Sulphamidic acid

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

1.8 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.48 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.18 mg/L

Assessment factor:

100

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

20 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

8.36 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.84 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:

5 mg/kg soil dw

Assessment factor:

10

Extrapolation method:

assessment factor

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

According to the available toxicity data for aquatic organisms, LC50/EC50 of the short-term toxicity tests for fish, daphnia and algae are 70.3 mg/L, 71.6 mg/L and 48 mg/L, respectively. The lowest value of such is 48 mg/L in algae and is considered as the most relevant information for deriving the PNECaquatic for intermittent release. Based on newly available long-term aquatic toxicity data (NOEC of 60 mg/L in FELS test, 19 mg/L in daphnia reproduction test and 18 mg/L in algae test) the PNECs for freshwater and marine water are derived, according to the assessment method.

As no sediment toxicity data are available and sediment toxicity is very unlikely, due to the very good solubility of the substance in water, a PNEC sediment (freshwater and marine) has been derived by applying the partitioning method in line with the technical guidance document on risk assessment.

As data for soil macroorganisms (NOEC of 290 mg/L soil ww for earthworms) and for soil microorganisms (NOEC of 100 mg/L for nitrification bacteria) as well as for plant toxicity (NOEC of 50 mg/kg soil dw) are available, Then PNECsoil could be derived by the assessment method.

Based on the result of the test for inhibition of oxygen consumption by activated sludge, the NOEC of 200 mg/L is available for deriving PNECstp by the assessment method.

Sulphamidic acid, a very well water soluble inorganic substance, there is no potential for bioaccumulation through the food-chain, and hence secondary poisoning is not relevant to this substance. Therefore, no PNECoral is derived and no risk assessment on secondary poisoning is performed.

Conclusion on classification

Based on data available, sulphamidic acid is not required to be classified for acute or chronic aquatic toxicity according to CLP Regulation EC No 1272/2008. This is because the EC50/LC50 values found for acute aquatic toxicity tests in fish, daphnia and algae is 70.3 mg/L, 71.6 mg/L and 48 mg/L, respectively and chronic aquatic toxicity data, newly established, do show that long term aquatic toxicity to fish, daphnia and algae is also fairly low (NOEC of 60 mg/L, 19 mg/L and 18 mg/L, respectively). Considering, that sulphamidic acid is an inorganic substance, for which the concept of biodegradability is not applicable and very well soluble in water (181 g/L), indicating no potential for bioaccumulation, classification for acute or chronic aquatic toxicity is not justified.

However, sulphamidic acid has been added to Annex VI to the CLP Regulation with a harmonized classification with R52/53, or aquatic chronic 3 (H412), respectively. This classification was determined prior to the availability of chronic aquatic toxicity data and thus this harmonized classification should be re-assessed in the light of new data being available.