Palladium

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP status not known, guideline experimental study minor restrictions in design and/or reporting but otherwise adequate for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Series on Testing and Assessment No. 29 (23-Jul-2001): Guidance document on transformation/dissolution of metals and metal compounds in aqueous media

Qualifier:

according to guideline

Guideline:

other: UN Transformation/Dissolution Protocol (T/DP) for Metals and Sparingly Soluble Metal Compounds.

GLP compliance:

not specified

Type of method:

other: Transformation/dissolution

Water solubility:

0 µg/L

Temp.:

22.3 °C

pH:

5.92 - 6.13

Remarks on result:

other: pH 6 24-hr scoping study. Test Duration; 24 Hours, Pd Loading; 100 mg/L, σ = 0.00, Temperature Range; 22.1 - 22.5 ºC, DO; 5.9 - 8.3 mg/L. Result

Water solubility:

0 µg/L

Temp.:

21.9 °C

pH:

>= 8.5 - <= 8.65

Remarks on result:

other: pH 8.5 24-hr scoping study. Test Duration; 24 Hours, Pd Loading; 100 mg/L, σ = 0.00, Temperature Range; 21.6 - 22.3ºC, DO; 6.8 - 7.5 mg/L. Result

Water solubility:

0 µg/L

Temp.:

21.5 °C

pH:

>= 5.89 - <= 6.43

Remarks on result:

other: Test Duration; 28 Days, Pd Loading; 1 mg/L, σ = 0.00, Temperature Range; 20.7 - 22.4 ºC, DO; 7.9 - 10.4 mg/L

Water solubility:

0 µg/L

Temp.:

21.4 °C

pH:

5.83 - 6.38

Remarks on result:

other: Test Duration; 7 Days, Pd Loading; 10 mg/L, σ = 0.00, Temperature Range; 20.6 - 21.7 ºC, DO; 7.7 - 9.6 mg/L

Water solubility:

0 µg/L

Temp.:

21.2 °C

pH:

5.83 - 6.29

Remarks on result:

other: Test Duration; 7 Days, Pd Loading; 100 mg/L, σ = 0.00, Temperature Range; 20.4 - 21.4 ºC, DO; 7.7 - 9.9 mg/L

Details on results:

The results for the 24 hour scoping tests at pH 6 and 8.5 reveal that Pd was within the sub-µg/L analytical detection limits, and singularly unreactive at either pH. The 28-day T/D data for the 1, 10 and 100 mg Pd/L loadings reveal that within analytical detection limits, Pd metal was unreactive, yielding net values of 0.00 µg/L at all sampling times.

Definitive 7 and 28 days T/D tests were only performed at pH 6 on the grounds that metals are generally more reactive at this pH than pH 8.5

Conclusions:

The 28-day T/D data for the 1, 10 and 100 mg Pd/L loadings reveal that within analytical detection limits, Pd metal was unreactive, yielding net values of <0.01 µg/L (LOQ) at all sampling times.

Executive summary:

This is a guideline experimental study, of unknown GLP status, there are minor restrictions in design and/or reporting but otherwise adequate for assessment as a key study for this endpoint. The 28-day T/D data for the 1, 10 and 100 mg Pd/L loadings reveal that within analytical detection limits, Pd metal was unreactive, yielding net values of <0.01 µg/L (LOQ) at all sampling times.

Description of key information

The 28-day T/D data for the 1, 10 and 100 mg Pd/L loadings reveal that within analytical detection limits, Pd metal was unreactive, yielding net values of <0.01 µg/L (LOQ) at all sampling times.

Key value for chemical safety assessment

Water solubility:

0.01 µg/L

at the temperature of:

22.3 °C

Additional information

A transformation / dissolution (TD) test is available for this substance. TD tests are a standard method for assessing the solubility of poorly soluble metal substances and provide additional data that cannot be obtained from a standard OECD 105 water solubility study.

Skeaff and Beaudoin (2011) is a guideline experimental study, of unknown GLP status, and is considered adequate for assessment as a key study for this endpoint.

A 24 -hour scoping study was conducted at pH 6 and pH 8.5, followed by a 28 -day study at pH 6 with loading rates of 1, 10 and 100 mg Pd/L. The 28-day T/D data for the 1, 10 and 100 mg Pd/L loadings reveal that within analytical detection limits, Pd metal was unreactive, yielding net values of <0.01 µg/L (LOQ) at all sampling times.