Registration Dossier

Administrative data

Endpoint:
bioaccumulation: aquatic / sediment
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Despite the fact that the log Kow is measured applying the most appropriate method according to the REACH guidance i.e. the slow stirring method (OECD 123), there is unfortunately no reliable relationship between the measured log Kow and BCF for this type of substances. The predicted low bioaccumulation potential is however supported by the low acute to chronic ratio observed in the long-term daphnia test. The daphnia reproduction test result for e.g. DETA based imidazoline shows that at 810 μg/L all parental daphnids were immobile within four days, without reproduction, while at the next concentration of 270 µg/L not only is there no immobilisation, but there is no detrimental effect on reproduction when compared to the control. These observations results in the derivation of a NOEC of 270 µg/L resulting in a low acute-to-chronic ratio. A low acute-to-chronic ratio is indicative of a non-specific mode of action and is often associated with not systemic effects. This observation is consistent with the known effects of cationic surfactants on aquatic organisms, where toxicity is associated with physical binding to respiratory membranes. This explains the steep concentration curves seen and the lack of intermediate chronic effects on reproduction.
Data waiving:
study technically not feasible
Justification for data waiving:
other:

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion