg/L

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

0.126 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% CL: 0.081 - 0.0158 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

<= 0.105 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

<= 0.225 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

No significant signs of distress or disease were observed.

Results with reference substance (positive control):

24h EC50 immobilisation with K2Cr2O7: 1.19 mg/L
95% CL: 1.08-1.36 mg/L

Reported statistics and error estimates:

95% confidence intervals calculated by Probit-analysis, assuming log-normal distribution of the values.
Statistical calculations performed with ToxRat.

	Mortality
NOEC	0.105
LOEC	0.225
EC10 (95% CL)	0.126 (0.081 -0.158)
EC20 (95% CL)	0.152 (0.109 -0.185)
EC50 (95% CL)	0.217 (0.177 -0.269)

Validity criteria fulfilled:

yes

Conclusions:

Palladium di(4-oxopent-2-en-2-oate) impaired Daphnia magna under the chosen test conditions. The EC50 was found to be 0.217 (95 % CL: 0.177 – 0.269) mg/L. The NOEC was found to be 0.105 mg/L.

Executive summary:

The influence of palladium di(4-oxopent-2-en-2-oate) on the mortality of the species Daphnia magna was investigated according to OECD guideline 202 and EC method C.2. The daphnids were placed in water containing the test item in a nominal concentration range of 0.2 to 10 mg test item per litre, corresponding to a measured concentration range of 0.07 to 3.50 mg Pd per litre. The test was conducted under static conditions for 48 h. No significantly increased mortality (NOEC) up to a concentration of 0.105 mg palladium di(4-oxopent-2-en-2-oate) per litre was detected when compared to the control daphnids. The EC50 for the tested species was found to be 0.217 (95 % CL: 0.177 – 0.269) mg palladium di(4-oxopent-2-en-2-oate) per litre. No other significant signs of disease or distress were observed in the test specimen.

The study was conducted in accordance with GLP and all validation criteria were met. This study has been given a reliability rating of 1 as being well-documented and adhering to guideline procedures.

Description of key information

The EC50 value was determined to be 0.217 mg test item/L (0.076 mg Pd L-1).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.217 mg/L

Additional information

An acute Daphnia magna study is available for palladium di(4-oxopent-2-en-2-oate) (Simon 2014). The study followed OECD guideline 202, with six test concentrations. Test solutions were analysed and were within 50 and 61% of nominal at in new and aged solutions. As test concentrations were stable but less than 80% of nominal, results were based on initial measured concentrations. The EC50 value was determined to be 0.217 mg test item/L (0.076 mg Pd L^-1).