In this study, methods for setting environmental management reference concentration in the air (CMA) and in the water (CMw) for protecting human health are proposed. CMA and CMW are defined as the concentrations at which continuous exposure to the human population is estimated to have no appreciable risk of adverse effects over a lifetime. CMA was estimated using the data from Japanese Air Quality Standard and guideline values, WHO Air Quality Guideline values, RfC and UR of the U.S. EPA, or the threshold limit values stated by the ACGIH or the Japan Society for Occupational Health. CMW was estimated using the data from Japanese Water Quality Standard and guideline values, WHO Water Quality Guideline values, ADI of the Japanese government or the JMPR, RID or UR of the U.S.EPA. A method to determine the contribution of drinking water to the total intake based on the physical properties of substances was developed to calculate the CMW using ADI or RfD. The CMA values of 185 substances and CMW values of 219 substances were obtained by applying this method to substances subject to PRTR. The method proposed and the data estimated in the present study will promote the self-management of facilities dealing with environmentally hazardous substances.

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The use of organophosphorus compounds with high toxicity, a group of poplar agrochemicals, is now prohibited. Therefore, large amount of these compounds are still stored in agricultural farms. It is known that organophosphorus insecticides are decomposed by alkali, but its kinetic study has not been reported yet. In this paper we report the kinetics of the decomposition of five organophosphorus insecticides. The rates for three were found to be first-order with suspect to alkali and organophosphorus compound respectively, while the rates for the other two were too fast to be quantitatively determined under the applied condition. Second-order rate constants were determined at different temperatures. Reaction rates were found to depend on their structures. Decomposition products identified by GC-MS were all nontoxic substances. Thus, alkali decomposition was found to be an efficient method to decompose organophosphorus insecticides.

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This study investigated in a copper recycle rate to meet a growing world copper demand in the 21^st century. The demand scenarios, which were generated in other study, are based upon the IPCC (Intergovernmental Panel on Climate Change) SRES (Special Report on Emissions Scenarios). In this study, we developed a mathematical model that describes supply side of mineral in the world 21^st century that satisfies the generated demand scenarios via discounted sum of total supply cost of mining/milling, smelting/refining, transportation (i.e., imports and exports), recycling, and stockpiles . Feasible solutions for all the copper demand scenarios can be found by the model under the following conditions; i.e., (i) production increment of virgin copper are allowed to double within a decade, (ii) recycling rate is allowed to increase to 90 % at maximum of total final refined copper demand, and (iii) the recycling rate can be increased by 2 .5 times within a decade. We conclude that significant promotion of copper recycling will be required to satisfy expected future increase of copper demand by solely recycling .

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Though a large number of studies, data, and sustainability schemes in daily lives can be found in different sources, only a limited portion of them are referred to by consumers for the purpose of putting the recommendations into action and managing their household consumption activities in a more sustainable manner, because they are not accessible in systematic and appropriate ways. In this paper, we present our approaches to developing an automated system that supports consumers in retrieving the relevant information, manage their daily activities, and learn the issues that are directly and indirectly related to their individual pattern of household consumption, by using environmental balance sheets that are progressively and automatically customized to individual consumer. Activity model of such a management system was constructed using IDEF 0 function modeling language. Using the model, a preliminary trial of the modeled management system was performed using prototype environmental balance sheets, to verify the information flows and to obtain administrative knowledge of such a system.

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The interference of NO_x with the photochemical O_xidant monitoring by KI methodbased instrument was re-evaluated. NO_x interfered linearly with the O_x measurementregardless of the NO₂/NO ratio. The extent of the NO_x interference could be expectedfrom O_x-NO_x plot when monitored simultaneously. An average of 3.7 % was estimatedfor the interference rate in the routine monitoring data. The interference of NO_x could occupy as high as 30 % of observed O_x concentration under high NO_x conditions intraffic hours. A case study showed that the annual average of day-time O_x concentration was lowered by about 3 ppb when the NO_x interference was corrected. Thus the data of routine monitoring for O_x in the urban sites seemed to have been affected strongly by the NO_x interference.

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As the risk assessment of chemicals on ecosystem is the matter of major concern, the chronic toxic effects of chemicals on aquatic organisms such as fish recently considered to be more critical than the acute toxic effects. Emphasis has shifted to chronic toxicity tests such as full life cycle, partial life cycle and early life cycle (ELS) tests. In Japan, the acute toxicity test for marine fish has been performed on fish species for aquaculture such as red sea bream (Pagrus major), black sea bream (Acanthopagrus schlegeli), however a method for the chronic toxicity test for these fishes not yet been established, because of the difficulty of keeping the fish at early life stage. Therefore, based on the assumption that the acute-to-chronic toxicity ratio (ACR) for a given toxicant is relatively constant over a range of test specie, an attempt was made to obtain ACR from mummichog (Fundulus heteroclitus). We tested this species for acute and ELS tests and obtained ACR. The estimated ACR from mummichog can be applied to Japanese marine fish species for which a NOEC cannot be easily derived

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[in Japanese]

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A marine rotifer Brachionus plicatilis was exposed to 2-ppm of fenitrothion, a representative organophosphorus insecticide, and cultivated on a minute alga Tetraselmis tetrathele by a water-flow continuous cultivation system for 1037 days. The fenitrothionexposed B. plicatilis was subjected to examination for influences on tolerance and metabolism toward fenitrothion and other organophosphorus insecticides, such as salithion, phenthoate, dichlofenthion, cyanophos, diazinon and malathion. Tolerance of B. plicatilis estimated by the 50 % lethal concentration (LC₅₀ value) of an insecticide was improved to tested insecticides except for malathion and phenthoate. The LC₅₀ value of fenitrothion for B. plicatilis exposed for 1037 days was 9.2 ppm and it is greater than 5.4 ppm for non-exposed B. plicatilis. Metabolism ratios to tested insecticides of the exposed B. plicatilis were also improved and risen upto 100 %. B. plicatilis altered ability to metabolize almost quantity of insecticide taken into the body from ambient water. To explain the alterations, measurements of bioconcentration factor and metabolism of 14C-labeled fenitrothion were demonstrated with the B. plicatilis. Alterations of tolerance and degradation were assumed due to alteration of balances among ratios for uptake, clearance and metabolism, and improved metabolic activity toward insecticides by the fenitrothion exposure.

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I evaluated the toxicity of polluted waters using sea urchin bioassays. The water samples tested showed inhibitory effects on the life cycle of sea urchins in the descending order of sensitivity of gametogenesis, sperm + egg, sperm, egg, metamorphosis, pluteus, gastrula, fertilization, cell division, blastula and adult . In most cases, sperm and eggs placed in the test water underwent fertilization and subsequent normal development. Abnormalities such as polyspermy (multi-polar division), permanent blastula, developmental delay, gastrula lacking the normal structure, spaceship Apollo-like gastrula, exogastrula, radialized embryo and others were identified in samples containing various heavy metals including zinc, nickel and others. Bioassay of samples taken over 34 years around Tanabe Bay, Wakayama Prefecture, Japan, showed the presence of marked pollution at some sites during the years 1970-1976 and 1982-1987. The former years may represent the normal degradation of pollution, whereas the latter may have been the result of TBT pollution arising from the use of anti-fouling paint for fishing cages and boats. Effluents from disused mines was also identified with this bioassay and chemical analysis. Various zinc-dependent and other abnormalities of development were observed.

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Bioassays play several important roles in management of marine environment ; 1) toxicological assessment and criteria setting of chemicals; 2) hazard assessment and regulations of point sources discharged into marine environment; 3)toxicological assessment of chemicals carried by ships; 4) toxicological assessment of dredged material, sediment and waste material for ocean dump; 5) monitoring of coastal waters. Recently the battery of ecotoxicological tests have become a prerequisite for chemical control law and the environmental quality standard for the protection for aquatic organisms has been established in Japan, which would reduce the land-based chemical input to marine environment. However, the toxicological databases on marine species should be developed to promote these processes. The regulations on effluents and toxicological assessment of sediments with bioassays that have been conducted in some countries would be valuable in Japan as well. To meet the increased demand for chemical assessment, various kinds of marine bioassays have been developed recently in Japan. As for the monitoring of coastal environment where chemicals have been diffused and diluted, sensitive bioassays including biomarkers are necessary. Several Japanese pioneering works of monitoring of coastal environment based on bioassay were introduced and the present problems have been discussed. Contrary to Japanese situation, bioassay has been adapted successfully as diagnostic tools for the health of ecosystem at Mediterranean and other sea. Finally, the significance of introduction of bioassay into the framework of routine coastal monitoring was highlighted and the challenges to be overcome were presented.

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