Reaction mass of sodium 1-methoxy-1-oxohexadecane-2-sulphonate and sodium methyl 2-sulphooctadecanoate

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Persistence Assessment

There is conclusive evidence that the main component (>45% - <85%) of the reaction mass (C16MES) is readily biodegradable. Similar substances also reveal ready biodegradability.

On the second component (C18MES), there is a lot of supporting information available which, taken in weight-of-evidence, lead to the conclusion that also this substance can be considered as readily biodegradable. Also the CESIO (a sector group of CESIO) Recommendations for the classification and Labelling of surfactants as "Dangerous for the environment" (April 2003), also state Sulpho-C16 -18 -fatty acid methylester as readily biodegradable.

Based on the results of the main components, it is judged that the reaction mass is also ready biodegradable.

Therefore, the criterion for Persistency is not met.

Bioaccumulation Assessment

The proposed approach in the Guidance on information requirements and chemical safety assessment R.7.1.8 for surfactants was followed. Thus the comparison was performed of measured solubilities in octanol and water, using for the latter the critical micelle concentration in water as the solubility limit.

Calculated values for both components were below logKow 4.5 and thus the substances would be both assigned as not B and not vB.

Toxicity Assessment

The EC50 or LC50 of algae, daphnia and fish for both components were > 0.1 mg/L. Therefore, the screening criteria for T were not met. The NOEC of the long-term Daphnia were > 0.01 mg/L, so the definitive criteria for T were also not met. Furthermore, the substance is not classified as carcinogenic (cat 1 or 2), mutagenic (cat 1 or 2) or toxic for reproduction (cat 1, 2 or 3) nor is there other evidence of chronic toxicity.