Distribution of chlorobenzenes (CBs) was surveyed in the surface seawater of Ise Bay in Japan. The dissolved CBs and the adsorbed CBs on suspended particulates were monitored at 40 stations throughout the bay area. The dissolved CB levels in filtered seawater were high in an area from Yokkaichi on the west end of the bay toward Tokoname on the east coast in the cases of dichlorobenzenes (DCBs), trichlorobenzenes (TCBs) and tetrachlorobenzenes. These data showed that the pollutants discharged near Yokkaichi Port were carried in the surface water by the stream caused by the Kiso, Ibi and Nagara rivers. The adsorbed CB levels on the suspended particulates did not show any particular distribution pattern in the bay and their correlations with the dissolved levels were low. The partition coefficients based on the organic carbon contents (log K_oc) for DCBs and TCBs were low in the area from Yokkaichi to the front of Tokoname and high just outside of this area. These phenomena could be interpreted as follows: the relatively undiluted polluted plume with a higher dissolved concentration and lower log K_oc value was located in the surface of the area from Yokkaichi to the front of Tokoname. Also, just outside of this plume, the dissolved levels decreased rapidly due to the diffusion while the adsorbed CBs did not desorb from the particulates as fast as the decrease in the dissolved CBs in the surrounding water.
In spite of the relatively large site dependent variation of log K_oc in the bay, the log K_oc values averaged over certain bay area for each CB isomer correlated well with the octanol/water partition coefficient (log K_ow) reported for those compounds. These showed that property of the compounds, namely log K_ow, was the major controlling factor of log K_oc in the field and observed relatively large variation of log K_oc was probably due to the slow desorption of CBs from particulates.

View full abstract

As a part of study to evaluation of mutagenicity of air pollutants, a mutagenicity detection method for volatile compounds was examined. The umu test procedure employing Salmonella typhimurium TA1535/pSK1002 strain was used in this exposure test system. The trapping bacterial solution in three impinging tubes were exposed to typical volatile mutagens.
The mutagenicities of propylene imine and benzotrichloride were clearly recognized with the assay system. It was also found that the mutagenicity of hydrophobic compounds, such as benzotrichloride, could be estimated according to this plural impinging method.

View full abstract

The past pollution by dioxins in south Vietnam was studied by analyzing soil and sediment core samples. TCDD was not found from these samples in spite of the large use of defoliant during the Vietnam War. On the other hand, highly chlorinated dioxins were detected from almost all samples analyzed. The levels ranged from 0.069 to 1.1 ng/g dry weight basis, and their isomer compositions which contained about 80%, 15% and 5%respectively for OctaCDD, HeptaCDDs and HexaCDDs. Isomer patterns were very similar each other. The isomer composition is similar to that found in deep core layer of sediment collected from Japanese coastal areas suggesting the presence of “natural dioxins”.

View full abstract

Gas chromatographic method has been developed for determination of nitro polycyclic aromatic hydrocarbons (nitro-PAHs) in automobile exhaust.
Nitro-PAHs are determined by gas chromatography (GC) using a flexible fused silica capillary column and splitless injection with a surface ionization detector (SID), which is a sensitive and selective detector for GC.
It has been shown that the GC in combination with SID provides a selective and sensitive method for determination of nitro-PAHs in diesel exhaust particulates after the HPLC fractionation as a pre-treatment.

View full abstract

Variations of four pesticide concentrations in the atmosphere were investigated after aerial applications to paddy fields located near urban sites. The pesticides investigated were 2-chloro-1- (2, 4, 5-trichlorophenyl) vinyl dimethyl phosphate (tetrachlorvinphos), o-sec-butylphenyl methylcarbamate (fenobucarb), S-1, 2-bis (ethoxycarbonyl) ethyl O, O-dimethyl phosphorodithioate (malathion) and O, O-dimethyl O-4-nitro-m-tolyl phosphrothioate (fenitrothion) .
In the applied area, maximal concentrations of tetrachlorvinphos, fenitrothion, fenobucarb and malathion were 1.8μg·m^-3, 11μg·m^-3, 18μg·m^-3 and 2.4μg·m^-3, respectively. The concentrations of the pesticides were<0.01μg·m^-3 on 5 days after the application at the almost sampling sites. The concentrations in the applied area were mainly dependent on vapor pressure, air temperature, passing time after the application and wind speed. These pesticides were drifted to the points located 45-750m from the applied area. The pesticide concentrations in these sites were 0.02-9.3μg·m^-3 at maximum, and were mainly dependent on the distance from the applied area, air temperature, passing time after the application, and the concentration in the applied area.

View full abstract

Lanthanum alizarin complexone photometric method using an HPLC with post column was investigated for the detrmination of flouride ion in environmental samples.
Instrumental conditions are listed as follows : column ; Shimpac IC-1A (5.0mm i.d. × 100mm), eluent ; 2.5mM phtharic acids +2.4mM Tris (hydroxymethyl) aminomethane, flow rate 1.0ml / min. detector; conductive (CDD-6A) and spectorophotometric detector UV-BIS (SPD-10A) .
Detection limit by the method was at 0.001ppm. Fluoride ion in tap, rain, sea, lake and river water samples was determined at ppb level by the method.

View full abstract

Recent studies on polychloronaphthalenes are focused on the strongly bioaccumulating isomers of hexachloronaphthalenes (HxCN), i. e. 1, 2, 3, 4, 6, 7-and 1, 2, 3, 5, 6, 7-HxCN. However, not all of HxCN isomers are identified yet. In this study, three of the four unidentified HxCN isomers are synthesized as follows:
1, 2, 3, 4, 5, 8-HxCN was obtained by heating 2, 3-dichloro-5, 8-dihydroxy-1, 4-naphthoquinone with phosphorous pentachloride. 1, 2, 3, 4, 5, 7-HxCN was obtained by chlorination of 1, 2, 3, 4-tetrachloronaphthalene together with three separable isomers. 1, 2, 3, 5, 6, 8-HxCN was obtained by heating 2, 5, 6, 7-tetrachloro-1, 4-naphthoquinone, which was derived from 1, 2, 3, 6-tetrachloronaphthalene. All peaks of HxCN in Halowax 1014 and municipal fly ash samples were identified and the strongly bioaccumulating HxCNs were dominant isomers in most of the fly ash samples.

View full abstract

Various surface soil in ten locations where kosa aerosol are originated were characterized for carbonate carbon and other elements. Surface soil samples were separated for 0.43-1.1, 1.1-11, 11-240 and over 240 μm in aero-dynamic diameter size. The weight percent of 1.1-11μm fraction in loess samples gave about 1-3%, and those in desert sand samples also gave less than 1%. Carbonate carbon in both loess and sand samples was accumulated abundantly in small particle fraction less than 11μm, and these carbonate carbon were revealed to derive from calcite (CaCO₃) mineral. Chloride, nitrate and sulfate as well as carbonate were found to accumulate as particle size is smaller, on the other hand, the crustal enrichment factors (based on Al) for Ca, Mg, Sr and Na such as alkaline element were smaller.

View full abstract

Since Japanese environmental law for natural water quality was largely amended in 1993, ICP-AES analysis becomes to be more useful as one of the official regulated method for many trace elements in the environmental water samples. The upper limit concentration for some elements in this amended law were changed10 times more stringent than in the previous law, as given an example for lead (0.01mg/l) . Therefore, ICP-AES analysis with an ultra-sonic nebulizer is recomended in order to examine whether lead concentration in a sample is over against the amended law. An ICP-AES analytical technique with an ultra-sonic nebulizer gave the detection limit at 1μg/l level for lead, and this value was several times more sensitive than that with a conventional nebulizer. But also, spectroscopic interferences, which are always occurred on ICP analyses for severe samples by matrix effects, were found to be heavily given by an ultra-sonic nebulizer.

View full abstract

Recent studies on biodegradation and risk assessment of microcystins are introduced. On the biodegradation of microcystins, G. J. Jones and P. T. Orr suggested that the initial bacterial transformation of microcystin resulted in a product more inhibitory to protein phosphatase than the parent toxin. On the risk assessment, I. R. Falconer et al. described the use of growing pigs as a model for human injury resulting from Microcystis toxins (microcystins) in drinking water. Risk assessment calculations using a series of safety factors were carried out, resulting in a guideline level after incorporating an additional safety factor for tumor promotion of approximately 1.0μg toxins / L.
These results are very important in problems of toxic waterblooms occurred in drinking water supplies.

View full abstract

Studies on collection of polynuclear aromatic hydrocarbons (PAHs) in air with denuder tubes are introduced. Vaper-particle partition of PAHs in air has been measured by using the denuder/filter/polyurethane-foam systems.

View full abstract