Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

As the surfactant part of the substance is present as sodium carboxylates at environmental pH, the substance is expected to partition predominantly to the aquatic compartment and minimally adhere to organic matter. For the environmental CSA, the Koc of the substance has been calculated based on logKow. The calculated Koc value is 3.16 L/kg. Due to its low vapour pressure, volatilisation is considered negligible. Therefore it can be concluded that the substance will mainly distribute to the freshwater compartment. Distribution to other environmental compartments is considered to be negligible.

Surfactants used in household detergents today are generally readily biodegradable and efficient removal can be expected in well-functioning biological wastewater treatment plants (WWTPs). A high removal efficiency for various non-ionic and anionic surfactants (>99%) has been demonstrated in a study carried out in the Netherlands (Matthijs et al. 1999). This study showed that although some removal of surfactants was observed in the primary settling, biological degradation accounted for most of the removal. Based on this information, a removal efficiency of 98% in municipal sewage treatment plants by degradation could be used in the CSA, as was used in the earlier version of the CSA (resulting in an effectiveness water of 98.03%).

As meanwhile the environmental hazard assessment has been significantly refined, it was not necessary to implement this refined removal efficiency by degration in the CSA update, as safe use was already shown by using the percentages as calculated by the SIMPLETREAT model integrated in EUSES (resulting in an effectiveness water of (only) 87.35%).

Still, the removal of this substance in biological wastewater treatment plants by degradation under actual environmental conditions is considered to be higher than calculated and used in the CSA of this substance.