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Chlorinated paraffins (CPs) are hazardous to humans, and dietary intake acts as the primary pathway for human exposure to CPs. Takeout food is popular worldwide, but the presence of CPs in takeout food and its packaging is unclear. In this study, the concentrations and distributions of short- and median-chain CPs (SCCPs and MCCPs, respectively) were measured in 97 samples of four categories of takeout food and 33 samples of three types of takeout packaging. The SCCP and MCCP median concentrations for the takeout food samples were 248 and 339, 77.2 and 98.2, 118 and 258, 42.9 and 64.4 ng/g wet weight in meat, starch, half meat/half starch, and vegetables, respectively. Takeout food contained higher concentrations of SCCPs than MCCPs. The dominant SCCP and MCCP congener groups in takeout food were C 10 Cl 6–7 and C 14 Cl 7–8 , respectively. The CP concentrations in takeout food were lower than those in packaging. The SCCP and MCCP median concentrations, respectively, in packaging were 9750 and 245 ng/g in polypropylene, 2830 and 135 ng/g in paper, and 2060 and 119 ng/g in aluminum foil. The concentrations of SCCPs and MCCPs were comparable in aluminum foil, whereas the concentrations of SCCPs were higher than those of MCCPs in polypropylene and paper. Correlations between CP concentrations in the takeout food and packaging indicated that CPs in packaging were potentially an important source of CPs in the takeout food. A dietary exposure risk assessment showed the takeout food posed a low risk for human exposure to CPs; however, high-frequency consumption may pose a health risk. This study clarified the current contamination situation in takeout food in Beijing, China. The resulting data could be used to prevent human exposure to CPs through dietary intake and to facilitate the market's control over the quality of takeout food. • Chlorinated paraffin (CP) concentrations are highest in animal-origin takeout food. • CP concentrations are highest in polypropylene and lowest in aluminum foil. • Shorter carbon chain and lower chlorination CPs are dominant in food and packaging. • CPs in packaging are a potential source for CPs in takeout food. • The human exposure risk to CPs through takeout food intake is low. [ABSTRACT FROM AUTHOR]

Economic development, accompanying with environmental damage and energy depletion, becomes essential nowadays. There is a complicated and comprehensive interaction between economics, environment and energy. Understanding the operating mechanism of Energy-Environment-Economy model (3E) and its key factors is the inherent part in dealing with the issue. In this paper, we combine System Dynamics model and Geographic Information System to analyze the energy-environment-economy (3E) system both temporally and spatially, which explicitly explore the interaction of economics, energy, and environment and effects of the key influencing factors. Beijing is selected as a case study to verify our SD-GIS model. Alternative scenarios, e.g., current, technology, energy and environment scenarios are explored and compared. Simulation results shows that, current scenario is not sustainable; technology scenario is applicable to economic growth; environment scenario maintains a balanced path of development for long term stability. Policy-making insights are given based on our results and analysis. [ABSTRACT FROM AUTHOR]

One year-long criteria air pollutants data collected in Beijing were analyzed in this paper, which can support the research on formation, transport and human health effects of air pollutants. This is the first time to study the spatial and temporal variations of criteria pollutants in Beijing using hourly observational data from 12 sites between June 2014 and May 2015 released by the Ministry of Environmental Protection (MEP) of China. Beijing is facing tremendous air pollution as the daily averaged PM 2.5 (particulate matter with aerodynamic diameter less than 2.5 µm) concentrations in all sites exceeding the Chinese Ambient Air Quality Standards (CAAQS) Grade I & II standards (15 and 35 µg/m 3 ). Slightly differences in PM 2.5 and ozone (O 3 ) were observed between sites at the urban and rural areas. Pearson correlation coefficients show that most pollutants are temporally correlated in Beijing except for O 3 . The coefficients of divergence (COD) indicate that PM 2.5 is associated at most sites with only one rural site (Dingling) having observable difference and one site may be insufficient for monitoring surrounding area. The 8 h peak O 3 (O 3 -8 h) also correlates at different sites but with one urban site (Haidianquwanliu) different from others. In addition, an extreme PM 2.5 event (hourly average concentration exceeding 300 μg/m 3 for ~40 h) was examined with the consideration of meteorological conditions. Southerly wind with low speed and high relative humidity allow the accumulation of pollutants while northerly wind with high speed and low relative humidity result in good air quality. [ABSTRACT FROM AUTHOR]

The extreme high temperature weather event caused by global warming has increased the risk of urban electric power supply. Critical risk determination method is useful to the system risk prevention and adaptive strategy formulation. Based on analyzing the failure mechanism of power supply under heat wave impact, the paper put forward the method framework of energy-flow network on electric power system risk evaluation. There are three parts in the framework including energy-flow chart analysis of power supply and consumption, establishment and network analysis of Gephi visualization network, and matrix diagram evaluation of node importance. The visualized network of power system with different years and electricity input from external area were established and compared in the case study of Beijing in China. The analysis results showed that the network structure stability of the power system decreased slightly, which was due to the node energy flow becoming high imbalance such as power input from external area, local power generation and energy consumption. For risk prevention, power infrastructures should focus on the high-voltage transmission and distribution facilities and 500 kV hub substations. Meanwhile, to electric power generation and supply, natural gas supply and power supply from Inner Mongolia Autonomous Region played the key roles. And power consumption should focus on the tertiary industry and living consumption. • Energy-flow chart of power system was transformed into network by Gephi. • Node importance was evaluate by matrix diagram with node degree and edge weight. • Electric power system of Beijing was analyzed and discussed. • Energy-flow imbalance of system components reduced network system stability. [ABSTRACT FROM AUTHOR]