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Organotin compounds have been used in antifouling paints and pesticides. which act as the endocrine disruptor to some of the marine organisms. In Japan, usage and imports of them are legally restraint by low a couple of decades ago. However, organotin compounds are the problem because they remain still in the sea water and sediment. In this study, we collected surface sediment samples from Okinawa coastal area and analyzed by using GC-FPD. We found that there are organotin compounds with high concentration at some of the sampling sites. We also collected sediment core samples from the high concentration site to investigate the vertical distribution and temporal variation of the organotin compounds.

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Lake sediment cores in Lake Biwa, collected from the northern and southern basins, respectively, were measured for carbon content, d¹³C, and d¹⁴C. Acid-alkali-insoluble fraction (residue) and acid-soluble fraction obtained by acid-alkali-acid treatment of the sediments were analyzed. The sediments in rivers flowing in Lake Biwa were also measured for C content and d¹³C of residue and acid-soluble fractions. The d¹³C and d¹⁴C values of residue were higher than those of acid-soluble fraction. We will report the difference, together with the result of different chemical behaviors of sediments in the northern and southern basins.

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The purpose of my study was two fold: (1) Determination of the occurrence of Trihalomethanes (THMs) in the drinking waters in Okinawa and (2) determination of the factors that correlated with the formation of Trihalomethanes (THMs) compounds including pH, temperature bromide concentration and Total Organic Carbon (TOC). Despite the new technology of treating water (e.g.) ozonation, the people still need to be aware and make sure is safe and secure from water pollutants. The concentration of THMs were well below the WHO compliance and the EU Maximum Contamination Level.

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My aim of this study is to determine the concentration of heavy metals in surface sediments collected from Naha port and Tomari port in Okinawa, Japan, to establish the forms in which the metals exist in the sediments by carrying out a sequential extraction procedure on the sediments and to determine if the levels can be considered to be a threat to the aquatic organisms in the water. Since heavy metals are stable and persistent contaminants of coastal environments and their presence in the aquatic ecosystem has a far reaching implications directly to the biota and indirectly to man, there is a need to monitor their concentrations to ensure that they are below the toxic levels.

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The chemical and mineralogical compositions were studied to quantify and compare the nutrient disribution for the three geological forest soils (limestone, marlstone and silicate rocks). Three sampling poits were established for each soil type in which samples were taken from surface (0-10 cm) and subsurface (10-20 cm).The mineralogy of clay fractions at all three sites was dominated by kaolinite and illite, while quartz was a dominant in the silt fractions. All soil samples from silicate rock were strongly acidic with pH ranged from 3.6 to 5.6, while that from limestone and marlstone sites were typically neutral to slightly alkaline.In generally,limestone soil is much enriced with nutrints as compared to marlstone and silicate rocks.

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Measurements were performed from June 2003 to January 2005 in Yokohama city, Kanagawa prefecture, Japan. The species in this study were OC, EC, ions(6), metals(9). The source contributions for PM2.5 in this site were estimated by using Positive Matrix Factorization (PMF). The results showed that eight sources were identified: gasoline-powered vehicles(32%), secondary aerosol(NO3-)(10%), oil combustion(8.4%), sea salt(4.0%), incineration(4.9%), soil(2.4%), metal(10%), secondary aerosol(SO42-) & diesel-powered vehicles (28%). In conclusion, it would be necessary to be enforced emission standards for not only diesel-powered vehicles, but also multiple sources. In addition, 13C in PM 2.5 was measured in this study. The possibility of source apportionment for PM2.5 using 13C was investigated.

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We analyzed eondocrine disrupters nonylphenol (NP) and bisphenol A (BPA) concentrations at various sites located adjacent to coral reefs in Okinawa, Japan. In order to evaluate possible contamination of coral reefs by NP and BPA, we analyzed seasonal variation and spatial distribution of NP and BPA. The concentration of NP in sediment samples varied irregularly with season at almost all sites. The degradation of NP and BPA were studied in the laboratory. This laboratory study showed that main factor of degradation was temperautre. However, the degradation also depended on the characteristics of the sediment such as aerobic/anaerobic condition, grain-size fraction and organic carbon (OC) content.

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Sclero sponge habits in dark caves of outer coral reef, and grows massive skeletons with yearly growth band. In the present study, the analytical results of trace elements, stable and radio isotopes of ¹³C, ¹⁴C and others will be shown. And the clear results on anthropogenic impact to environments will be discussed.

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Li isotopic ratio and its contents were determined using MC-ICP-MS. Li was separated through cation-exchange resin, based on the procedure by Nishio and Nakai (2002). In its application, we report the Li isotopic ratio and its contents of mantle xenoliths from Avacha volcano as fragments of mantle wedge of the Kamchatka arc, and discuss the relationship between Li isotopes and mantle metasomatism.

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Water and major element concentrations have been measured basaltic matrix glass samples from Iceland and the Reykjanes Ridge, the section of the Mid-Atlantic Ridge immediately to the south of Iceland. The results suggest that there is a wetter source beneath Iceland, whose influence increases along the Reykjanes Ridge towards Iceland, i.e. that Iceland is a wetspot. By comparing H2O/Ce for the Iceland and Reykjanes Ridge basalts we will be able to determine if they show an EM or FOZO signature, whether H2O/Ce of Iceland is higher than the surrounding elevated MORB, and therefore whether Iceland is a wetspot, a dampspot, or not wet at all compared to the surrounding MORB source.

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Elucidating the material cycle in the terrestrial mantle is one of the major goals of the field of geoscience. Radiogenic isotopic ratios such as strontium (Sr), neodymium (Nd), and lead (Pb) have been used to track recycled components in the mantle. This study shows that the non-traditional lithium (Li) isotopic tracer has a great potential to provide a major breakthrough in the investigation of the material cycle in the terrestrial mantle.

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In the early 1980s, acid rain became a serious social problem. In 1985, ozone hole was discovered over the Antarctica and the stratospheric ozone depletion has received social attention together with global warming. I have started my atmospheric chemistry with polar organic acids in Los Angeles acid rains. Two decades ago, organic compounds in the atmosphere were believed as trace components. However, we now realize they are abundant (up to 70%) in the fine particles. They are water-soluble and thus can act as cloud condensation nuclei to form cloud droplets. Here, I will review the study of organic acids and the recent progress on organic aerosols in the urban, marine and polar atmosphere and their role in the earth climate system.

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Stalagmites and tufa deposits, terrestrial layered carbonates continuously record the past information on depositional environments. The artificial vegetation change during past 1000 years in Akiyoshi-dai Plateau could be clarified by using d¹³C value of annual layers of a stalagmite . The history of air pollution in Kitakyushu industrial area during past 100 years was extracted in success from tufa deposits by measuring the sulfate contents of their annual layers.

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A submerged calcite speleothem sample from Inazumi Cave, Oita, was dated by TIMS. The speleothem became submerged by accumulation of the Aso welded-tuff. The age of the analysed portion of the sample was 170,000 years B.P., suggesting that it was deposited before the earlier Aso-2 and & -3 eruptions and has been drowned in the groundwater at least three times. Many speleothems are submerged for a period longer than over 85,000 years, and therefore the groundwater had been nearly at dissolution equilibrium with respect to calcite due to slow water circulation. However, undersaturation with calcite dissolution has sometimes happened to the groundwater after the cave was opened for public in 1976 by artificial lowering of the water level by about 4 m.

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Iron isotope compositions were measured for various types of carbonate rocks through the history of the Earth. I found that 3.0-Gyr-old stromatolite has the most significant Fe isotope fractionation, suggesting the operation of extensive Fe redox cycling by mat-forming microbes since at least the middle Archean.

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