Bioaccumulation of Methyl Siloxanes in Common Carp (Cyprinus carpio) and in an Estuarine Food Web in Northeastern China

Despite the high production volume and widespread use of methyl siloxanes, limited studies have been conducted to investigate the bioconcentration, biomagnification, and trophic magnification potentials of these substances. In the present study, bioconcentration factors (BCFs) of methyl siloxanes were determined with common carp exposed at environmental relevant levels for 32days. BCF of octamethylcyclotetrasiloxane (D-4) was estimated as 6197L/Kg, indicating strong bioconcentration potential in the common carp. To assess the food chain transfer of methyl siloxanes, 12 aquatic invertebrates and vertebrates species were collected from a food web in Shuangtaizi estuary in northeastern China and concentrations of methyl siloxanes in these species were determined with gas chromatography mass spectrometry. Trophic magnification factors (TMFs) of decamethylcyclopentasiloxane (D-5), dodecamethylcyclohexasiloxane (D-6), and linear siloxanes (L7-10) were significantly greater than 1 in one food chain selected, which suggest trophic magnification potentials of these methyl siloxanes. Biomagnification factors of D-4-D-6 and L-7-L-10 from planktons to Japanese snapping shrimp were greater than 1, indicating biomagnification potentials of these methyl siloxanes from the prey to predator. This is the first study to investigate the bioaccumulation behaviors of methyl siloxanes by coupling BCF and BMF with TMF.