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In this paper, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured in biota (reed, grass, mussel, fish, and red-crowned crane) and sediments collected from seven locations in the Zha Long Wetland. PAHs were recovered from the sediments and biota by ultrasonic extraction and then analyzed by means of gas chromatography-mass spectrometry. The total PAH concentrations were 244-713 ng/g dw in sediments, 82.8-415 ng/g dw in plants and 207-4,780 ng/g dw in animals. The total sediment PAH concentrations were categorized as lower to moderate contamination compared with other regions of China and the world. In the plant samples, the accumulation abilities of reed roots and stems for PAHs were higher than those of grass roots. In addition, the concentration of individual PAHs in mussel muscles was the highest in all of the animal samples, followed by fish, feeding crane fetuses, and wild crane fetuses. Compositional analysis suggests that the PAHs in the sediments from the Zha Long Wetland were derived from incomplete biomass combustion. Risk assessment shows that the levels of PAHs in sediments are mostly lower than the effects range mean value (effects range mean), whereas only naphthalene in all sample sites was higher than the effects range low value. It is worthwhile to note that benzo(b)fluoranthene, benzo(k)fluoranthene, indeno(1,2,3-cd)pyrene and benzo(ghi)perylene were detected in crane fetal, which have potential carcinogenicity for organisms from the Zha Long Wetland.

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2013) Inhibition effects of pentachlorophenol (PCP) on anaerobic digestion system, Desalination and Water Treatment, 51:28-30, 5892-5897, A B S T R A C T Pentachlorophenol (PCP), a kind of ionizable hydrophobic organic contaminant, had been extensively used in agricultural, industrial, and domestic applications as an important component of fungicides, bactericides, herbicides, insecticides, biocides, and wood preservatives, To investigate the effects of pentachlorophenol (PCP) on anaerobic digestion system, an experimental study was carried out in which simulated PCP-contaminated sewage water was treated using a batch reactor. The study revealed that the influences of PCP on acidogenic and methanogenic microorganisms. Affected by PCP, the fermentation type of system was transformed from butyric acid type to propionic acid type.Moreover, biogas production rate and methane content were less. PCP inhibited the activity of methane bacteria significantly: during the series of PCP addition (PCP concentration was 0, 14.9, 19.1, and 29.5 mg/ L, respectively), the higher the PCP concentration was, the more serious the inhibition effect was. The removal rate of PCP was 94.6% when the PCP concentration was 14.9 mg/L, while it was only 54.8% when PCP concentration was raised to 29.5 mg/L. Acidogenic microorganism was more quickly adaptable for PCP than methanogenic microorganism.

Different distributions of HCHs, DDTs, and other OCPs indicated that they originated from different contamination sources. Composition analyses in surface sediments indicated recent OCP usage or discharge at some sample sites in the Zha Long Wetland.

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