[Show abstract][Hide abstract] ABSTRACT: Semipermeable membrane devices (SPMDs) in combination with in vitro ethoxyresorufin-O-deethylase (EROD) assay was used to assess the aryl hydrocarbon receptor (AhR) effects in aquatic system. In present work, polycyclic aromatic hydrocarbons (PAHs) were selected as target compounds and SPMDs were deployed simultaneously with caged crucian carp for 32 days at five sites in Meiliang Bay, Taihu Lake. The concentrations of PAHs in the SPMD dialysates and fish tissues were analyzed by gas chromatography-mass spectrometry. In addition, the EROD activity of SPMD dialysates was assayed with H4IIE rat hepatoma cells and the induction of EROD activity in pancreas and liver of fish was also assayed. It was found that dialysates from SPMDs with longer exposures generally induced stronger activity and the toxic potency of dialysates expressed as bioassay-derived 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents ranged from 3.8 pg/g to 6.2 pg/g for 32 days exposure. A correlation of toxicity equivalency quantity (TEQ) with chemical analysis and in vitro bioassay-derived TEQ(bio) of SPMD dialysates yielded an R2 of 0.88, therefore, indicated that PAHs were one of the important AhR agonists in the water. Empirical evidence suggests that PAHs can account for about 40% to 50% of the potency observed. Moreover, a good correlation was observed between the results of EROD bioassay in vivo and EROD bioassay in vitro (R2 = 0.62), thus reflected that these two methods can be complementarily each other. It is, therefore, suggested that the SPMD technique combined with chemical analyses and in vitro EROD assay might be a valuable monitoring tool to assess the levels and effects of AhR agonists in water ecosystem.
No preview · Article · Dec 2006 · Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.]
[Show abstract][Hide abstract] ABSTRACT: Semipermeable membrane device (SPMD) was recently accepted to estimate the time-integrated concentrations of bioavailable hydrophobic organic compounds (HOCs) in a similar manner as lipophilic bioconcentration. However few field researches were carried out to verify the similarities of SPMD and fish in concentrating HOCs from water. In present work, SPMD and caged crucian carps (Carassius auratus) were deployed side-by-side at five sites in Meiliang Bay, Taihu Lake for 32 days and concentrations of polycyclic aromatic hydrocarbons (PAHs) in SPMD and fish were analyzed. The results showed that the composition of PAHs and relative concentration of individual PAH in SPMD and fish were quite similar. There was significant correlation between bioconcentration factors (lg BCF) and device concentration factors (lg DCF) for concentrations of PAHs (p < 0.0001). However in a quantitative analysis, lipid-normalized concentrations of PAHs in SPMD and fish were similar, and the ratios of the concentrations of PAHs in fish and SPMD were ranged from 0.47 to 4.12. In summary, SPMD could be the surrogate to estimate PAHs levels in fish in fresh water lake.
No preview · Article · Jul 2006 · Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.]
[Show abstract][Hide abstract] ABSTRACT: The Guanting Reservoir lost its function as the second biggest drinking water source for Beijing due to the pollutions from the upstream flow of Yongding River in 1997. From 1998, lots of studies were carried out to renew the function of Guanting Reservoir as domestic drinking water source before 2008 Olympic Games. This is the first time that polycyclic aromatic hydrocarbon concentrations in the surface sediment of Guanting Reservoir have been analyzed. A distinctive spatial distribution of PAHs was observed. Sediments from four sites along Inlet of Yongding River to reservoir bam had PAHs concentrations of 1377-2855 microg/g dw in descending order. The composition of PAHs is investigated and used to assess petrogenic, combustion and naturally derived of the sediments samples of Guanting Reservoir. Special PAHs ratios, such as phenanthrene/anthracene (P/A) and fluoranthene/pyrene (FI/Pyr) were calculated to assess the relative importance of different origins. The data confirmed a relatively high level of petrogenic contamination in four sites. These high PAHs levels were associated with the input of untreated and partially treated industrial sewage. In addition, the concentrations of PAHs compounds of samples indicated that sediments of reservoir were most likely to pose potential biological impairment.
No preview · Article · Feb 2005 · Journal of Environmental Sciences