Porous polydimethylsiloxine (PDMS) membranes were prepared using polyethylene glycol (PEG) as pore forming agent. After the PDMS-PEG membranes were prepared, they were immersed in hot water to remove PEG from the membranes to prepare the PDMS porous membranes. A dense PDMS membrane was also prepared. The degree of weight swelling of the membranes in toluene increased with an increase in PEG content, indicating the porosity of the membranes increased with PEG content. The solvent permeation across the membranes was measured by low-pressure (0.2-0.3MPa) driven filtration. Pure toluene and waste organic liquid containing fine solid particle (200 µm) and organic solvent were used as feed solutions. Toluene permeation increased with increasing the PEG content. The solid particle weight concentration in waste organic liquid was 7.2wt%, however, almost pure solvent was obtained by the filtration: the solid particle weight concentration was less than 1wt% in permeate.

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Effective extraction of radioactive cesium from the polluted soil into water was achieved by using the detergent composed of an acid, an alkaline metal or alkaline earth metal chloride, and a cellulose dispersant. In particular, the detergent solution consisting of 5% sulfuric acid, 20% magnesium chloride, and 1% hydroxyethyl cellulose showed high extraction ability towards radioactive cesium in polluted soil. By washing the polluted soil twice with this detergent solution, 96% of the radioactive cesium was extracted from the soil.

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Occurrence of organochlorine pesticides (OCPs) including hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), drins, heptachlors, chlordanes, dichlorodiphenyltrichloroethane (DDT) and mirex in 19 food items collected from Shandong Peninsula were investigated and estimated the potential health risk of dietary intake. HCHs (including α, β, γ and δ-HCH) were ubiquitous components in the study area with the highest total concentration found in peanut oil (2.4 ng/g) and the composition of HCHs indicated the mainly historical usage of technical HCHs and recent input of lindane. Although high sum concentrations of DDTs (including o,p’-DDE, p,p’-DDE, o,p’-DDD, p,p’-DDD, o,p’-DDT and p,p’-DDT) were found in croaker (72 ng/g ww), the value was still far below the Chinese safety guidelines (500 ng/g). The composiion of DDTs metabolites revealed the recent input which may be attributed to the antifouling paints leakage from transportation sources. However, the detection of Σ209 polychlorinated biphenyls (PCBs) were only conducted in 5 marine food items with rather lower concentration ranged from 0.33 ng/g to 3.1 ng/g ww. It was interesting that PCB #11 and Hexa-CBs were frequently detected with high proportion to total PCBs compared to other homologues. According to the Integrated Risk Information System (IRIS), the average daily exposure for each contaminant in foodstuffs was lower than the corresponding benchmark concentration based on cancer and non-carcinogenic effects. To date, the work provided the first data about the existence of non-Aroclor PCB #11 in foodstuffs from China and should arouse much attention from a toxicity point.

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