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Estimation of long-term exposure to air pollution levels over a large spatial domain, such as the mainland UK, entails a challenging modelling task since exposure data are often only observed by a network of sparse monitoring sites with variable amounts of missing data. The paper develops and compares several flexible non-stationary hierarchical Bayesian models for the four most harmful air pollutants, nitrogen dioxide and ozone, and PM₁₀ and PM2.5 particulate matter, in England and Wales during the 5-year period 2007–2011. The models make use of observed data from the UK's automatic urban and rural network as well as output of an atmospheric air quality dispersion model developed recently especially for the UK. Land use information, incorporated as a predictor in the model, further enhances the accuracy of the model. Using daily data for all four pollutants over the 5-year period we obtain empirically verified maps which are the most accurate among the competition. Monte Carlo integration methods for spatial aggregation are developed and these enable us to obtain predictions, and their uncertainties, at the level of a given administrative geography. These estimates for local authority areas can readily be used for many purposes such as modelling of aggregated health outcome data and are made publicly available alongside this paper.

Industrial wastewater is the largest contributor of toxic pollutants and third-largest contributor of nutrients to bodies of water in China, and understanding the characteristics of such pollution is important for water pollution control. In this study, the industrial gray water footprint (GWF) of each industry sector in China’s 31 provinces in 2015 was calculated to identify the pollution characteristics of industrial wastewater discharge and determine how to efficiently allocate investment to pollution reduction. We show that the total industrial GWF of China was 300 billion m 3 in 2015 and that the major pollutants were petroleum pollutant (PP), ammonia nitrogen (NH 3 -N), volatile phenol (VP), and chemical oxygen demand (COD). The water pollution level (WPL) was higher than 1 in Ningxia, Shanxi, Hebei, Tianjin, Shanghai, Henan, and Shandong, indicating that industrial pollution exceeded the carrying capacity of local water bodies in these seven regions. Given equivalent total investment, a scenario that takes the total reduction of the industrial GWF weighted by the WPL in each region as the investment target can better allocate funds to control industrial wastewater pollution in regions with high WPLs relative to a scenario in which investment targets the reduction of the unweighted total industrial GWF. For further industrial GWF reduction in regions with high WPLs, it is crucial to adjust the industrial structure and to upgrade relevant technologies.

Livestock and poultry (LP) pollution affects water quality of water resources. In this study, spatio-temporal variations in amount, structure, and discharge of LP pollutant in the water source area of the Middle Route of South-to-North Water Diversion Project (MR-SNWDP) in China on the county scale were analyzed. In this regard, the gray water footprint (GWF) was employed as an indicator for quantitative evaluation of LP pollution to measure the impact of these parameters on local water resources. Based on the statistical data for the time period of 2000–2017, the results showed that the total amount of LP farming has steadily increased, except for a slight decrease in the years 2007 and 2014. Also, the counties, Dengzhou (DZ), Neixiang (NX), and Xichuan (XC), are found to be the biggest polluters. The GWF of total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) was calculated to be 12.7, 8.6, and 2.8 billion m 3 in 2017, respectively, with GWF TN  > GWF TP  > GWF COD . The pollution of TN caused by LP has a greater impact on water quality than COD and TP. In 2017, the water pollution level (WPL) of water source area is 0.28, it means LP pollution required 28% of the total local water resources to be diluted. Additionally, the WPL for DZ, NX, and XC was found to be greater than 1, and it is concluded that the water resources of these regions face an environmental threat. Based on the area scale of the water sources, policies and incidence of diseases mainly affected the changes in the number of LP farming. On the county scale, the total amount and structure of LP was affected by factors such as terrain, traffic, economic level, and breeding mode. It is recommended that different policies and disposal methods should be adopted based the LP farming conditions in different cities.

To assess the efficacy of the “Implementation Details of Air Pollution Prevention and Control Action Plan”, the chemical composition of PM 2.5 and other pollutants was determined during the winters of 2013–2014 and 2016–2017 at two urban sites in Xiangtan City, Hunan. The concentrations of PM 2.5 , SO 2 , and NO 2 decreased from 146.0 to 94.5 μg/m 3 , 75.9 to 33.5 μg/m 3 , and 80.6 to 55.8 μg/m 3 , respectively, from winter 2013–2014 to winter 2016–2017. The concentrations of almost all the major chemical components of PM 2.5 decreased as well, particularly secondary inorganic aerosols (SIAs). These results indicate that the implementation of the air quality control plan was very effective in improving air quality. Analysis of the data also suggests that SIA formation is likely responsible for high winter PM 2.5 pollution and that high relative humidity levels and low wind speed can promote the formation of SIA. A 72-h back trajectory analysis shows that both regional transport and the accumulation of local pollutants under stagnant meteorological conditions promote the occurrence of episodes of high wintertime pollution levels.

Rapid and extensive social and economic development has caused severe soil contamination by heavy metals in China. The spatial distribution, pollution levels, and health risks of metals were identified in an oasis-desert zone of northwest China. The mean concentrations of six heavy metals exceeded their corresponding background contents, and each metal concentration in farmland samples was higher than that in Gobi samples. Moreover, these heavy metals followed a similar spatial pattern and showed significant positive correlations with each other, indicating that they have the same sources. The contamination features of heavy metals and ecological risks were calculated using several quality indicators, and their health risks for population groups were quantified. The results showed that the Gobi and farmland soils were uncontaminated to moderately contaminated by heavy metals, and that farmland pollution was more serious than that of Gobi. The Gobi and farmland soils posed low ecological risks. As a whole, the non-carcinogenic risk which was caused by heavy metals was low for local residents, and the carcinogenic risk was within an acceptable level. Comparatively speaking, children were the more vulnerable population to health risks. The Zn and Cu pollution was relatively serious, and Cr and V were major contributors to health risks. Graphical abstract ᅟ

This study focused on the Chao River and Baimaguan River located upstream of the Miyun Reservoir in Miyun District (Beijing, China). Soil and sediment samples were collected from the river and drainage basin. Total nitrogen, total phosphorus, and six potentially toxic elements including cadmium, zinc, lead, chromium, arsenic, and copper, were analyzed in terms of concentration, potential ecological risk, and human health risk. The average concentrations of the six potentially toxic elements were all below the soil environmental quality standards for China. Cadmium was the most serious pollutant in both soils and sediments, at 2.58 and 3.40 times its background values. The contents of Cd and Pb were very closely related ( < 0.01) to total nitrogen concentrations in both soil and sediment samples. The potential ecological risks posed by Cd in the Chao and Baimaguan River soils were considerable and moderate, respectively. The historical iron ore mining and agricultural activity were identified as the primary sources of potentially toxic element pollution of soil and sediment in the Chao-Bai River in Miyun District. Human health risk assessment indicated that non-carcinogenic risks all fell below threshold values. The total carcinogenic risks due to Cr and As were within the acceptable range for both adults and children. This conclusion provides a scientific basis for the control of potentially toxic element pollution and environmental protection of the Miyun Reservoir in Beijing.

This paper studies the firm-level relationship among productivity, decision to export, and environmental performance. The emerging theoretical and empirical literature suggests that trade has an important role in determining firms' heterogeneity: increased openness to trade induces a real-location effect that increases within-industry efficiency, thereby linking firms' decisions to export and adopt newer (and cleaner) technology. We argue that this framework provides the following empirically-relevant predictions: there is an inverse relationship between firm productivity and pollution emissions per unit output; exporting firms have lower emissions per unit output; and larger firms have a lower emission intensity. To examine these implications empirically, we have assembled a uniquely detailed dataset of the U.S. manufacturing industry for the years 2002, 2005, and 2008 by matching facility-level air emission data from the U.S. Environmental Protection Agency with the facility's economic characteristics contained in the National Establishment Time Series database. The strategy is to first estimate a facility-level total factor productivity parameter as a plant-specific fixed effect. We then investigate how this estimated productivity parameter correlates with emission intensity on a pollutant-by-pollutant basis. Our empirical findings support the hypotheses suggested by the conceptual model. For each criteria air pollutant considered, we find a significant negative correlation between estimated facility productivity and emission intensity. Conditional on a facility's estimated productivity and other controls, exporting facilities have significantly lower emissions per value of sales than non-exporting facilities in the same industry. We also find that plant size is negatively and significantly related to emission intensity for all pollutants.

Adjusting Polish law to EU standards, many studies were started in the 1990s on the harmfulness of presumably contaminating elements (PCE) to the environment and the quality of plants intended produced for food purposes. For this reason, in 1987, a unique microplate experiment was established on natural soils artificially contaminated with copper, zinc, lead and cadmium oxides (up to the pollution level of class I, II and III). The soils were diversified in terms of pH (through liming), organic matter content (through the addition of brown coal) and the grain size composition of the humus level (Ap) (strong clay sand and light silt clay). After 14 years from the introduction of different rates of metals into the top layer (0–30 cm) of the two soils studied, relatively large movement of heavy metals in the soil profile occurred. The amount of leached metals depended mainly on the rate of a given element. The more contaminated was the soil was, the heavier the metals that leached to lower genetic levels of soil. Contaminated soils always had a higher concentration of individual metals in Et than in Bt level. The content of the tested metals in the Et layer was determined in HCl (1 mol·dm−3) and compared to the humus level. Only at the soil depth below 50 cm (Bt), the content of the studied metals’ forms was much lower than in the surface levels. The calculated mobility coefficients of the tested metals determined in 1 M HCl indicate a larger movement of the tested metals in lighter soils than in medium soils. The highest displacement coefficients were obtained for cadmium, while the lowest were for lead. An increase in mobility was obtained alongside an increase in soil contamination with the heavy metals studied. By analyzing the mobility coefficients (heavy metal increase in the Bt and Et layers), they can be ranked in the following decreasing sequence: on light soils: Cd > Cu > Zn > Pb and on medium soils: Cd > Zn > Pb > Cu.

Aviation is a basic necessity of our world, but its contribution to air pollution is considered significant. In this paper, the contribution of air traffic to air pollution levels in the area of the three larger airports of Greece is examined through the use of EDMS (Emission and Dispersion Modeling System), a regulatory model proposed by the US EPA (United States Environmental Protection Agency). To ensure a better understanding of air traffic contribution to air quality levels, the hourly aircraft movements along with the corresponding meteorological data for a whole year, 2009, were taken into account. During this year, air traffic peaked both in Greece as a total and in each of the three airports of this work. Airport emissions calculated by EDMS are found to be in good agreement with emissions monitored at Athens International Airport as well as with emission results and published data for International Zurich Airport. Concentration results have shown that PM 10 and SO 2 concentrations are well below the limit values, whereas NO 2 concentrations exceeding limit value are expected in small areas under specific circumstances, when heavy air traffic coincides with meteorological conditions favoring air pollutant accumulation. Finally, the comparison of computational results with monitoring air quality data shows a good agreement, if other sources of air pollution are excluded.

Air quality in school environments is of particular interest due to the significant amount of time children spend in these settings. Children, being a particularly sensitive demographic, are exposed to various pollutants at school or kindergarten. In this regard, our studies have focused on monitoring the concentrations of three main categories of pollutants: VOCs (volatile organic compounds), VICs and PM (particulate matter). We conducted two experimental campaigns in seven classrooms within public educational institutions. The average concentration values of TVOC (total volatile organic compounds) ranged from 554 µg/m[sup.3] to 2518 µg/m[sup.3] , of CO[sub.2] from 1055 ppm to 2050 ppm, of NH₃ (Ammonia) from 843.2 µg/m[sup.3] to 1403.4 µg/m[sup.3] , of PM2.5 from 25.1 µg/m[sup.3] to 89.9 µg/m[sup.3] , and of PM10 from 63.7 µg/m[sup.3] to 307.4 µg/m[sup.3] . In most instances, the registered values exceeded the limit values set by national or international regulations. Furthermore, this study highlights the significant impact of a heat recovery ventilation system in improving indoor air quality by substantially reducing the levels of CO[sub.2] and PM. However, it also underscores the need for further measures to more efficiently reduce TVOC concentrations. The aim of our paper was to enhance the understanding of pollution levels in school environments, increase awareness of the importance of indoor air quality, and highlight the adverse effects of polluted air on the health of occupants.