A risk assessment of Copper Pyrithione (CuPT) in Tokyo Bay was conducted using Margin of Exposure (MOE) method. Sources of CuPT in this'study were assumed to be commercial vessels in harbors and navigation routes. Concentrations of CuPT in Tokyo Bay were estimated using three-dimensional hydrodynamic model, ecosystem model and chemical fate prediction model. These models calculate horizontal and vertical distributions of CuPT concentrations with a fine grid scale : 1 km grid and 10 separate layers with a minimum thickness of 2 m. Risk to marine life of Tokyo Bay exists when MOE values are less than Uncertainty Factor (UF). MOEs of Tokyo Bay were estimated with a UF value of 100 using dissolved CuPT concentration resulting from the model. For this scenario, it seemed that the risk exists in the surface layer of harbors, whereas it does not exist in the bottom layer of the whole bay area. Next, as a numerical experiment, scenario simulations were carried out under two premises : one with a UF value of 1000 and the other with the decreased amount of CuPT fluxes in harbors. For the first scenario, the risk was found to exist in the surface layer of harbors and almost all navigation routes, and besides, even in the bottom layer of harbors. For the second scenario, the sea area with risk was narrowed by decreasing concentration of CuPT in harbors.

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Tributyltin (TBT) is a biocidal chemical that has been used primarily as an antifouling agent incorporated into antifouling paints for vessel hulls. However. TBT was found In affect non-target organisms, which led lo the global restrictinn on its use. As a result, organometallic substances, pesticides and other chemicals have been used as alternatives to TBT. These include zinc pyrithione (ZnPT). copper pyrithione (CuPT). pyridine-triphenylborane (PK), SeaNine211, Diuron (DCMU) and Irgarol 1051. Although TBT alternatives have been used for ship hulls, fishing nets and other fishing equipment, they have been mainly used as antifouling paints for ship hulls. Antifouling paints are used for commercial vessels, fishing boats and pleasure boats. Taking total areas of ship hulls into account, we considered only commercial vessels as discharge sources of TBT alternatives. As a result of our surveys, it was found that CuPT was the one used on commercial vessels as a TBT alternative. We conducted literature review on the toxicity of CuPT on aquatic organisms and its uncertainty. As a result, we selected 1.8 μg/L. which was the lowest acute toxicity, as a criteria toxicity data for risk assessment, and concluded that 100 was appropriate　as its uncertainty factor. Ecological risk assessment can be conducted using these toxicity data and uncertainty factor and　estimated environmental concentrations nf CuPT.

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In this study, a mixture of 13 pigment standards was quantified simultaneously using HPLC (High performance liquid chromatography) A standard of mixed 13 pigments (chlorophyll c3, chlorophyll c2, peridinin, 19'-butanoyloxyfucoxanthin, fucoxanthin, 19'-hexanoyloxyfucoxanthin, prasinoxanthin, diadinoxantliin, alloxantliin, diatoxanthin, zeaxanthin, chlorophyll b, chlorophyll a and β-carotene) was confirmed that peak of these pigments clearly were separated during twenty minutes. Acetone was better than ethanol as a dilution solvent of mixture pigment standards. Pigment analysis in field samples (freshwater lake and brackish water lake) was agreed with the results of phytoplankton composition identified by the microscope. It is judged that the identification of phytoplankton in field sample could be determined rapidly by this calibration standard.

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[in Japanese]

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Seasonal variability of the sea surface height (SSH) in the East China Sea and the Yellow Sea was investigated through the study of model simulation and analysis of observed data. The model SSH was compared with the tide-gage data. The simulation results can well reproduce the amplitude and phase of seasonal variability of the tide-gage SSH. The model SSH is also compared with the satellite altimeter data using Harmonic analysis, and they generally showed good agreement in wide area. The sea surface height is high in summer and low in winter. As a factor of this seasonal variability, SSH variability due to the thermal expansion was considered. It was estimated from the surface heat flux data. The SSH fluctuation range is about 15 cm in the East China Sea and 11 cm in the Yellow Sea, respectively. The minimum appears in February and the maximum appears in September. However, the fluctuation range of model and altimeter data is about twice of this thermal expansion effect, and the time when the minimum appears is locally different. The amplitude and phase of seasonal variability hence cannot be explained by this thermal expansion effect only. As another factor, dynamical effect due to the wind stress must be important. Winter monsoon burst extrudes the seawater from the northern marginal sea area. This may enhance the amplitude and advance the phase in this area.

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We have already developed ecological risk assessment models for Tokyo Bay and fse Bay, called AIST-RAMTB and AISTRAMfB. Using these models, users can easily estimate environmental concentrations of chemicals and their risk to marine organisms on Windows-based PCs. Based on these models, we developed a similar model suitable for the Seto-Inland Sea, called AIST-RAMSIS (National Institute of Advanced Industrial Science and Technology - The Risk Assessment Model for Seto-Inland Sea : AIST-RAMSIS). Environmental concentrations of chemicals can be estimated only by setting parameters of loading fluxes and calculation period using dialog-based graphic user interfaces (GUI). Using the estimated environmental concentrations of chemicals and their no observed effect concentrations (NOEC) for a target species, either risk to the species or an ecological risk can be determined. The results of environmental concentrations of chemicals and associated risk can be stored as CSV or image format files, and these results can be efficiently used or modified in other applications for other purposes.

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It is generally accepted in paint industry that zinc pyrithiones (ZnPT) in antifouling paints containing copper oxides, may transchelate to copper pyrithiones (CuPT) owing to their metal exchange functions. However, transchelation of ZnPT to CuPT has not been proved by chemical analyses due to the difficulties in measuring both ZnPT and CuPT. To scientifically verify such transchelation, we carried out acute toxicity tests using nauplii of Anemia salina. As the results, 24-h medium lethal concentrations (24-h LCr,„) of ZnPT, CuPT and copper ions were 1.1. 0.1 and 4.0 mg/1, respectively. When concentrations of copper ions were in the range of 0.02—0.32 mg/1, 24-h LC5„s of ZnPT decreased to 0.10— 0.15 mg/1. Similar trends were observed for CuPT. When the concentration of copper ions was 0.01 mg/1. 24-h LC5IJ of ZnPT was 0.20 mg/1, which was higher than that of CuPT. When concentrations of copper ions were 0.08—0.32 mg/1. 24-h LC:i„s of CuPT were 0.10—0.13 mg/1. which was similar to the case of CuPT without copper ions. From these results, even under experimental conditions, it seems that one mole of copper ions reacts with one mole of ZnPT without an excess amount of ZnPT because of high reactivity between them, leading to the subsequent production of CuPT in a short period of time.

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The use and production of tributyltin have been restricted in Japan since 1997. As a result, copper pyrithione (CuPT) and zinc pyrithione (ZnPT) have been used in antifouling paints for large vessels as the alternatives, and their use has increased. In addition, it is generally accepted that ZnPT may transchelate to CuPT under the presence of copper ions contained in antifouling paints. CuPT is important as an antifouling compound, but there are few data regarding its toxicity to marine organisms. Therefore, to understand its toxicity, we carried out acute toxicity tests, in which Bafununi (Hemicentrotus pulcherrimus) was used at test species during its early developmental stages. Development inhibition of Bafununi by CuPT or ZnPT was sorted for 4 types ; 1) unfertilized, 2) normalformation coupled with developmental delay, 3) malformation without developmental delay and 4) malformation coupled with developmental delay. Then, EC-30s of CuPT and ZnPT were determined. Malformed individual organisms coupled with developmental delays increased under the influence of CuPT. 24-h and 48-h EC50s of CuPT were 0.0076 and 0.0043 mg/1. respectively. LOEC and NOEC of CuPT were estimated to be 0.0018 mg/1 and 0.001 mg/1, respectively. Malformed individual organisms with or without developmental delays increased under the influence of ZnPT. 21-h EC50 of ZnPT was 0.072 mg/1. Based on these results, it seems that toxic functions of CuPT may be different from those of ZnPT to Bafununi during its early developmental stages.

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Since September 2003, the reception and analyses using level 1 image processing system MEOS (Multi Mission Earth Observation Station) for Terra, Aqua/MODIS data have been carried out in Awara Space Radio Observatory (ASRO) of Fukui University of Technology. In addition to the basic image processing system MEOS, MEOS POLAR Meteorological Processing System which can produce MODIS level 2 products, was newly introduced into ASRO in September 2005. In this report, we show the receiving and data processing system for Terra, Aqua/MODIS data installed at ASRO.

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