Residue of PCB, DDT and HCH in fish from lakes and rivers in the world was reviewed from the surveys in the years of 1995-2007. PCB and T-DDT concentrations in the fish from the lakes and rivers of America were relatively high, but those of Europe, Asia and Africa were relatively low. T-HCH concentrations in the fish were relatively low in both of the lakes and rivers in all the world. DDT was presumed to be used in Egypt, Tanzania and Brazil from the high percentage of pp’-DDT in the composition of T-DDT in the several kinds of fish from Lake Burullus, Lake Victoria and Ponta Grossa Lake. Technical HCH was presumed to be used in Japan, China and India from the low percentage of γ-HCH in the composition of T-HCH in the lake and the river fish in the countries. On the contrary, Lindane was presumed to be used in the countries of Europe and Africa from the high percentage of γ-HCH in the lake and the river fish in the countries. Half-lives (t_1/2) of PCB and T-DDT in fish from lakes in Japan, USA and Sweden were calculated from the long-term monitoring data using an exponential decay model. The t_1/2 values were 20years in Lake Biwa, 10years in Lake Ontario, 7years in Lake Michigan and 20years in Lake Storvindeln for PCB and 9years in Lake Biwa, 10years in Lake Ontario, 8years in Lake Michigan and 7years in Lake Storvindeln for T-DDT.

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Secondary emission products generated through chemical reactions become a recent concern in relation to indoor air quality. We have focused on formic acid (HCOOH) whose generation mechanism in indoor air has been unknown. In this study, we examined influence of oxidant on the indoor air concentrations of HCOOH and emission process of HCOOH by both laboratory experiments and field measurements. Firstly, emission fluxes of HCHO and HCOOH from plywood were determined using a small bowl-type stainless chamber. The emission flux of HCOOH increased with those of HCHO under ambient air containing oxidant. While the oxidant was removed in the chamber, HCOOH significantly emitted with NO₂ at the chamber outlet. We then concluded HCOOH is a product of the gas phase reaction between HCHO, NO₂ and O₃. Field measurements conducted at a newly-build detached house supported the conclusion as that indoor concentrations of HCOOH increased with an increase in concentrations of the oxidant introduced from outdoor by air ventilation.

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Amberlite XAD-2 resin extracts of river and drinking water sampled each month during the period from January to December 2008 from Northwest Area of Chiba Prefecture were investigated in order to characterize and determine the organic pollutants. On the basis of GC/FID determinations of the extracts, over 90% of XAD extractable organic substances present in the river water concentrates was found to be reduced after processing in water treatment plant. Personal care products (DEET and Crotamiton) were also identified by GC/MS to be present at low concentrations, ranging from ND to 140 ng/L. The concentrations of these organic pollutants were dependent on the application periods. Although amounts of these organic pollutants in river water samples decreased remarkably after processing in the water treatment plant, it is necessary to conduct continuous bio-assays in order to evaluate the health risk effects of these personal care products and their chlorination byproducts in drinking water.

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The present study demonstrates the seasonal variations of concentrations of pharmaceutical and personal care products(PPCPs) in influents and effluents at two sewage treatment plants (STPs) and the surface water of Mankyung River, South Korea. PPCPs were measured using a high performance liquid chromatograph coupled with a tandem mass spectrometer(LC-MS/MS). In the two STPs surveyed, all of the 13 targeted PPCPs were detected at concentrations ranging from ND (not detected) to 13700 ng/L in the influents, and ND to 1940 ng/L in the effluents, with total PPCP concentrations being higher in winter than in other seasons in both STP influents and effluents. While the removal efficiencies of disopyramide, ibuprofen, triclosan, erythromycin, atenolol and indomethacin of the STPs were relatively high (average 60-90%), those of clarithromycin, carbamazepine, fluconazole, propranolol and ifenprodil were extremely low (average 0-30%).The prevalent contaminants in the river water in all seasons were carbamazepine (ND to 595 ng/L), followed by atenolol (ND-690 ng/L), ibuprofen (ND-414 ng/L), mefenamic acid (ND-326 ng/L), levofloxacin (ND-380 ng/L), clarithromycin(ND-443 ng/L), fluconazole (ND-111 ng/L), erythromycin (ND-152 ng/L), propranolol (ND-268 ng/L), ifenprodil (ND-38.5 ng/L), indomethacin (ND-58.2 ng/L), triclosan (ND-46.1 ng/L) and disopyramide (ND). Concentrations of PPCPs in surface river water collected from five sample sites trended to be higher in November than in March, May and August. It was proposed that the reasons for the observed seasonal variations in PPCP concentrations may be increased consumption by the inhabitants of the Mankyung River basin and the decreased river flow during this period leading to increased relative concentrations of these compounds in water. In addition, PPCP concentrations were greater in the surface water samples collected in the vicinity of STPs, so STPs act as a point source of PPCP pollution.

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Polycyclic aromatic hydrocarbons (PAHs) concentrations in the bivalves were measured to elucidate the background levels of PAHs in the coastal waters of Japan. Seven species of bivalves, mainly Mytilus galloprovincialis and Septifer virgatus were collected in 64 sites. Eighteen kinds of PAHs having two to six rings were analyzed in 137 samples.
The range and median of ΣPAHs concentrations were 1.6-140 ng/g wet wt and 19 ng/g wet wt, respectively. There were no significant differences in the ΣPAHs concentrations among species. The high ΣPAHs concentrations sites were mainly observed in the Pacific coast of the south of Kanto region and around the Inland Sea.
Two concentration ratios (methylphenanthrene/phenanthrene and 4,5-methylenephenanthrene/methylphenanthrene) were examined in order to identify PAHs sources. Those results suggested the source of PAHs was mainly from combustion. And the sites where the influence of oil spill had been expected were observed in the coasts of Chugoku, Shikoku, and Kyushu regions.

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In this study, we examined the removal and decomposition efficiencies of regenerated amorphous iron oxide on tributyltin (TBT) and triphenyltin (TPT). The results indicated that removal capacity could be estimated from Freundlich function, and also that half-life period of TPT by contact with the iron oxide at 20 °C was 3.1 hours, which was from one hundredth to one tenth in comparison with natural environment condition. Furthermore, the romoval rate of TBT and TPT on the treatment of high polluted sea water made from actual polluted sediment were 80% and 97% respectively. These observations indicate that this iron oxide is useful for treatment of organotin compounds in seawater.

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The adsorption mechanisms of nitrate ion on chemically and physically treated activated carbon (AC) were investigated. The commercial activated carbon (NORIT R1 EXTRA) was first de-ashed with both acids of HCl and H₂F₂. The de-ashed AC was then treated with nitric acid to introduce acidic functional groups on the surface, subsequently outgassed at different temperatures of 600, 800 and 1000 °C in helium flow to eliminate acidic functional groups. Also, the out-gassing treatment at different temperatures of 500, 700 and 1000 °C was conducted for the de-ashed AC to increase Cπ electon site on the graphene layer. The results obtained in this study showed that the introduction of acidic functional groups on the surface of AC could be achieved through acid treatment with nitric acid. Carboxylic and lactonic groups could be completely removed by out-gassing under the temperature over 800 °C. Also, Cπ electron site was increased accompanying to higher temperature in the process of out-gassing. The surface acidic functional groups such as carboxylic and lactonic groups prevented the adsorption of nitrate ion, while no interruption for the adsorption of nitrate ion by phenolic hydroxyl group was observed contrastive to carboxylic and lactonic groups. The amount of nitrate ion adsorbed on the carbon could be increased with the expansion of basic site.

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We developed for accurate measuring method of mono-hydroxyl polychlorinated biphenyls (HO-PCBs) which has 839 of ideal congeners by coupling comprehensive gas-chromatograph (GC×GC) and high resolution time-of flight mass spectrometer (HRTOFMS). One hundred and nineteen of HO-PCB standard isomers were measured to determine the retention time on the two-dimensional chromatograms of GC×GC-HRTOFMS and then the method was applied to river sediment samples.
Under optimized condition of the GC×GC-HRTOFMS equipped a 5%-phenyl/methyl silicorn (as 1st column) and a 50%-phenyl/methyl silicorn capillary column (as 1st column), 111 peaks were obtained on the two-dimensional chromatogram. Only 5% of peak separation was improved against generic a GC.
One hundred and fifty two peaks derived from HO-PCBs in river sediment were detected by the GC×GC-HRTOFMS although 125 peaks detected by single GC mode. Methyl derivatized HO-PCB was, however, not identified in major peaks on the chromatograms of the GC×GC-HRTOFMS because of inefficient sensitivity of the detector and foreign substances.
To more utilize this method, it is necessary to improve sensitivity and dynamic range of detector on a TOFMS and develop a new software allows easy quantification and identification on data of a GC×GC-HRTOFMS.

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A determination method of atmospheric oxygenated polycyclic aromatic hydrocarbons (Oxy-PAHs) in particulate matter and the gaseous phase using gas chromatograph (GC)-mass spectrometer (MS) was studied in the present study. First, we obtained fundamental data of GC-MS analyses (mass spectra and calibration curves) of twelve Oxy-PAHs as follows: acenaphthenequinone (AceQ), 1,4-naphtoquinone (1,4-NQ), 9-fluorenone (9-F-one), 1,4-phenanthrenequinone (1,4-PQ), 1,4-, 9,10-anthaquinone (1,4-, 9,10-AQ), 1-hydroxyanthrquinone (1-OHAQ), 1,2-benzanthraquinone (1,2-BAQ), benz[c]phenanthrene[1,4]quinine (BcP-1,4Q), 3,4-dihydrobenzo[a]anthracene-1(2H)-one (BaA-one), 1,4-chrysenequinone (1,4-CQ) and 9,10-dihydrobenzo[a]pyrene-7(8H)-one (BaP-one). Subsequently, to evaluate collection efficiency of Oxy-PAHs, air was passed through a quartz-fiber filter (QFF) spiked with authentic Oxy-PAHs and then through cleaned polyurethane form (PUF) plugs using a mini-pump or a low-volume air sampler for 24 h in the dark at a constant room temperature (20 or 35 °C). Oxy-PAHs retained on the QFF and those trapped within PUF plugs were simultaneously Soxhlet extracted, purified with silica by gel column chromatography and determined using GC-MS.
The calibration curves for the determination of the twelve Oxy-PAHs were proportional in the concentration range between 0.02 and 1.0 μg/mL with r² values of 0.960-0.999. Among the twelve Oxy-PAH compounds examined, recoveries of six compounds (1,4-NQ, 9-F-one, 9,10-AQ, 1,2-BAQ, BaA-one and BaP-one) during sampling, Soxhlet-extraction and clean-up procedures sufficiently yielded 79-127% at a room temperature of 20 °C and 57-127% at 35 °C . The method detection limits (MDLs) of the six compounds ranged between 0.61-1.07 ng/m³.
The proposed method was applied to the determination of the six Oxy-PAH compounds in the atmosphere. Air sample was collected at an urban location of Osaka, Japan for 12-13 February 2007. 1,4-NQ, 9-F-one and 9-F-one were detected in the sample at concentration level of approximately 0.7-3 ng/m³.

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