Measuring methods of personal exposures to air pollutants were reviewed. Depending upon chemical characteristics and th environmental behavior of the subjective pollutant, an appropriate sampling method should be carefully selected. Three different sampling methods, that is, a passive, an active and a real-time sampling method, were discussed using some health effect researches of air pollutants as examples.

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Combustion experiments of four types of coal-biomass briquettes in laboratory were conducted to examine sulfur-fixation ratios under simulated combustion conditions of Chinese household stoves. We evaluated the factor such as combustion temperature that affected sulfur fixation ratios. Sulfur-fixafion ratios for coal-biomass briquettes (Ca/S=2) ranged from 88% to 96% under 800°C that was assumed in previous laboratory experiments. On the contrary, those ranged from 33% to 71% under 1000°C that was observed in Chinese household stoves, which decreased from 26% to 63% for each coal-biomass briquette in comparison with those under 800°C. The decrease of sulfur-fixation ratios resulted from sulfur-emission during combustion of coal-biomass briquette char and transformation of calcium compounds in combustion ashes of coal-biomass briquettes, owing to thermal decomposition of fixed sulfur (CaSO₄) in char combustion over 850°C. Additionally, sulfur-fixation ratios under 1000°C depended on types of coals, which were different in heating value, ash contents, and metal components. The laboratory combustion results indicated the necessity and importance of selection of coal types as raw material for coal-biomass briquettes according to application in terms of reduction of sulfur-emission.

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Hourly averaged PM_2.5 and optical black carbon (OBC) were measured from 30 September to 10 October 2003 at roadside of Route 23 in Nagoya City. The average PM_2.5 concentration was 76.5 μg/m³ (n=234). The average OBC concentration was 15.5μg/m³ (n=241). OBC average contribution to PM_2.5 mass was 22.3%. There was a strong correlation between OBC and the traffic volume for heavy-duty vehicle when a roadside site was downwind of Route 23 and wind velocity was above 3m/s. EC emission factor was estimated at 368mg/km·vehicle for heavy-duty vehicle using NO_x emission facto and 261mg/km·vehicle for heavy-duty vehicle based on dispersion calculation.
Daily averaged PM_2.5 and elemental carbon (EC) were measural from January 2005 to December 2006 at an urban site in Nagoya city. The average PM_2.5 concentrations in 2005 and 2006 were 23.1μg/m³ (n= 193), and 24.6μg/m³ (n=182), respectively. The average EC concentrations in 2005 and 2006 were both 32μg/m³. Average contributions of EC to PM_2.5 in 2005 and 2006 were 15% and 14%, respectively. The average EC concentrations on weekday and on Sunday were 3.5μg/m³ and 2.0μg/m³, respectively, and EC on Sunday was 40% lower than that on weekday. The calculated concentrations of monthly average EC by ADMER (Atmospheric Dispersion Model for Exposure and Risk Assessment) at the urban site was similar to the observed concentrations.

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A new air pollution index, which is based on olfactory measurement, was proposed and it was named “Shift of Odor Index (S0I).” SOI is defined as the measurement of “the degree of interference in human odor-discrimination by environmentalair pollution” Detection of a certain kind of standard odor is measured in two cases: the odor is injected into odorless air and into the sample environmental air, respectively, and the value of SOI is calculated by the gap between two odor index values for the standaid odor. In this research, n-butanol was utilized for the standard odor gas. For the first step, triangle odor-bag method, which is Japanese standand olfactorymeasurement for the evaluation of malodor, was modified specially to enhance the detectability of the difference in the odor index values, and the calculation method for determining individual olfactory threshold was investigated. As the result, a scale to calculate thresholdvalues, dividing one step of threefold dilution series into four segments, was slightly more appropriate than the case dividing into five segments. Moreovei; SOI measurement was performed for highway peripheral atmosphere with the simultaneous observation of major air pollutants. The results showed that different characteristics are found for the air samples taken from a local main-road and for that from an expressway, about the relationship between SOI and main air pollutants. And it suggested that SOI has the possibility to become a highly unique indicator of air quality, having different features from nonmethane hydiDcalbons (NMHC). However, the detectability of SOI for acetaldehyde, which is known as the dominant odor compound in the atmospheric environment, is still considered to be lower than that of the standard measurement of odor index. Therefore, other kinds of standard odor gases must be investigated to improve the detectability of SOI.

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Changes of air quality in China were studied using the Air Pollution Index (API) data for 86 cities in the period from 2001 to 2007, which are publicized by Ministry of Environmental Protection of the People's Republic of China. In the temporal variations of API at different stations, the features showing regional scale phenomena were seen. API was generally high in winter and low in summer. Mineral dust events were seen as big spikes at more than one station at the same time. The duration of the peaks was short (1 or 2 days). As to the year-to-year variation, decrease of API was seen in several major cities such as in Beijing and Chongqing, but increase was seen in the originally clean areas such as in Haikou. The air quality in Beijing was studied using API data for 27 stations in Beijing city, 12 stations in Hebei province and for Tianjin city. The distribution and variation of API showed both regional scale and local air pollution features. The change in API of Beijing city during the traffic regulation experiment in August 2007 is also reported.

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Atmospheric measurements of PM2.5 concentration were made in summer moist condition by using β-ray absorption techniqueand FRM-LV standard method attached with PTFE/ non-woven fabric filter (TFH filters: TFH-01 and TFH-47). In the measurements of PM2.5 by using two β-ray absorption methods attached with TFH-01, we had good results for concentrations less than 50μg/m³ that a slope of linear regression (S. L) was 1.0, a correction coefficient (R) was 0.986 (n=1448), and a standard error of regression (SE) was 1.756. For parallel measurements of PM2.5 less than 50μg/ m³ concentration by FRM-LV standard method attached with TK15-G3M filter and β-ray absorption method with TFH-01, S. L and R were 1.0 and 0.992 (n=15), respectively. We thus found that TFH-01 is suitable filter evenin summer moist condition in the measurement of PM2.5 by p-my absorption technique.
Parallel measurements of atmospheric concentration of PM2.5 were made in summer moist condition by using FRM-LV standardsamplers attached with TFH-47, TK15-G3M, TX-40 and 2500QAT filters. In the concentrations less than 50μg/m³, for the measured values attached with TFH-47, SL and R of those with TK15-G3M were 1.0 and 0.996 (n=15), respectively. Whereas, S. L and R of those with TX-40 were 1.0 and 0.998 (n=15), respectively, and with 2500QAT were 1.0 and 0.989 (n=15), respectively. Therefore, TFH-47 has similar good quality with TK15-G3M, TX-40 and 2500QAT in the measurements of PM2.5 by FRM-LV standard method.
From the results, TFH are high quality filters for the measurements of PM2.5 by β-ray absorption technique and FRM-LV standard method.

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