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Arsenic-based feed additives, such as roxarsone (ROX), are still legally and widely used in food animal production in many countries. This study was conducted to systematically characterize the content and speciation of arsenic in chicken tissues from live poultry markets and in commercial chicken feeds in Guangdong, a major poultry production and consumption province in China, and to assess the corresponding public health risk. The total arsenic contents in the commercial feeds could be modeled as a mixture of two log-normal distributions (geometric means: 0.66 and 17.5 mg/kg), and inorganic arsenic occurred at high levels (0.19-9.7 mg/kg) in those with ROX detected. In general, chicken livers had much higher contents of total arsenic compared to the muscle tissues (breast and drumstick), and chicken muscle from the urban markets contained arsenic at much higher levels than that from the rural markets. The incremental lifetime cancer risk (bladder and lung cancer) from dietary exposure to arsenic contained in chicken meat products on local markets was above the serious or priority level (10-4) for 70% and 30% of the adult populations in Guangzhou and Lianzhou, respectively. These findings indicate the significant need to phase out the use of arsenic-based feed additives in China. [ABSTRACT FROM AUTHOR]

With significant water savings and low maintenance requirements, artificial turf is increasingly promoted as a replacement for natural grass on athletic fields and lawns. However, there remains the question of whether it is an environmentally friendly alternative to natural grass. The major concerns stem from the infill material that is typically derived from scrap tires. Tire rubber crumb contains a range of organic contaminants and heavy metals that can volatilize into the air and/or leach into the percolating rainwater, thereby posing a potential risk to the environment and human health. A limited number of studies have shown that the concentrations of volatile and semivolatile organic compounds in the air above artificial turf fields were typically not higher than the local background, while the concentrations of heavy metals and organic contaminants in the field drainages were generally below the respective regulatory limits. Health risk assessment studies suggested that users of artificial turf fields, even professional athletes, were not exposed to elevated risks. Preliminary life cycle assessment suggested that the environmental impacts of artificial turf fields were lower than equivalent grass fields. Areas that need further research to better understand and mitigate the potential negative environmental impacts of artificial turf are identified. [ABSTRACT FROM AUTHOR]

As heavy metals occur naturally in soils at measurable concentrations and their natural background contents have significant spatial variations, identification and apportionment of heavy metal pollution sources across large-scale regions is a challenging task. Stochastic models, including the recently developed conditional inference tree (CIT) and the finite mixture distribution model (FMDM), were applied to identify the sources of heavy metals found in the surface soils of the Pearl River Delta, China, and to apportion the contributions from natural background and human activities. Regression trees were successfully developed for the concentrations of Cd, Cu, Zn, Pb, Cr, Ni, As, and Hg in 227 soil samples from a region of over 7.2 × 104 km2 based on seven specific predictors relevant to the source and behavior of heavy metals: land use, soil type, soil organic carbon content, population density, gross domestic product per capita, and the lengths and classes of the roads surrounding the sampling sites. The CIT and FMDM results consistently indicate that Cd, Zn, Cu, Pb, and Cr in the surface soils of the PRD were contributed largely by anthropogenic sources, whereas As, Ni, and Hg in the surface soils mostly originated from the soil parent materials. [ABSTRACT FROM AUTHOR]

This review provides an overview on the development and status of electricity generation from renewable energy sources, namely hydropower, wind power, solar power, biomass energy, and geothermal energy, and discusses the technology, policy, and finance bottlenecks limiting growth of the renewable energy industry in China. Renewable energy, dominated by hydropower, currently accounts for more than 25% of the total electricity generation capacity. China is the world's largest generator of both hydropower and wind power, and also the largest manufacturer and exporter of photovoltaic cells. Electricity production from solar and biomass energy is at the early stages of development in China, while geothermal power generation has received little attention recently. The spatial mismatch in renewable energy supply and electricity demand requires construction of long-distance transmission networks, while the intermittence of renewable energy poses significant technical problems for feeding the generated electricity into the power grid. Besides greater investment in research and technology development, effective policies and financial measures should also be developed and improved to better support the healthy and sustained growth of renewable electricity generation. Meanwhile, attention should be paid to the potential impacts on the local environment from renewable energy development, despite the wider benefits for climate change. [ABSTRACT FROM AUTHOR]

Although a potentially significant and preventable source of environmental pollution, mercury in municipal solid waste (MSW) has not received adequate attention in China. Discarded mercury-containing products, if not recycled, ultimately release mercury to air, soil, and groundwater, even after being properly collected and disposed of in MSW management facilities. This review presents an overview on mercury in MSW and describes the emissions associated with landfilling, incineration, and composting in China. Besides end-of-pipe technologies for controlling mercury emissions from MSW management, strategies for controlling mercury in MSW are also discussed, focusing on mercury source reduction and recycling. Batteries and fluorescent lamps contribute to approximately three-quarters of mercury in MSW, and are expected to remain as significant sources of mercury in the near future. Reducing or eliminating the mercury contents in household products, particularly batteries and fluorescent lamps, should be the top priority in controlling mercury in MSW, while it is also important to set mercury contents in consumer products at acceptable and achievable levels based on a life-cycle approach. Meanwhile, cost-effective recycling programs should be developed targeting products containing elemental mercury, such as medical thermometers and sphygmomanometers, and waste products with high mercury contents (e.g., button cells) as well. [ABSTRACT FROM AUTHOR]

The article examines methodologies and practices that China is employing in an attempt to curb its water shortage crisis. These challenges to water supply derive from climate and demographics and are exacerbated by pollution from waste disposal, wastewater discharge, and agricultural runoff. Water use efficiency is the most prominent method of limiting over-exploitation of water resources. Wastewater reclamation is also being applied in the country. Problems facing these efforts, including global warming and diminished water quality, are examined.

• PMF was applied for quantitative source apportionment of heavy metal(loid)s in soils • Regression and GIS-mapping were used to help interpreting the factors derived by PMF • PMF results indicate over half of Cd in the soils derived from industrial activities • Uncertainty analysis revealed large variations in the source apportionment results • Combination with other techniques can help improve the accuracy of receptor models Heavy metal(loid)s are natural constituents of the Earth's crust, and apportionment of their sources in surface soils is a challenging task. This study evaluated the application of positive matrix factorization (PMF) model, assisted with regression modeling and geospatial mapping, in the quantitative source apportionment of heavy metal(loid)s in the agricultural soils of Handan, a region covering >12,000 km2. Obvious enrichment of As, Cd, Cu, Pb, and Zn was found in the surface soils, with Cd alone accounted for 73 % of the overall potential ecological risk. PMF model revealed that Cd (56.9 %) and Pb (47.8 %) in the region's agricultural soils were predominantly contributed by industrial sources, Fe (71.8 %), Cr (60.0 %), V (52.9 %), Cu (50.7 %), Ni (42.2 %), and Mn (41.4 %) were primarily of lithogenic origin, while Co (54.1 %), As (42.9 %), and Zn (40.0 %) mainly came from the mixed sources of natural background, agricultural sources, and vehicle emissions. Uncertainty analysis showed that the contributions of pollution sources to the soil heavy metal(loid)s estimated by PMF model had considerable variations. While quantitative source apportionment of heavy metal(loid)s in soils could be achieved with PMF based on their spatial distributions, combination with emission inventory and reactive transport are probably necessary to obtain more accurate results. [ABSTRACT FROM AUTHOR]

The article reflects on the plan of China to expand its nuclear power to reduce the widespread air pollution brought by coal-fire power generation. It mentions the number of countries that have adopted the policy of nuclear power-phase out following the Fukushima nuclear accident held in March 11, 2011. It notes that the recycling of spent nuclear fuel and final disposal of high level radioactive waste is the weakest link in the nuclear power chain of China.

The article focuses on the need for research into antimicrobial resistance in factory farms in China. It states the World Health Organization and U.S. Centers for Disease Control and Prevention advocate reducing the use of microbials to prevent the emergence of resistant microbes and mentions China banned the nontherapeutic use of 150 antimicrobials in food animal production. It talks about the storage of animal wastes in lagoons and suggests veterinary medical care can safeguard animal health.

The authors discusses the significance of mercury pollution in China and the mercury level in its freshwater fishes. They are critical that despite the large contribution of China to the total mercury emission, the mercury in river fish is still below the limit in international marketing. Also mentioned are several sources of mercury emission including metal smelting, coal combustion, and artisanal gold mining.

The authors present ways to relieve water shortages in China, noting means that include transformations in economic growth, technological innovations in water conservation and treatment, and policy reforms. A mismatch in water demand and the location of water resources in China is described. China is said to be increasing its efforts to have a service-based economy, while a knowledge economy is its ultimate goal. Reduced water demands that will be realized from technological innovations in agricultural, industrial, and municipal sectors are discussed.

In this article the authors discuss China's need to control mercury (Hg) emissions as a result of the incineration of municipal solid waste (MSW). Topics include a brief overview of the environmental, health, and ecological impacts of Hg emissions, Hg emissions from MSW incineration, and various ways in which atmospheric mercury emissions from MSW incineration can be controlled, including environmental regulations.

The herbicide atrazine is a common pollutant in reservoirs and other sources of drinking water worldwide. The adsorption of atrazine from water onto zeolites CBV-720 and 4A, mesoporous silica MCM-41, quartz sand, and diatomite, and its microwave-induced degradation when sorbed on these minerals, were studied. Dealuminated HY zeolite CBV-720 exhibited the highest atrazine sorption capacity among the mineral sorbents because of its high micropore volume, suitable pore sizes, and surface hydrophobicity. Atrazine sorbed on the minerals degraded under microwave irradiation due to interfacial selective heating by the microwave, while atrazine in aqueous solution and associated with PTFE powder was not affected. Atrazine degraded rapidly in the micropores of CBV-720 under microwave irradiation and its degradation intermediates also decomposed with further irradiation, suggesting atrazine could be fully mineralized. Two new degradation intermediates of atrazine, 3,5-diamino-1,2,4-triazole and guanidine, were first identified in this study. The evolution of degradation intermediates and changes in infrared spectra of CBV-720 after microwave irradiation consistently indicate the creation of microscale hot spots in the micropores and the degradation of atrazine following a pyrolysis mechanism. These results indicate that microporous mineral sorption coupled with microwave-induced degradation could serve as an efficient treatment technology for removing atrazine from drinking water. [ABSTRACT FROM AUTHOR]