From the ultraviolet irradiation test of modified auto-exhaust gas, the relation between O_3max and initial non-methane hydrocarbon (NMHC), nitrogen oxides (NO_x) concentrations was analyzed by multiple regression analysis. Multiple correlation coefficients of multiple regression formula, in which O_{3 max} was critorion variable and the concentrations of NMHC, NO_x were predictor variables, denoted good significance at significant level of 0.01 or 0.05, it became apparent that 0_{3 max} related to [NMHC] ₀ and (NO_x) ₀. By the comparison of standardized partial regrossion coefficients, it was clarified that 0_{3 max} was greatly affected by NMHC in [NMHC] ₀/[NO_x] ₀ ratio 4-15, and also was greatly affected by NO_xin [NMHC] ₀/[NO_x] ₀ ratio 15-46.

View full abstract

Ambient air monitoring stations are allocated in consideration of source situations, meteorological conditions and terrain. However, as the criterion of the assessment for the allocation of stations has never established, it is an urgent problem to develop the method which can assess quantitatively the allocation.
The purpose of this study is to assess the allocation of stations comprehensively and quantitatively by applying multiattribute utility function method.
First, the structure model of the criteria is defined in order to assess the allocation of stations not only from the technical point of view but also from the economic point of view.
Secondly, interview examinations are enforced for the researchers and the officers who are working in air pol-lution field, then individual value systems are clarified, and individual multiattribute utility functions is derived.
Thirdly, the allocations of ambient air monitoring stations are assessed quantitatively based on the derived multiattribute utility function.
As the result of this approach, it has been confirmed that the value systems between the researchers and the officers are different and the allocation of stations can assess comprehensively and quantitatively.

View full abstract

Proposed several methods of graphic display to extract the characteristics of periodic movements of atmospheric monitoring data.
Some visual patterns can be recognized by use of the appropriate matrix construction of the data on a picture.
The data are divided into several levels by the thresholds such as the environmental quality standards or the percentiles (75 percentile and 90 percentile are recommended). And those levels are assigned to the gray scales or the adequate color codes.
In a matrix for the display of one month data, “hour” is selected as a column, and “day” or “day of the week” is selected as a row. Displaying the matrix, some features of periodic movement of hourly averages, for examples, of oxidant and nitrogen oxides concentration were recognized. Using a similar method, the relation of the simultaneous movements of two kinds of pollutants such as NO and NO2 could be obtained synoptically on a color graphic display. The characteristics of the data of a pollutant in a year, and the features of the occurrences of missing data are also obtained by constructing the appropriate matrices on a display.
An architecture of the computer system for the graphic display by these methods is also represented.

View full abstract

In order to evaluate temporal variation of spatial distribution patterns of NO₂ concentration, daily average concentration was measured by diffusion samplers at every 1 km2 mesh in an area of about 30 km² in the suburbs of Tokyo. Survey was carried out over 7 days each in April and in December of 1984. Analysis of variance of a 2 way classification, whose criteria are days and sampling points, shows;
(1) Variance between days (D) is extremely large. Spatial averages vary markedly day by day, reflecting human activities and meteorological conditions, especially wind speed.
(2) Variance between sampling points (P) is large in comparison with variance due to P×D interaction terms. Features of spatial distribution pattern that NO₂ concentration is high around the crossings of principal roads are common to all days.
(3) Spatial distribution pattern varies somewhat according to the prevailing wind direction of the day. Variance within group is reduced to the same order of magnitude as variance of measurement error when variance due to P×D interaction is partitioned by wind directions.

View full abstract

We examined the distributions of s-hr averaged concentrations by δ₂-δ₃ diagram test and derived the following results:
(1) The distribution of s-hr averaged concentrations is the same as the hourly distribution at most of the monitoring stations.
(2) The Point (δ₂, δ₃) moves straightly to origin as increasing averaging time on δ₂-δ₃ diagram.
From these results, we propose the new arrowhead chart model which fit the observed data better than any other model when air pollutant concentrations are approximated to Pearson distributions. This model is numerically expressed as follows:
μ₁'(s)=μ₁'(1)
δ₂ (s)=δ₂ (1) G (s)/G (1)
δ₃ (s)=δ₃ (1) G (s)/G (1),
where μ₁'(1), μ₁'(s): means of hourly concentrations and s-hr averaged concentrations respectively,
δ₂(1), δ₂(s): variance coefficicnts of hourly concentrations and s-hr averaged concentrations respectively,
δ₃ (1), δ₃ (s): skewness coefficients of hourly concentrations and s-hr averaged concentrations respectively,
G (s) =2/s∫s0 (1-τ/s)γ(τ) dτ, γ(τ): auto-correlation coefficient.
Using this arrowhcad chart modcl, we investigate the method of estimating δ₂ (1) and δ₃ (1) from δ₂ (s) and δ₃ (s) when auto-correlation coefficient is approximated to exponential curve or exponential curve plus sine wave.

View full abstract

The umu-test is based on measuring the activity of j9-galactosidase induced as a SOS-response against DNAdamaging agents (≅carcinogens and mutagens) in Salmonella typhimurium TA1535/pSK1002. The test system is very useful for detecting and monitoring the carcinogens and the mutagens in air, because it is simple, rapid and inexpensive. However, the conventional umu-test has some problems on measuring the colored sample, such as airborne particulate extract, and on the sensitivity. The present authors have developed an improved method as follows:
1) For the improvement of accuracy, test mixture without enzymatic reaction was used as a reference solution for the measurement of UV-absorbance in β-galactosidase activity assay. 2) Reincubation of the diluted overnight culture, which was carried out with conventional method, was omitted. 3) Bacterial solution of lower concentration showed higher sensitivity than that of the conventional method. Furthermore, 6 polynuclear aromatic hydrocarbons and 10 nitro compounds, some of which were found in air, were assayed in this improved method, and the results were compared to the results of the Ames test. Significantcorrelation was obtained from their results between both method.

View full abstract

In order to assess the allocation of stations, it is necessary to extract many items from different points of view and to select the items after defining the mutuality and the hierarchy among the items.
In this study, we first extracted the assessment items which were related to administration, economy and ecological effects through literature surveys and discussing with experts. Then we determined the mutuality and the hierarchy among the items by applying ISM (Interpretive Structural Modeling) method, and identified the hierarchical structure for assessing the allocation of stations.

View full abstract

Reports of air pollution effects on vegetation, which were published in Japan and foreign countries in 1981-1985, were cited (222 by Japanese language and 588 by foreign language). They include original papers, proceedings of symposium, reviews and books. They were classified and arranged with respect to the constituents of air pollution; mixed air pollutants (175), sulfur oxides (194), halogen compounds (44), photochemical oxidants (194), heavy metals (58), nitrogen oxides (35), hydrocarbons (8), aerosols (20), acid rain (65), and others (19). Numerals in parentheses are numbers of the reports cited. Contents of the reports were briefly reviewed in each constituent.

View full abstract