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Administrative data

bioaccumulation in aquatic species: fish
Data waiving:
other justification
Justification for data waiving:

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion

Executive summary:

The substance CAE (fats and glyceridic oils, avocado, unsaponifiable fraction, heat-treated, CAS No.1119235-20-9) is defined as an UVCB substance (substance of Unknown or Variable composition, Complex reaction products or Biological materials). It is composed of glycerides, free fatty acids and unsaponifiables. The detailed chemical characterisation of CAE is presented in section 1.2 of the IUCLID file.

The log Kow of CAE has not been determined experimentally. A literature review was performed for each component. The estimated log Kow values of all components of CAE range between 3.40 and 14.1. No experimental data is available for two alkyl triols; however, their content is very low (1.8% w/w total). Therefore, the log Kow value of CAE is expected to be > 3. Due to this high calculated octanol/water partition coefficient, CAE may have a tendency to bioaccumulate.

However, OECD 305 study is waived based on, technical, exposure and regulatory reasons:

Technical waiving: Before carrying out any of the bioaccumulation tests, the following information about the test substance should be known: - Sensitivity of the analytical technique for measuring tissue and water concentrations of both the test substance and possible metabolites;

- Solubility and stability in water;

- n-Octanol-water partition coefficient.

These pre-requisites are not fulfilled for CAE. Indeed, the solubility in water and the n-octanol-water partition coefficient were only estimated, but not quantified, for the main components of CAE.

Radiolabeling and Analytical Detection The use of radiolabeled CAE is not practical due to its UVCB nature: chemically modified natural substances. Without radiolabelling, the quantification of the parent "cold" ingredients in fish tissues and the identification of their metabolites would be impossible.

Exposure waiving: The readily biodegradability of CAE was assessed in 2 studies performed according to guidance OECD 301B. In the first study, the criterion for ready biodegradability was almost met with 56% and 57% biodegradation of CAE after 28 days. CAE can be considered as inherently biodegradable and therefore non persistent, according to this first study. This result was confirmed with the second study in which CAE was found to be readily biodegradable. The high level of biodegradation of CAE in these studies provides data which supports a non- exposure of aquatic organisms to CAE as there is no direct exposure of the environment to CAE and the indirect contamination is unlikely to pass through the sewage treatment plant into the surface water bodies.

Regulatory waiving Under Directive 86/609/EEC, it would be unjustifiable to use a vertebrate specie to define the bioaccumulation potential of CAE given the high probability that meaningful data would not be obtained given the complexities, technical difficulties and analytical restrictions discussed in this report.

Conclusion Therefore it appears that for technical and exposure reasons, a bioconcentration study according to OECD 305 is neither justified nor feasible for CAE which in any case is not a PBT substance, and should not be conducted according to Directive 86/609/EEC on the protection of vertebrates.