Lithium neodecanoate

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.495 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.94 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.049 mg/L

Assessment factor:

100

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

35.94 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

191.7 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

19.2 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

2 577 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

0.017 g/kg food

Assessment factor:

90

Additional information

Metal carboxylates are substances consisting of a metal cation and a carboxylic acid anion. Based on the solubility of lithium neodecanoate in water, dissociation of lithium neodecanoate resulting in lithium cations and neodecanoate anions may be assumed under environmental conditions. The respective dissociation is reversible, and the ratio of the salt /dissociated ions is dependent on the metal-ligand dissociation constant of the salt, the composition of the solution and its pH.

Ionic lithium (Li+) at relevant pH conditions (pH 6 - 10) of aquatic and terrestrial environments transforms to lithium-oxide and -hydroxide complexes. Therefore, lithium ions are expected to have a lower mobility and bioavailability under most environmental conditions whereas neodecanoate is rather mobile.

Thus, it may reasonably be assumed that the respective behaviour of lithium cations and neodecanoate anions in the environment determine the fate of lithium neodecanoate upon dissolution with regard to (bio)degradation, bioaccumulation, partitioning resulting in a different relative distribution in environmental compartments (water, air, sediment and soil) and subsequently its ecotoxicological potential.

Thus, in the assessment of environmental toxicity and pathways of lithium neodecanoate, read-across to the assessment entities lithium ions and neodecanoate is applied since the individual ions of lithium neodecanoate salts determine its toxicity. Since lithium ions and neodecanoate ions behave differently in the environment, regarding their fate and toxicity, a separate assessment of each assessment entity is performed. Please refer to the data as submitted for each individual assessment entity. For a documentation and justification of that approach, please refer to the separate document attached to section 13, namely Read Across Assessment Report for lithium neodecanoate.

Conclusion on classification

Acute (short-term) toxicity:

EC/LC50 values of 3 trophic levels (algae, invertebrates and fish) for lithium cations and neodecanoate anions are above the classification cut-off value for acute (short-term) aquatic hazard category 1 of 1 mg/L. Accordingly, EC/LC50 values of 3 trophic levels (algae, invertebrates and fish) for lithium neodecanoate are well above the classification cut-off value for acute (short-term) aquatic hazard category 1 of 1 mg/L. In accordance with Regulation (EC) No 1272/2008, Table 4.1.0 (a), classification for acute (short-term) aquatic hazard is not required for lithium neodecanoate.

 

Chronic (long-term) toxicity:

Long-term EC10/NOEC values of 3 trophic levels (algae, invertebrates and fish) for lithium and neodecanoate are above the classification cut-off value for chronic (long-term) aquatic hazard of 1 mg/L. Accordingly, EC10/NOEC values values of 3 trophic levels (algae, invertebrates and fish) for lithium neodecanoate are well above the classification cut-off value for long-term aquatic hazard of 1 mg/L. In accordance with Regulation (EC) No 1272/2008, Table 4.1.0 (b), classification for long--term aquatic hazard is not required for lithium neodecanoate.

In sum, based on read-across of toxicity data available for lithium and neodecanoate, lithium neodecanoate does not meet acute or long-term aquatic hazard criteria of Regulation (EC) No 1272/2008.