Magnesium bis(dinonylnaphthalenesulphonate)

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.23 µg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

2.3 µg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.023 µg/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:

PNEC sediment (freshwater)

PNEC value:

1.83 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.183 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:

0.36 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

6.3 mg/kg food

Assessment factor:

300

Additional information

Short-term toxicity data for aquatic endpoints are available on the analogues of the test substance. The PNEC is based on the water solubility, because no effects were observed in any of the tests at concentrations below the water solubility. An assessment factor (AF) of 1000 is applied to derive the PNECwater. Thus, PNECwater is 0.23 µg/L. For lacking the toxicity data for marine water organisms an AF of 10000 is applied to derive PNECsaltwater. Thus, the PNECsaltwater 0.023 µg/L An AF of 100 is applied to derive PNECaqua (intermittent releases), thus PNECaqua (intermittent release) is 2.3 µg/L.

The NOECmicro-organism was 100 mg/L based on the active sludge respiration inhibition test. An AF of 10 is applied. Thus, the PNECstp is 10 mg/L.

As no data on sediment dwelling organisms and terrestrial organisms is available, EPM is applied to derive PNECsed, PNECmarine-sed and PNECsoil. Based on the available Koc, water solubility, molecular weight and vapour pressure, the PNECsed, PNECmarine-sed and PNECsoil are 1.8, 0.18 and 0.36 mg/kg dw respectively according to guidance on information requirements and chemical safety assessment chapter R.10.: characterisation of dose[concentration]-response for environment.

PNEC oral is derived based on the available repeated dose toxicity data on DNNSA ( di C8-C10, branched, C9 rich, alkylnaphthalene sulphonic acid), CONVrat of 20 kg bw*d/kg food is applied for and AF oral of 300 is applied. Thus, PNECoral is 6.3 mg/kg food.

The VP of the substance is very low (0.00000001 Pa at 20 degree C), thus the very limited hazard for air is expected.

Read-across from a close structural analogue DNNSA was applied (see document on read-across section 13).

Conclusion on classification

In none of the acute aquatic toxicity tests performed on fish, daphnia and algae, an LC50 or EC50 could be achieved within limits of solubility. Thus, the L(E)C50 on all three trophic levels is considered above water solubility and no classification for acute aquatic toxicity is derived according to CLP (Regulation EC No 1272/2008) or DSD (Directive 67/548/EEC). Although the log of n-octanol/water partitioning coefficient was 6.2, the molecular size is > 18 A, thus hampering passage of the biomembranes.A valid BCF QSAR showed that the BCF is expected to be < 2000. Therefore the substance is not expected to bioaccumulate. Thus, the substance is also not classifiable for chronic aquatic toxicity according to CLP or DSD.