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Investigation by the column method of removal of heavy metals from plating factory wastewater with economical materials is done. This method is highly effective as removal efficiency tended to increase with increasing pH and decrease with increasing metal concentration.

Abstract: Biocides have been used not only in everyday items such as clothes, kitchenware, daily necessities, and infant utensils, but also in cosmetics and wrapping papers for foodstuffs. Since there is a high possibility of exposure to biocides from such materials, their safety must be assessed adequately using a range of methods. We investigated the estrogenic activity of 20 organic biocides using two in vitro screen assays: estrogen receptor (ER) binding assay and yeast estrogen screen (YES) assay. Twelve of the biocides were positive in the ER-binding assay. Regardless of the presence or absence of rat S9Mix for metabolic activation, 4-chloro-3-methylphenol was positive in both ER-binding and YES assay. 4-Chloro-3,5-dimethylphenol was positive in the ER-binding assay and showed a pseudopositive manner in the YES assay that was observed the dose-independent estrogenic activity at only one dose point. Hiba oil was positive in the ER-binding assay but was positive in the YES assay only in the presence of rat S9Mix. These results suggest that ER-binding and YES assay could be adapted for evaluation of the endocrine-disrupting activity of biocides. The biocides found to be positive in vitro now require assessment by in vivo screening methods. [Copyright &y& Elsevier]

Concentrations of particulate matter (PM) and carbonaceous particulates in indoor and outdoor air at roadside private households were measured in Osaka, Japan. The particulate samples were collected on filters using a portable AND sampler capable of separating particles intothree different size ranges: over 10 mu m, 2-10 mu m (coarse) and below 2 mu m (fine) in aerodynamic diameter. The filters were weighed and then analyzed for elemental carbon (EC) and organic carbon (OC) bythermal oxidation using a CHN CORDER. The results showed that indoorfine PM concentration is considerably affected by fine EC and the fine EC in indoor air is significantly correlated to that in outdoor air, r=0.86 (n=30, p<0.001). A simple estimation from EC content ratio in diesel exhaust particles indicated that about 30% of indoor particulates of less than 10 mu m (PM10) were contributed from diesel exhaust. Additionally, the size characteristics of outdoor PM at roadside and background sites were examined using Andersen Cascade Impactors. [ABSTRACT FROM AUTHOR]

Atmospheric particulates were monitored on a typical high concentration day in early winter in Osaka, Japan, using a compact and portableeye-safe laser radar system. The height of mixing layer was about 0.4 km at 8:00 and gradually increased to 0.8 km at 14:00. The development of the layer was in inverse proportion to the decrease of particulates near the ground surface. Analysis of particulates collected with high-volume air samplers showed that concentrations of elemental carbon (EC), lead and ammonium ion near the surface decreased significantly from morning to midday, while concentrations of sulfate, nitrate, sodium and calcium ions were almost constant. The results obtained in the preliminary study suggest that anthropogenic particulates suchas EC and lead are on the rise with development of mixing layer frommorning to midday. [ABSTRACT FROM AUTHOR]

Characteristics of air pollutants in a highway tunnel were studied in Osaka, Japan. The size distributions and concentrations of elemental carbon (EC) and organic carbon (OC) were measured. The results demonstrated that EC was the predominant constituent of particulates in the tunnel, which accounted for 71% by mass of the particulate matter (PM) of less than 2 mum in aerodynamic diameter. EC concentration increased linearly with increase in diesel traffic volume and the coefficient of correlation was found to be at a significant level (r=0.93, p<0.001). In contrast, OC size distribution was bimodal with peaks inthe size ranges of less than 1 and 2-10 mum and not clearly dependent on diesel traffic volume. For the gaseous matter, nitrogen monoxide(NO) was found to be the major component of NOx (over 90%) and its concentration was proportional to the traffic volume of diesel vehicles (r=0.82, p<0.001). The concentrations of carbon monoxide(CO) and carbon dioxide (CO2) in the tunnel were found, by multi-regression analysis, to be dependent on both diesel and gasoline-powered vehicles. [ABSTRACT FROM AUTHOR]