The performance and design of a dual-bag denitrifying module based on the selective permeability of polyethylene films were investigated. The module contained an inner polyethylene bag enclosing liquid organics (carbon sources) and an outer bag with a biofilm. Firstly, the permeation rates of methanol, ethanol, acetic acid, and propionic acid were set sufficiently high for the compounds to serve as carbon sources of the module. Secondly, two modules, one containing ethanol and one containing acetic acid were applied to the treatment of an inorganic nitrate medium. The stable denitrifying performances of both modules implied that alcohols and acids at high concentrations can serve as carbon sources of the above module without affecting the biofilm. Finally, the performance of the module set in an aerobic tank for an activated sludge process treating organic wastewater was examined. The water quality indices suggested that the denitrifying modules (of the fixed-biofilm type and attached-biofilm type) submerged in activated sludge are applicable to organic wastewater treatment without negative impact.

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The effects of filter paper type and solvent type on the shaking method for the leachability of dioxins contaminated in marine sediments were examined. The leachability test results were significantly affected by the leakage of fine particle-binded dioxins, which was dependent on the type of filter paper used. Moreover, an increase in the solubility of dioxins due to the association with dissolved organic matter and an incomplete desorption due to insufficient shaking time were identified as other influential factors. Because the test results greatly affect the specification of marine disposal sites and thus the total cost of disposal, revision of the solid-liquid separation procedure in the test protocol is needed to reduce the variability in results.

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It has been recognized in recent years that the occurrence of a wide variety of pharmaceuticals in the aquatic environment is chiefly due to secondary effluent from sewage treatment plants, where the residual pharmaceuticals contained may possibly be in the range of ng·L^-1 to μg·L^-1. However, little is still known of the occurrence and behavior of pharmaceutical metabolites such as conjugates, epoxides and hydroxides in an aquatic environment. The authors developed an instrumental analytical method with liquid chromatography - tandem mass spectrometry (LC/MS/MS) for the simultaneous determination of three pharmaceuticals and their five metabolites. The minimum quantifiable level of target compounds was 0.62 to 11ng·L^-1. The developed analytical method was successfully applied to actual environmental water samples taken at a sewage treatment plant and a water purification plant located in the Tokyo metropolitan area. Seven out of eight target compounds were detected in the range of 50ng·L^-1 to 16μg·L^-1 after processing in primary sedimentation tanks in the sewage treatment plant. Six compounds were also detected in the range of 13 to 38ng·L^-1 in downstream river water. Both carbamazepine and its metabolite were persistent in groundwater and even in finished water in the water purification plant.

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