Only about half of all the CO₂ that has been produced by the burning of fossil fuels now remains in the atmosphere. The CO₂ missing from the atmosphere is the subject of an important debate. One of the great possibility of the missing CO₂ is to know the pool and turn-over time of oceanic organic carbon, especially dissolved organic carbon in the carbon cycle. Measurement of dissolved organic carbon in seawater has been much argued for a long time. An essential discussion is described in relation to the understanding “Nature”.

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We developed a capillary column gas chromatography/mass spectrometric method for the determination of nereistoxin and thiocyclam in environmental samples as river water, sea water, sea sediment and fish meat. Nereistoxin and thiocyclam in the samples were extracted by liquid-liquid extraction using dichloromethane.
The detection limit of nereistoxin and thiocyclam in water, sediment and fish meat were 0.13 and 0.09μg/L, 3.3 and 4.8μg/kg, and 3.3 and 4.1μg/kg, respectively. The recoveries of nereistoxin and thiocyclam from river and sea water samples were more than 86%, while those from sediment samples were about 50%. From the results of the stability test of the compounds in the sediment, it was suggested that these low recoveries were due to decomposition and polymerization of the compounds.

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3, 3', 4, 4'-tetrachlorobiphenyl (3, 3', 4, 4'-TCB), 3, 3', 4, 4', 5-pentachlorobiphenyl (3, 3', 4, 4', 5-PeCB) and 3, 3', 4, 4', 5, 5'-hexachlorobiphenyl (3, 3', 4, 4', 5, 5'-HxCB) were measured in air samples collected at several points in Fukuoka prefecture in 1990 and 1992 using a high volume air sampling method. The concentrations of 3, 3', 4, 4'-TCB, 3, 3', 4, 4', 5-PeCB and 3, 3', 4, 4', 5, 5'-HxCB in 1990 were N.D. (<0.01) -2.03, 0.04-0.63 and 0.02-0.42 pg/m³, respectively, and 0.07-2.3, 0.01-0.51 and N.D. (<0.01) -0.18 pg / m³ in 1992, respectively. The concentrations of non-ortho coplanar PCBs in 1992 were identical with those observed in 1990. Similar seasonal differences were both observed for congeners of non-ortho coplanar PCBs in 1990 and 1992. The concentrations of 3, 3', 4, 4'-TCB were higher in summer than winter while those of 3, 3', 4, 4', 5-PeCB and 3, 3', 4, 4', 5, 5'-HxCB were relatively higher in winter. The non-ortho coplanar PCBs concentrations observed in 1992 from sites sampled in 1990 were relatively close to the 1990 values. 3, 3', 4, 4', 5-PeCB and 3, 3', 4, 4', 5, 5'-HxCB were found to correlate with each other, but not with 3, 3', 4, 4'-TCB. The 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin toxic equivalent (TEQ) levels of non-ortho coplanar PCBs were 0.005-0.086pg (TEQ) / m³ in 1990, and 0.002-0.074 pg (TEQ) / m³ in 1992, respectively. 3, 3', 4, 4', 5-PeCB was identified the dominant congener of non-ortho coplanar PCBs, providing 62% of the TEQ loading.

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Since the utilization of underground space have been recently increased, air pollution and human exposure to the pollutants in the space have been apprehended. Therefore, airborn PAHs, which are major carcinogenic / mutagenic substances in air were measured at four underground space / shopping mall of terminal stations in metropolitan area.
It was capable to measure the concentration of Pyrene, BaA, BkF and BaP in underground air sample, which was collected by a personal mini pump (flow rate; 1.01/min, for lhour), by using a column concentration HPLC / fluorometric detection method. The sampling method was suitable for the survay. The sampler was oparated without the standing electric source, light weight and silent. Loss of volatile PAHs and artifact formation during sampling was minimized by short sampling time and small sampling volume.
Compared to the corresponding outside air, extreme pollution was not found, but some higher PAH concentrations were observed.

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Capillary Ion Analysis (CIA) is one of new technologies in Capillary Electrophoresis (CE) . CIA methods are applied for analysis of inorganic anions / cations, organic acids and amino acids in hot water extractives of Garbage Automatic Decompose Extinguisher (GADS) samples which are complex mixtures containing many kind of other compounds. The advantages of CIA methods compared with current technologies are speed, simplicity, and high resolution with minimal reagent consumption. The quantitative and qualitative analysis of GADE samples by CIA methods reveal that accumulation of high concentration minerals with a small amounts of organic and amino acids in sawdust after GADE treatment. These results suggest that LADE system completely decomposes the garbage without occurrence of any bad smell and the final products are converted into artificial compost.

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A determination method of phenols in water samples was developed. To optimize the conditions for direct acetylation of 16 phenols, absolute recoveries were measured. Alkylphenols, chlorophenols and nitrophenols were acetylated almost quantitatively with acetic anhydride using K₂CO₃ as base. Then, acetyl derivatives formed were quantitatively extracted with dichloromethane.
Linear working curves through the origin were obtained in the concentration range 0.05 to 5μg / L except nitrophenols.

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Contamination levels and its distribution of volatile chlorinated organic compounds, that is, trichloroethylene (TCE), tetrachloroethylene (PCE), 1, 1, 1-trichloroethane (MC), 1, 1-dichloroethylene (1, 1-DCE), cis-1, 2-dichloroethylene (cis-1, 2-DCE), and trans-1, 2-dichloroethylene (trans-1, 2-DCE) in 494 well waters in Tama District in Tokyo were measured from April 1991 to March 1992. These waters were classified into shallow well water draw from non-confined groundwater (N=267) and deep well water draw from confined groundwater (N=227) .
The cause of contamination of 1, 1-DCE or cis-1, 2-DCE was investigated by statistical analysis of the results from this monitoring.
Detection rate and maximum levels of the compounds were 50% and 280μg/l for TCE, 31% and 513μg/l for PCE, 42% and 466μg/l for MC, 41% and 22.1 μ/l for 1, 1-DCE, 21% and 118μg/l for cis-1, 2-DCE, respectively. traps-1, 2-DCE was detected only from one shallow well water at 1μg/l. Detection limits were set at 0.1μg/l for 1, 1-DCE and at 1μg/l for other compounds.
The present contamination levels of TCE, PCE and MC were compared with those in 1986. For 44 shallow well waters, the contamination levels of TCE did not change, and those of PCE and MC increased. For 43 deep well waters, the levels of TCE decreased and those of PCE and MC did not change.
Contamination levels of 1, 1-DCE correlate to those of TCE and MC, and contamination levels of cis-1, 2-DCE correlate to those of TCE and PCE. From these results, the contamination of 1, 1-DCE and cis-1, 2-DCE in groundwater was regarded as transformations of TCE, PCE and MC in the environment in Tama District in Tokyo.

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