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Abstract: Rice plant pot experiments designed to identify benzo[a]pyrene (B[a]P) sources in plant tissues were conducted in an air-quality controlled greenhouse built to prevent contamination from B[a]P air pollution. Results from quartz sand cultures with control and 50, 100 and 500μgkg−1 of B[a]P treatments were compared with those from outdoor field experiments, in which rice plants were exposed to polluted air in the urban area of Shenyang, China. When B[a]P was strictly controlled in both air and quartz sand culture medium, the background values of B[a]P in rice plant tissues were uniformly very low. There was no significant difference of B[a]P contents of rice grain between control and treatments of B[a]P in controlled air quality trials. This indicated that the source of B[a]P in the rice grains is not from any B[a]P in the root culture media. The B[a]P content of rice grain, husk, and stem with leaf sampled from outdoor field was up to 7.33-, 9.21- and 27.10-fold higher than corresponding tissues from air-quality controlled conditions. This indicated that polluted air is the main source of B[a]P in aboveground tissues. Therefore control of B[a]P pollution in ambient air is of prime importance for improving the quality of cereal crops. [Copyright &y& Elsevier]

Abstract: The Zhangshi Irrigation Area (ZIA) in Shenyang, China has been irrigated by industrial wastewater since 1962. Since then, parts of the ZIA have been rezoned for industrial uses, but the remaining area, named Sluice Gate III (SLIII) and Lower Reaches (LR), still occupies 1825ha. Although land irrigation with industrial wastewater ceased in 1992, a study on heavy metals in soils was carried out to assess the feasibility of agricultural crop cultivation in SLIII and LR. A detailed field investigation was conducted and both total heavy metal concentrations and bioavailable fraction in soil were determined. The results have highlighted that Cd concentrations in soils still exceed the Environmental Quality Standard for Soil in China (GB15618-1995) grade C standard in SLIII region, and grade B standard in LR. In the SLIII, Zn and Pb concentrations in soil are higher than the grade A standard, although Cu is close the grade A standard. In SLIII the dominant chemical fractions were the exchangeable and carbonatic forms, which represent up to 43% and 35% of the Cd, respectively. The Cd in these two fractionations poses the highest risk for the plant absorption and accumulation. Therefore the SLIII should be abandoned for cultivated crops to prevent the Cd contamination of food chain and any associated hazards to human health. [Copyright &y& Elsevier]

• A simulation model was developed to predict performances of buildings served by DHS. • The model was evaluated using field studies conducted under cold weather conditions. • Predicted water and indoor air temperatures agree reasonably well with measurements. • Energy savings and GHG emissions were predicted for various strategies. • The model can support energy retrofit and operational strategies for buildings with DHS. District Heating Systems (DHS) have received renewed attention in relation to their environmental, economic, and health benefits. Research literature on DHS tends to focus separately, either on the thermo-hydrological modelling or building energy demand. Rarely are there combined simulation approaches that consider the interactions between the district heating system and the buildings they serve. There is a practical need for a coupled simulation model to inform operation and energy retrofit strategies, such as, building insulation, water leakage prevention, and achieving comfortable indoor air temperatures. In this study, a novel simulation model, BETHS, is developed to predict the time-varying energy performance and occupant thermal comfort of a cluster of buildings served by a DHS in the urban context. The simulation results are compared with field measurement data collected for a secondary network consisting of 12 buildings and 2788 m of pipeline network over a 10-day period, in Shenyang, Liaoning, China. Predicted water temperature and indoor air temperature showed reasonable agreements with measured data. Simulation results suggested an energy saving of 35% for improved building insulation, 32% for switching from coal to gas, 18% for reduced indoor temperature, 14% for water leakage prevention, and 67% if all are combined. The BETHS model can be a valuable extension to a building energy simulation framework, and support retrofit strategies and operational decisions for existing DHS networks. [ABSTRACT FROM AUTHOR]