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The present study investigated contamination of polybrominated diphenyl ethers (PBDEs) in sediment and fish samples collected from rivers in Guiyu, China where electronic waste (e-waste) is recycled and disposed. PBDE congeners with mono-to hepta-brominated and deca-brominated substitutions were detected using 13C12 isotope dilution GC/MS/MS and GC/MS methods, respectively. The total PBDE concentrations ranged from 4434 to 16088 ng/g (dry weight) in Nanyang River bank sediment, from 55 to 445 ng/g in Nanyang River bottom sediment and 51.3 to 365 ng/g in Lianjiang River bottom sediment in Guiyu compared with those from 16.1 to 21.4 ng/g in wastewater discharged from a vehicle repairing workshop in Lo Uk Tsuen in Hong Kong. No PBDE congeners were detected in bottom sediment and fish from Mai Po Marshes in Hong Kong. The mean concentrations of total PBDEs in mixed muscles of tilapia (Oreochromis spp) from Lianjiang River were 115 ng/g wet weight (ww) and from wastewater in Hong Kong were 4.1 ng/g ww. Highest mean PBDE concentration was obtained in liver (2687 ng/g ww), followed by abdomen muscle (1088 ng/g ww) of bighead carp (Aristichthys nobilis) collected from Nanyang River. A significant correlation of concentration of each PBDE congener between sediment and muscle from Guiyu was observed. The present results of total PBDEs in sediment and fish were 10 and 1000 times higher than other studies. Open burning and dumping of e-waste are the major causes of PBDE contamination. [Copyright &y& Elsevier]

Abstract: Epidemiological studies have reported that both ozone (O3) and temperature are associated with daily mortality. However, few studies have explored the interactive effect between O3 and temperature on mortality. Moreover, whether different O3 metrics influence this interaction is still unknown. This study used a Poisson generalized additive model to examine the interactive effects of daily average temperature and O3 on mortality in Suzhou between 2008 and 2009. The results showed that the O3 effects were stronger in cold season and low temperature days. On days with low temperatures (0th–25th percentile), an interquartile range increment in 1-h maximum O3 corresponded to a 15.96% (95% CI: 1.52, 32.45) increase in total mortality and an 18.77% (95% CI: 0.09, 40.95) increase in cardiovascular mortality. On days with normal temperatures (26th–75th percentile) or high temperatures (76th–100th percentile), the estimates were only 2.04% (95% CI: −5.94, 10.69) or 1.65% (95% CI: −3.21, 6.76) for total mortality, and 7.82% (95% CI: −15.21, 37.10) or 6.14% (95% CI: −17.35, 36.31) for cardiovascular mortality. Using an 8-h maximum metric yielded similar interactive effects between ozone and temperature. For total and cardiovascular mortality, evidence indicates that low temperature has a stronger modifying effect on the 1-h maximum and the maximum 8-h average O3 concentrations than the 24-h average O3 concentrations. The interaction pattern of O3 with temperature was less sensitive at different cut-offs for temperature levels and including co-pollutants in the models. Our findings provide evidence that low daily average temperature significantly modifies the acute effects of ozone on daily mortality for both the 1-h maximum metric and the maximum 8-h average metric in Suzhou, China. [Copyright &y& Elsevier]

The seeds of Herpetospermum pedunculosum (Ser.) C.B. Clarke, a well-known Tibetan medicine in China, are rich in kinds of bioactive lignans. In this phytochemical investigation on H. pedunculosum , sixteen undescribed lignans, named as herpedulins A - P together with 24 known ones were isolated from the ethyl acetate extract of its seeds. Their structures including the absolute configurations were determined by HR MS, 1D and 2D NMR experiments, and comparison of their experimental ECD spectra with calculated ones or literature data. High content screening experiments revealed that 9 compounds could promote the expression of farnesoid X receptor in guggulsterone-induced human normal liver cells L02 cells significantly. Further molecular docking results demonstrated that herpedulin E, J and K exhibited best docking scores (9.70, 9.28 and 10.31, respectively). Hydrogen bonding and hydrophobic interactions might contribute to the main interaction of active compounds with FXR. [Display omitted] • Sixteen undescribed compounds were isolated from Herpetospermum pedunculosum. • The absolute configurations were determined via quantum chemical calculations. • 9 compounds could promote FXR expression in guggulsterone-induced L02 cells. • Molecular interactions of compounds with FXR were analyzed by in silico methods. [ABSTRACT FROM AUTHOR]