Relative Importance of Ingested Sediment and Pore Water as Bioaccumulation Routes for Pyrene to Oligochaete (Lumbriculus variegatus, Müller)
It is generally accepted that sediment ingestion is an important route in accumulation of highly hydrophobic sedi ment-bound contaminants. The significance of this route is, however, difficult to quantify reliably. For this purpose, the relative importance of pore water and ingested sediment as sources was studied by exposing individual oligochaetes of different size to radiolabeled pyrene spiked lake sediment for 28 days. Simultaneously, their ingestion behavior (egestion rate) was followed. The design allowed comparison of the bioaccumulation process between individuals ingesting and noningesting sediment. Pyrene accumulated mainly through ingested material. After 8 days of exposure, approximately 61% of the body burden had accumulated via ingested material. Uptake clearance rates differed between worm groups, which started sediment ingestion at different points of time. This was probably due to decreasing bioavailability. The data signify the importance of ingested material in bioaccumulation of hydrop...