Dioxin transfer from sediment to the infaunal surface deposit‐feeding polychaete Perinereis nuntia in a laboratory‐rearing experiment

In the presented study a laboratory experiment was conducted to investigate the transfer of polychlorinated dibenzo‐ p ‐dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin‐like polychlorinated biphenyls (PCBs) from environmentally contaminated marine sediment to an infaunal surface deposit‐feeding polychaete, Perinereis nuntia . Polychaetes were exposed to contaminated sediment for 42 d, and elimination of these compounds was studied for an additional 28 d. The sediment uptake rate coefficients ( k s ), elimination rate constants ( k 2 ), and the biota‐sediment accumulation factors (BSAFs) were determined for PCDDs, PCDFs (PCDD/Fs), and dioxin‐like PCBs. Each of these compounds was transferred from sediment to polychaete except for hepta‐ and octachlorinated PCDD/Fs. The BSAFs for dioxin‐like PCBs (0.13–2.2) were significantly higher than those for PCDD/Fs (0.00022–0.36). The BSAF, k s , and k 2 values obtained in the present study indicate that the bioaccumulation characteristics of PCDD/Fs in polychaete are similar to those in fish, and depend on their physical and chemical properties such as hydrophobicity and size of molecules. The k s values for PCDD/Fs and dioxin‐like PCBs declined with an increase in their log K OW values, indicating a decrease in bioavailability. The negative exponential relationships of k 2 versus K OW were observed for these compounds. The slope for the log‐normalized regression of k 2 versus K OW for the PCDD/Fs was smaller than that for the dioxin‐like PCBs and that of k s versus K OW for the PCDD/Fs. Therefore, the negative exponential relationship of BSAF versus K OW was observed for PCDD/Fs, but not for dioxin‐like PCBs. Environ. Toxicol. Chem. 2010;29:1512–1519. © 2010 SETAC