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A theoretical study of axial water exchange on glycinatocopper(II) is presented by using density functional theory (DFT) calculations where several water molecules in the close vicinity of the axial position of the complex were explicitly coordinated to Cu besides the conductor-like polarizable continuum model of hydration. It resulted in obtaining two types of five-coordinate complexes in which the third glycine was bound through the amino and carboxyl group respectively.

Tissue distribution is an important property of pharmacokinetic behaviors of dioxins to provide information for risk assessment to wild avian species. In this study, concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (coplanar PCBs) were determined in muscle, liver, spleen, kidney, brain, and adipose of wild herring gulls collected from Bohai Bay, North China. Tissue distribution results showed preferential accumulation of PCDD/Fs in liver and of co-PCBs in adipose. The congener patterns of coplanar PCBs were constant in different tissues, but the congener patterns for PCDD/F were tissue-specific. The liver/adipose concentration ratios for PCDD/ Fs were found to increase statistically significantly with log K(ow), providing the quantitative relationship of structure-activity for hepatic sequestration of PCDD/Fs for the first time. Furthermore, this relationship was compared with those developed on the basis of previous results reported in the literature showing that the wild herring gulls in Bohai Bay are still in the exposure period.

Many investigations have highlighted the bioaccumulation of dioxins in animals, but little is known about the trophodynamics of dioxins in the food web. In this study, the trophic transfer of nine dibenzo-p-dioxin (PCDD) congeners, eleven dibenzofuran (PCDF) congeners, and twelve non-, mono-ortho polychlorinated biphenyl (non- and mono-ortho PCBs) congeners in a marine food web were determined. The concentrations of PCDDs, PCDFs, non- and mono-ortho PCBs were analyzed in phytoplankton/ seston, zooplankton, three invertebrate species, six fish species, and one seabirds species collected from Bohai Bay, representing approximately 4 trophic levels based on stable nitrogen isotope values. Positive relationships were found between trophic levels and lipid equivalent concentrations of non- and mono-ortho PCBs except for PCB-77, PCB-81, PCB-126, PCB-156, and PCB-167, indicating bioaccumulation of these compounds in this food web. But lipid equivalent concentrations of low chlorinated 2,3,7,8-substituted-PCDD/Fs did not exhibit statistically significant trends with trophic levels. And lipid equivalent concentrations of high chlorinated 2,3,7,8-substituted-PCDD/Fs and three non-2,3,7,8-substituted-PCDD/Fs declined significantly with increasing trophic levels providing that these isomers undergo trophic dilution. The similarity in log Kow values for non-, mono-ortho PCBs, non-2,3,7,8-substituted-PCDD/Fs, and some 2,3,7,8-substituted-PCDD/Fs suggests that the difference of trophic transfer is mainly due to their different metabolic transformation rates.