The impact of surface ozone pollution on winter wheat yield is empirically estimated by considering socio-economic and weather determinants. This research is the first to use an economic framework to estimate the ozone impact, and a unique county-level panel is employed to examine the impact of the increasing surface ozone concentration on the productivity of winter wheat in China. In general, the increment of surface ozone concentration during the ozone-sensitive period of winter wheat is determined to be harmful to its yield, and a conservative reduction of ozone pollution could significantly increase China's wheat supply.

Spatial-temporal distributions, sources identification and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in overlying water and surface sediments in urban river networks of Shanghai were studied. Analytical results showed that there was a significant seasonal variation in concentrations of ∑16PAHs in water, suspended particulate matter (SPM) and sediment phases in this study area. The PAHs pollution in these multi-phases were in the medium level compared with other areas around the world, and the levels of PAHs contamination in SPM and sediment phases in hierarchical rivers showed TS (the third-order stream) > FS (the first-order stream) > SS (the second-order stream). Two manners of isomer ratios and principal component analysis (PCA) were used to identify PAHs origins, and suggested that combustion processes are dominant for PAHs sources. The ratios of PAHs origins by fossil fuels combustion, coke burning and crude oil in hierarchical rivers were determined with FS > SS > TS in SPM and sediment phases, and the ratio of PAHs origins by traffic emissions was analyzed with TS > SS > FS. PAHs in water samples have a certain impact on aqueous ecological system especially due to the fact that the ∑ceq values of nine PAHs were calculated from 0.715 to 15.831 μg/L in winter, which inferred serious ecological risk to some special aquatic organisms. The calculations of MERMQ in sediment samples showed that the MERMQ values ranged from 0.021 to 1.209 in winter and 0.019 to 0.643 in summer, which suggested high toxicity at six sampling sites in winter and only one location in summer due to high levels of PAHs. Furthermore, the toxicity degree of sediments were demonstrated with TS > FS > SS.

Trees remove air pollutants through dry deposition processes depending upon forest structure, meteorology, and air quality that vary across space and time. Employing nationally available forest, weather, air pollution and human population data for 2010, computer simulations were performed for deciduous and evergreen trees with varying leaf area index for rural and urban areas in every county in the conterminous United States. The results populated a national database of annual air pollutant removal, concentration changes, and reductions in adverse health incidences and costs for NO2, O3, PM2.5 and SO2. The developed database enabled a first order approximation of air quality and associated human health benefits provided by trees with any forest configurations anywhere in the conterminous United States over time.Comprehensive national database of tree effects on air quality and human health in the United States was developed.

This research investigated the use of two relatively cost-effective devices for determining NH3 concentrations in naturally ventilated (NV) dairy barns including an Ogawa passive sampler (Ogawa) and a passive flux sampler (PFS). These samplers were deployed adjacent to sampling ports of a photoacoustic infrared multigas spectroscope (INNOVA), in a NV dairy barn. A 3-day deployment period was deemed suitable for both passive samplers. The correlations between concentrations determined with the passive samplers and the INNOVA were statistically significant (r = 0.93 for Ogawa and 0.88 for PFS). Compared with reference measurements, Ogawa overestimated NH3 concentrations in the barn by ∼14%, while PFS underestimated NH3 concentrations by ∼41%. Barn NH3 emission factors per animal unit (20.6–21.2 g d⁻¹ AU⁻¹) based on the two passive samplers, after calibration, were similar to those obtained with the reference method and were within the range of values reported in literature.

The aim of this study was to identify how hydrologic factors (e.g., rainfall, maximum depth, reservoir and catchment area, and water residence time) and water chemistry factors (e.g., conductivity, pH, suspended particulate matter, chlorophyll-a, dissolved organic carbon, and sulfate) interact to affect the spatial variance in monomethylmercury (MMHg) concentration in nine artificial reservoirs. We hypothesized that the MMHg concentration of reservoir water would be higher in eutrophic than in oligotrophic reservoirs because increased dissolved organic matter and sulfate in eutrophic reservoirs can promote in situ production of MMHg. Multiple tools, including Pearson correlation, a self-organizing map, and principal component analysis, were applied in the statistical modeling of Hg species. The results showed that rainfall amount and hydraulic residence time best explained the variance of dissolved Hg and dissolved MMHg in reservoir water. High precipitation events and residence time may mobilize Hg and MMHg in the catchment and reservoir sediment, respectively. On the contrary, algal biomass was a key predictor of the variance of the percentage fraction of unfiltered MMHg over unfiltered Hg (%MMHg). The creation of suboxic conditions and the supply of sulfate subsequent to the algal decomposition seemed to support enhanced %MMHg in the bloom reservoirs. Thus, the nutrient supply should be carefully managed to limit increases in the %MMHg/Hg of temperate reservoirs.

We estimated net annual temperature-related mortality in Brisbane, Sydney and Melbourne in Australia using 62 global climate model projections under three IPPC SRES CO2 emission scenarios (A2, A1B and B1). In all cities, all scenarios resulted in increases in summer temperature-related deaths for future decades, and decreases in winter temperature-related deaths. However, Brisbane and Sydney will increase the net annual temperature-related deaths in the future, while a slight decrease will happen in Melbourne. Additionally, temperature-related mortality will largely increase beyond the summer (including January, February, March, November and December) in Brisbane and Sydney, while temperature-related mortality will largely decrease beyond the winter in Melbourne. In conclusion, temperature increases for Australia are expected to result in a decreased burden of cold-related mortality and an increased burden of heat-related mortality, but the balance of these differences varied by city. In particular, the seasonal patterns in temperature-related deaths will be shifted.

Polycyclic aromatic hydrocarbons (PAHs), nicotine, cotinine, and metals in human hair have been used as important environmental exposure markers. We aimed to develop a simple method to simultaneously analyze these pollutants using a small quantity of hair. The digestion performances of tetramethylammonium hydroxide (TMAH) and sodium hydroxide (NaOH) for human hair were compared. Various solvents or their mixtures including n-hexane (HEX), dichloromethane (DCM) and trichloromethane (TCM), HEX:DCM32 (3/2) and HEX:TCM73 (7/3) were adopted to extract organics. The recoveries of metals were determined under an optimal operation of digestion and extraction. Our results showed that TMAH performed well in dissolving human hair and even better than NaOH. Overall, the recoveries for five solutions were acceptable for PAHs, nicotine in the range of 80%–110%. Except for HEX, other four extraction solutions had acceptable extraction efficiency for cotinine from HEX:TCM73 (88 ± 4.1%) to HEX:DCM32 (100 ± 2.8%). HEX:DCM32 was chosen as the optimal solvent in consideration of its extraction efficiency and lower density than water. The recoveries of 12 typical major or trace metals were mainly in the range of 90%–110% and some of them were close to 100%. In conclusion, the simultaneous analysis of PAHs, nicotine, cotinine, and metals was feasible. Our study provided a simple and low-cost technique for environmental epidemiological studies.

Studies focused on pollutants deposition on vegetation surfaces or aerodynamics of vegetation space conflict in whether vegetation planting can effectively reduce airborne particulate matter (PM) pollution. To achieve a more comprehensive understanding of the conflict, we conducted experiments during 2013 and 2014 in Beijing, China to evaluate the importance of vegetation species, planting configurations and wind in influencing PM concentration at urban and street scales. Results showed that wind field prevailed over the purification function by vegetation at urban scale. All six examined planting configurations reduced total suspended particle along horizontal but not vertical direction. Shrubs and trees–grass configurations performed most effectively for horizontal PM2.5 reduction, but adversely for vertical attenuation. Trapping capacity of PMs was species-specific, but species selection criteria could hardly be generalized for practical use. Therefore, design of planting configuration is practically more effective than tree species selection in attenuating the ambient PM concentrations in urban settings.

We analyzed concentrations, distribution characteristics, and health risks of endosulfan (α and β isomers, and endosulfan sulfate) in soils (top soils and soil profiles) and air, at and around a typical endosulfan production site in Jiangsu, China. The air–soil surface exchange flux is calculated to investigate transport dynamics of endosulfan. Concentrations at the production site ranged from 0.01 to 114 mg/kg d.w. in soil and 4.81–289 ng/m3 in air, with very high concentrations occurring at the location of endosulfan emulsion workshop. In the surrounding area, endosulfan was detected in all samples, with concentrations ranging from 1.37–415 ng/g d.w. in soil and 0.89–10.4 ng/m3 in air. In the contaminated site, endosulfan concentrations fluctuated with depth in the upper soil layers, then decreased below 120 cm. Soil and air within a distance of 2.0 km appear to be affected by endosulfan originating from the site. Even the health risk at the location of the endosulfan emulsifiable solution workshop was over seven times the acceptable value, the risk to nearby adults and children was low.

The effect of elevation and rooftop configuration on local air quality was investigated at the Brooklyn Grange rooftop farm during a short-term observational campaign. Using multiple particle counters and sonic anemometers deployed along vertical gradients, we found that PM2.5 concentration decayed with height above the street. Samples adjacent to the street had the highest average PM2.5 concentration and frequent stochastic spikes above background. Rooftop observations 26 m above ground showed 7–33% reductions in average PM2.5 concentration compared with the curbside and had far fewer spikes. A relationship between the vertical extinction rate of PM2.5 and atmospheric stability was found whereby less unstable atmosphere and greater wind shear led to greater PM2.5 extinction due to damped vertical motion of air.