Some styrene degradable strains at around pH 7 were screened. Among them one candidate strain of styrene degrader, Pseudomonas sp. No. 14, was selected at low pH. In sealed flask batch experiment, specific styrene uptake rates of the strain No.14 at pH 5.5 and 7.0 were 1.95t×10^-8μmol/h/cell and 1.81×10^-8μmol/h/cell, respectively When the strain No.14 was applied to styrene biofilter, complete removal capacity at pH 7 was inferior to Peudomonas sp. SR-5, a high-strength-styrene degrader, but at low pH 3.0, where strain SR-5 lost styrene removal ability, the strain No.14 maintained high styrene removal capacity of 150g/m³/h. The strain No.14 will be applicable to high load styrene biofilter, because frequent neutralization is not needed which occurred due to accumulation of styrene metabolites at high styrene loading on biofilter

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We propose a convenient method of preparing samples of solid and slurry materials for odor measurement. Odor indices of cow excreta, compost, and liquid residue (liquid manure) sampled from cow barns and also from composting and biogasification facilities treating cow excreta were measured by the triangle odor bag method after preparation using our method.
The odor indices (X) of cow excreta were in the range 24-35. The odor indices of compost and liquid manure (Y) were about 20-25, lower than the odor indices of cow excreta. The differences of the odor indices were in the range 3-11. By this method, the degree of reduction in odor by composting and biogasification of cow excreta was shown quantitatively.

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We examined the effects of cognition on the hedonics of three typical offensive odor pollutants. One hundred fifty-four healthy women and men were exposed to one of three odors (ethyl acetate, hydrogen sulfide, or ammonia), which are regulated as odor pollutants in Japan, after being told that the odorant was healthful, neutral, or harmful. Participants continuously rated the odor intensity for 10min using a slide lever. A measurement system for odor adaptation controlled the concentration and duration of the presented odor, and recorded the intensity of the responses every 50ms. After the presentation of the odorant, the participants ranked the hedonics (pleasantness-unpleasantness) of the odor using a visual analog scale from -100 (very unpleasant) to +100 (very pleasant).
The results revealed the effects of cognition on the hedonics of offensive odorants. These effects, however, were different for the three odor pollutants ; the largest effects were observed with ethyl acetate, whereas the smallest effects were observed with ammonia. These results should help to address problems associated with individual differences in the regulation of odor pollution.

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In order to make clear the characteristics of odorant adsorption by different types of activated carbon, three series of pilot-scale deodorization tests were conducted at a wastewater treatment plant. Activated carbons used were impregnated ones specified for acidic gases (e.g. hydrogen sulfide, methyl mercaptan, etc.), neutral gases (e.g. dimethyl sulfide, dimethyl disulfide, etc.) and basic gases (e.g. ammonia, etc.) and a non-impregnated one. Three PVC adsorption columns using a three-stage packed bed system were prepared for these tests. Each column was about 1.5m in height and 280mm in diameter. The design capacity of each column is 0.75m³/min. Odorous gas containing hydrogen sulfide at approximately 10ppm was continuously fed to three columns at a linear velocity of about 0.2m/s. The term of each test was about 100 days and odor measurement was usually carried out once a week.
Data related to odor removal efficiency could be obtained for 9 different combinations of packed carbon types. From these results, total loading of odorants fed to the column till break-through was calculated for each impregnated activated carbon. Obtained value of adsorption capacity was lower than that of laboratory testing. It was thought that decrease of adsorption capacity in field testing was caused by many kinds of odorants contained in the inlet gas of the adsorption columns. Ammonia contained in the inlet gas heightened the value of H₂S adsorption capacity for acidic gas-impregnated carbon ; however it caused corrosion due to reaction with impregnated chemicals for neutral gas-impregnated carbon. It was considered that the results of these pilot-tests would give us much useful information for the design planning and maintenance of odor adsorption facility.

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