Potassium sulfate

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.68 mg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

6.8 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.068 mg/L

Assessment factor:

10 000

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

10 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

insufficient hazard data available (further information necessary)

Sediment (marine water)

Hazard assessment conclusion:

insufficient hazard data available (further information necessary)

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

insufficient hazard data available (further information necessary)

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

PNEC aqua (freshwater)

For the 3 trophic levels (fish, invertebrates (Daphnia) and algae), several studies on the short-term toxicity are available. Therefore the lowest L(E)C50 observed from all conducted studies, a 96h-LC50 of 680 mg/L for Pimephales promelasis used for the derivation of the PNEC. An AF of 1000 is used in accordance with the “Guidance on information requirements and chemical safety assessment, Chapter R.10”.

PNEC aqua (freshwater): 0.68 mg/L

 

PNEC aqua (marine water)

For the 3 trophic levels (fish, invertebrates (Daphnia) and algae), several studies on the short-term toxicity are available. No studies with species in marine water are available, therefore the lowest L(E)C50 observed from all fresh water conducted studies, a 96h-LC50 of 680 mg/L for Pimephales promelasis used for the derivation of the PNEC. An AF of 10000 is then used in accordance with the “Guidance on information requirements and chemical safety assessment, Chapter R.10”.

PNEC aqua (marine water): 0.068 mg/L

PNEC (intermittent releases)

For the 3 trophic levels (fish, invertebrates (Daphnia) and algae), several studies on the short-term toxicity are available. Therefore the lowest L(E)C50 observed from all conducted studies, a 96h-LC50 of 680 mg/L for Pimephales promelasis used for the derivation of the PNEC. An AF of 100 is used in accordance with the “Guidance on information requirements and chemical safety assessment, Chapter R.10”.

PNEC (intermittent releases): 6.8 mg/L

 

PNEC STP

The substance is inorganic, therefore no ready biodegradability test is available. In addition, no study on toxicity to micro-organisms is available. However, In view of the use of the substances (fertilizer) and the available data on the other trophic levels (fish, invertebrates and algae) with the different inorganic sulphates, no toxicity is expected from potassium sulphate. In addition, sulphates are known to be important for some microorganisms, e.g. some anaerobic microorganisms use sulphates as electron acceptors. Therefore, it is concluded that the EC50 >100 mg/L and NOEC is 100 mg/L for inorganic sulphates and thus no study need to be conducted. An AF of 10 is used in accordance with the “Guidance on information requirements and chemical safety assessment, Chapter R.10”.

PNEC STP: 10 mg/L

 

Conclusion on classification

Based on the results of the available studies, both with potassium sulphate itself as well as with other inorganic sulphates, the substance does not need to be classified according to Directive 67/548/EC or the CLP Directive with regard to the environment.

As potassium sulphate is an inorganic substance, no PBT or vPvB assessment has to be performed in accordance with Annex XIII of REACH.