Analysis of exhaled VOCs from health and patients may help building association between VOCs and different diseases condition, which could offer a possibility of noninvasive monitoring of disease. VOCs were collected in 30 healthy subjects and 60 patients with upper respiratory tract infection. Analysis of 97 VOCs was
performed by gas chromatography and mass spectrometry (GC-MS). The concentration of alkanes, alkenes, halogenated hydrocarbon, oxygenated hydrocarbons and aromatic hydrocarbons in health and patients breath was analyzed. Analysis of variance (ANOVA), principal component analysis (PCA) were used to analyze the VOC differences from patients and healthy ones. The results show that the concentration of isoprene differ among patients, healthy ones and indoor air (P<0.05). Patients show higher concentration of n-pentane compared to healthy ones (P<0.05). Patients with bacterial upper respiratory tract infection show higher concentration of propanal compared to healthy ones. The results of PCA show that there were significant VOC differences between patients with upper respiratory tract infection and healthy ones (P=0.019), but no differences between bacterial and non-bacterial upper respiratory tract infection.

Indoor and outdoor fine particulate matter were sampled and analyzed in Feb.–Mar. and Nov. –Dec., 2014. The influence of ventilation condition, atmospheric pollution level, the temperature and humidity on relationship between the indoor and outdoor fine particulate matters were studied. Studies showed that ventilation and air pollution levels were two important factors affecting the indoor and outdoor relations of PM2.5, they both had effects on I/O ratio, correlation coefficient of indoor and outdoor particles as well as the contribution rate of the atmospheric PM2.5 concentrations on the indoor PM2.5 concentrations. With better ventilation condition or higher I/O ratio, indoor and outdoor correlation coefficient would be higher, as well as the outdoor contribution rate. When the atmospheric PM2.5 concentration went higher, the I/O ratio, indoor and outdoor correlation coefficient and outdoor contribution rate became higher, while the range of I/O ratio and the growth rate of outdoor contribution went less. The temperature and humidity had little effect on indoor and outdoor relations of PM2.5.

Six representative acid-base components are proposed to quantitatively characterize acid-base properties of particulate matter. Micro-titration and determination of water-soluble ion concentrations are applied to water-soluble particulate matter extract, then the acid-base balance principle and the principle of charge conservation are adopted to calculate the concentrations of representative components. Polynomial regression is conducted to analyze the relationship between the amounts of hydrogen ions neutralized by particulate matter of unit mass and the initial pH values of absorption solutions, and a series of empirical equations are obtained, which are applicable to estimate the change in pH derived by the particles absorbed by the precipitation with lower ion concentrations.

Samples for rain water were collected at four sites including Beijing city and Mazhuang Town in the north of China and Shenzhen city and Mangdang Mountain in the southeast of China. The pH values of precipitation, values of conductivity and concentrations of major water soluble ions were measured. The pH values of rainwater in Beijing City, Mazhuang Town, Shenzhen City and Mangdang Mountain were 6. 02, 5. 97, 4. 72 and 4. 81, respectively. The most abundant ions in the rainwater included SO^2-₄,NH⁺₄, Ca²⁺ and NO^-₃.SO^2-₄ was still the major acid ion in rain and NH⁺₄ was the most important neutralizing ion at these four sites. While the rainwater in the north of China was more severely polluted than that in the south, the acidity of the rain was greater in the south than that in the north. Enrichment factor was used to analyze the contribution from sea-water, soil and other sources to rainwater. Hysplit 4. 7 Model was used to indicate different chemical characters among different backward trajectories. The chemical characters of rainwater in Mazhuang Town were distinctly different among different trajectories and it was not significant among different trajectories in Shenzhen City and Mangdang Mountain.

The acute health effect due to inhalable particulate matter in the nine cities of the Pearl River Delta (PRD) was evaluated using simplified Poisson regression model. This work consulted the domestic epidemiologic studies and the meta-analysis result of exposure-response functions for health effects by the authors′team. Based on the unit economic value of each health effect endpoints, subsequent economic cost was estimated. Data citing was also more rigorous, this study mainly used results of domestic research and meta analysis results for exposure-response coefficients, in order to reflect current situation of PRD. The total economic cost caused by airborne particulate matter with aerodynamic diameters less than 10 μm ( PM₁₀ ) was estimated as approximately 0. 199 billion RMB and 0. 272 billion RMB for reference concentration of 40 μg/ m³ and 20 μg/ m³ respectively, which accounted for 0. 09‰ ( 0. 07‰-0. 11‰) and 0. 13‰ ( 0.10‰-0.15‰) gross domestic product (GDP) of PRD in 2006 respectively. Concerning acute health effect, PM_2.5 contributed over 90% among inhalable particles.

To study influences of construction fugitive in Guiyang, construction fugitive PM₁₀emission in 2002 was estimated based on an extensive survey of construction activities in Guiyang. The contribution of construction fugitive dust to ambient PM₁₀was simulated using the CALPUFF model, and the seasonal variation as well as influencing factors were addressed. The results show that fugitive PM₁₀emission from construction activities was up to 416 tons, accounting for 4% of all PM10 source emissions in the urban area of Guiyang. Construction fugitive dust showed great impact on the ambient PM₁₀level in Guiyang, and contributed 12% to the annual mean concentration of PM₁₀over the urban area. Significant seasonal variation of the contribution of construction fugitive dust was found due to the change of construction activities and meteorological conditions ( wind and precipitation).

The authors collected and analyzed three rainwater samples in Shenzhen in April and four rainwater samples in a rural area of Taian in July, 2007. The ion species in PM_2.5 and PM₁₀ concentrations were measured to get the influence of washout process of particles on ion concentrations in rainwater. Compared to that in Taian, the rainwater in Shenzhen showed higher ion concentrations and stronger acidity. The washout process made a more important contribution to ion concentrations in rainwater in Taian than in Shenzhen, because Taian had a more serious air pollution. The washout process of particles was very important. The scavenging ratios of Ca²⁺ and Mg²⁺ in PM²⁺ were high for Ca²⁺, Mg²⁺ mostly existed in coarse particles. NO^-₃, NH⁺₄, Cl^- and K⁺ mainly existed in fine particles and had smaller scavenging ratios. SO₂ and H₂SO₄ contributed a lot to the concentration of SO^2-₄ in rainwater and therefore SO^2-₄ had a high scavenging ratio.

Based on the authors investigation of the isoprene and monoterpene emissions from Hevea brasiliensis (H.B.K) Muell.-Arg in Xishuangbanna, it was found that the isoprene emission was low (emission factor varies between 0 and 1μgC·g^-1h^-1) and the monoterpene emissions were high (emission factor varies between 10 and 100μgC·g^-1h^-1). It was presumed that the scarcity of the isoprene synthase in the chloroplast of hevea brasiliensis leaves dominated the special emission character.

The experimental simulation was employed to study the atmospheric chemistry of isoprene with OH radicals in the presence of NO_x, using long-path Fourier transform infrared (LP-FTIR) method. OH radical was produced from photodissociation of CH₃ONO under irradiation of black lights. Results showed that carbonyl compounds, organic nitrates, HCOOH and CO, were formed. Methacrolein (CH₂=C(CH₃)CHO), methyl vinyl ketone (CH₃C(O)CH=CH₂) and HCHO were identified. At the temperature of 298K and the pressure of 93.3kPa, yields of methacrolein and methyl vinyl ketone were (20.8±1.5)% and (33.4±2.2)% respectively. The pressure variation did not influence their yields. Finally the reaction of isoprene with OH radical in the presence of NO_x was discussed briefly.