Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

The substance distillates (coal tar), heavy oils (anthracene oil >50 ppm BaP, AOH [CAS no. 90640-86-1]) is a UVCB and consists of a complex combination of polycyclic aromatic hydrocarbons. It comprises mainly3- and 4-ring aromatic compounds and to a much lesser extent PAHs with 5 rings (see Chapter 1.). Main components are phenanthrene, anthracene, fluoranthene and chrysene. Benzo[a]pyrene is present at a typical concentration of below 1%.

Due to the complex composition of UVCB, it is technically not practical in many cases to measure their environmental fate properties applying standard tests. To compensate for this characteristic, available data of related substances are used as substitute/supporting substances.

As AOH is composed of PAH, data for this class of compounds will be used to describe the environmental fate properties of AOH in case information requirements are not fulfilled by AOH specific data. Data originating from PAH are assessed to characterise properties of AOH satisfactorily.

Emphasis will be laid on the main components of AOH (see above). In order to derive data characteristic of the total of AOH, available data will be assessed and used in such a way that they represent AOH as whole. In case a distinct value is required, individual data may be averaged or the most representative result will be selected. Justification is given under the individual endpoints.

Overall environmental fate and pathway characteristics of AOH

Components of AOH (PAH) are not hydrolysable, since they contain no hydrolysable groups.

They are not readily biodegradable, but few of them are considered to be inherently biodegradable, e. g. phenanthrene. As the higher PAH fluoranthene and pyrene are present in AOH as well, the intrinsic characteristic of PAH is assessed as not being biodegradable.

Components of AOH (PAH) have a moderate bioaccumulation potential, reliable BCF values in fish ranging below 2000, only for anthracene and phenanthrene extending apparently beyond 2000. On the other hand, experimental evidence and experience have demonstrated that PAHs show no biomagnification in the food chain (Lampi and Parkerton 2009) (WHO 2003).

Adsorption to soil is supposed to vary according to soil composition and adsorption coefficients of individual substances. Estimates for Koc range from about 23,000 (phenanthrene) to approximately 90,000 (pyrene) giving the range for main components of AOH. An individual average characteristic Koc value for AOH is estimated to be ca. 60,000.

Reference:

Lampi M and Parkerton T (2009):Bioaccumulation Assessment of PAHs, Review Paper Prepared for CONCAWE by ExxonMobil Biomedical Sciences, Inc., October 2009).

WHO (2003). HEALTH RISKS OF PERSISTENT ORGANIC POLLUTANTS FROM LONG-RANGE TRANSBOUNDARY AIR POLLUTION, JOINT WHO/CONVENTION TASK FORCE ON THE HEALTH ASPECTS OF AIR POLLUTION. WHO Regional Office for Europe, World Health Organization 2003