Fatty acids, C18-unsatd., reaction products with acrylic acid and polyethylenepolyamines

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species: fish

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Description of key information

No measured or calculated BCF values have been presented for components of this UVCB substance, mainly due to limitations in validated experimental or predictive methodologies for determining Kow for surface active substances, and the technical considerations for testing a UVCB substance composed of surface active homologues.  It is believed that the substance will have a low tendency to bioaccumulate based on the fact that these substances will adsorb strongly to suspended or dissolved materials in the marine environment, becoming bio-unavailable, and be removed from the pelagic environment to the sediment.  Once in the sediment, the material is non-toxic to sediment dwellers and will then biodegrade.  Should any of this chemical substance be adsorbed into organisms, it is also expected to metabolise fairly quickly.

Assessment of terrestrial bioaccumulation is not a standard data requirement under Regulation (EC) 1907/2006.

Additional information

An inherent property of chemicals with surfactant properties such as those found in fatty acids, C18-unsatd., reaction products with acrylic acid and polyethylenepolyamines is that they accumulate at the interface between phases rather than equilibrating between phases. Therefore, the accurate measurement of the log K_owof any chemical with surface-active properties is difficult. Even if such measurements were made accurately, the log K_owmay not be an appropriate value by which to predict the partitioning behaviour of this group of chemicals in the environment because of the tendency of surfactants to partition at lipid/aqueous interfaces. In addition, the OECD Guidelines (107/117) for determination of the Partition Coefficient indicate that neither method is applicable to “surface-active materials” (Guideline107) or “surface-active agents” (Guideline117). Similarly, values from the models should be considered to represent only one of several components in these products

QSARs and experimental techniques for measuring this parameter are available. The recommended model for log K_owup to 6 is Veithet al. (1979), whereas for chemicals with log K_ow6, a parabolic equation, recalculated from that described by Connell and Hawker (1988), is recommended. In general (Q)SAR models should only be used for those chemicals that fall within the domain of the model and for which the descriptors are suitable (EC 2003; ECETOC 2003). Surfactants are clear examples of organic materials outside the scope of (Q)SAR models that use log K_owbecause it is not an appropriate physicochemical descriptor for such materials.

The physical and chemical characteristics of cationic surfactants have been more widely investigated than their environmental effects. Most of these surfactants are relatively insoluble in water, form complexes with dissolved organics, particularly with anionic compounds, and are strongly adsorbed onto solids.

Environmental release of fatty acids, C18-unsatd., reaction products with acrylic acid and polyethylenepolyamines will occur exclusively in the marine environment, where concentrations of suspended solids and organic matter are high. Such an environment would result in adsorption of this cationic substance to suspended solids and organic matter; i.e. the material in the pelagic phase with negatively charged surfaces. Strong sorption to these suspended or dissolved materials would render fatty acids, C18-unsatd., reaction products with acrylic acid and polyethylenepolyamines bio-unavailable to organisms for bioaccumulation. In addition, if any of this chemical substance is taken up by organisms, such long chain fatty acids are known to be extensively metabolised in fish and when structural alerts for bioaccumulation from this substance are entered into OECD toolbox, the results indicate they will be metabolised quickly.

In summary, there are no measured or calculated BCF values presented for components of this UVCB substance, mainly due to limitations in validated experimental or predictive methodologies for determining K_owfor surface active substances, and the technical considerations for testing a UVCB substance composed of surface active homologues. It is believed that the substance will have a low tendency to bioaccumulate based on the fact that these substances will adsorb strongly to suspended or dissolved materials in the marine environment, becoming bio-unavailable, and be removed from the pelagic environment to the sediment. Once in the sediment, the material is non-toxic to sediment dwellers and will then biodegrade rapidly(half-life between 15-30 days). Should any of this chemical substance be adsorbed into organisms, it is also expected to metabolise fairly quickly.