Ecological risks and potential sources of heavy metals in agricultural soils from Huanghuai Plain, China.

A total of 224 agricultural soil samples from Huanghuai Plain in China were investigated for the concentrations of seven heavy metals (As, Cd, Cr, Hg, Ni, Pb, and Zn). The mean concentrations of the metals were 12, 0.17, 79, 0.

Characterization of individual airborne particles in Taiyuan City, China.

Taiyuan, the capital of Shanxi province, China, is one of the most polluted cities in the world. To characterize the ambient particulate pollution, samples of particulates with aerodynamic diameter less than 10 microm (PM(10)) were collected during a 6-day campaign. Individual particles were analyzed by Scanning Electron Microscope with Energy-Dispersive Spectrometer (SEM-EDS) to determine their chemical composition.

Characteristics of water-soluble inorganic chemical components in size-resolved airborne particulate matters--Sheffield, UK.

To characterise the water-soluble inorganic components of PM(10) in the urban area of Sheffield, size-resolved aerosol samples were collected using an electric low pressure impactor (ELPI) during a 13-day sampling campaign in October and November 2006. Cl(-), NO(3)(-), SO(4)(2-), and NH(4)(+) were determined by ion chromatography, and Na(+), K(+), Mg(2+), and Ca(2+) by inductively coupled plasma-mass spectrometry. Back trajectories analyses revealed that the air masses could be classified into two main groups.

Soil sensitivity to acidification in Asia: status and prospects.

Exceedance of steady-state critical loads for soil acidification is consistently found in southern China and parts of SE Asia, but there is no evidence of impacts outside of China. This study describes a methodology for calculating the time to effects for soils sensitive to acidic deposition in Asia under potential future sulfur (S), nitrogen (N), and calcium (Ca) emission scenarios. The calculations are matched to data availability in Asia to produce regional-scale maps that provide estimates of the time (y) it will take for soil base saturation to reach a critical limit of 20% in response to acidic inputs.

Health benefits from reducing indoor air pollution from household solid fuel use in China--three abatement scenarios.

According to the World Health Organization (WHO), indoor air pollution (IAP) from the use of solid fuels in households in the developing world is responsible for more than 1.6 million premature deaths each year, whereof 0.42 million occur in China alone.

Urban and rural exposure to indoor air pollution from domestic biomass and coal burning across China.

Although indoor air pollution (IAP) from solid fuel use in the households of the developing countries is estimated to be one of the main health risks worldwide, there is little knowledge of the actual exposure experienced by large populations. We have developed a method to estimate exposure to PM(10) from IAP for large populations, applied to different demographic groups in China. On a national basis we find that 80%-90% of exposure in the rural population results from IAP.

Potential health benefit of reducing household solid fuel use in Shanxi province, China.

Indoor air pollution from solid fuel use has severe health effects. 60% of the Chinese population lives in rural areas, where most people rely on solid fuels for cooking and heating. We estimate exposure by combining information on the amount of time spent in different microenvironments and estimates of the particle concentrations (PM(10)) in these environments.

Heavy coal combustion as the dominant source of particulate pollution in Taiyuan, China, corroborated by high concentrations of arsenic and selenium in PM10.

Coal burning generates toxic elements, some of which are characteristic of coal combustion such as arsenic and selenium, besides conventional coal combustion products. Airborne particulate samples with aerodynamic diameter less than 10 microm (PM(10)) were collected in Taiyuan, China, and multi-element analyses were performed by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of arsenic and selenium from ambient air in Taiyuan (average 43 and 58 ng m(-3), respectively) were relatively high compared to what is reported elsewhere.

Aluminium mobilization from acidic forest soils in Leigongshan area, Southwestern China: Laboratory and field study.

Aluminium mobilization from acidic forest soils in the remote Leigongshan area in southwestern China was investigated in the field and by a laboratory batch experiment using sequential extractions with HCl solutions with pH of approximately 3.4. Experimental data showed that strongly organically bound aluminium (Alp-Alcu) decreased significantly after sequential extraction, whereas exchangeable aluminium (Alex) increased in all three horizons.

Distribution of Al-, Fe- and Mn-pools and their correlation in soils from two acid deposition small catchments in Hunan, China.

Distribution of Al-, Fe- and Mn-pools was investigated in five forest soil profiles (consisting of four horizons) in each of two Hunan catchments (BLT and LKS) where acid deposition has been considered critical. Al- and Fe-pools were higher in BLT than those in LKS, but Mn-pools much lower in BLT. Mn-pools vary from topsoils to bottom soils, but there are different trends for different Mn speciation.

Potential acidifying capacity of deposition experiences from regions with high NH4+ and dry deposition in China.

Acid rain may cause soil acidification possibly leading to indirect forest damage. Assessment of acidification potential of atmospheric deposition is problematic where dry and occult deposition is significant. Furthermore, uncertainty is enhanced where a substantial part of the potential acidity is represented by deposition of ammonium (NH(4)(+)) since the degree of assimilation and nitrification is not readily available.

Air pollution and lung cancer risks in China--a meta-analysis.

Lung cancer is a serious health problem in China, as in the rest of the world. Many studies have already proved that air pollution as well as other environmental factors can increase the risk of lung cancer. Based on epidemiological studies carried out in China, this paper proposes odds ratios (OR) to evaluate the risk of lung cancer from indoor air pollution for the Chinese population by applying the method of meta-analysis.

Chemical characterization of individual particles (PM10) from ambient air in Guiyang City, China.

PM10 samples were collected during 5 days in Guiyang, China in July 2003. A total of about 2300 particles was analyzed by an automated Scanning Electron Microscope with Energy-Dispersive Spectrometer (SEM-EDS). Hierarchical cluster analysis (HCA) was used to identify different particle types that occurred in the aerosol.

Evaluation of different approaches for modeling effects of acid rain on soils in China.

Acid deposition is an environmental problem of increasing concern in China. Acidic soils are common in the southern part of the country and soil acidification caused by acid deposition is expected to occur. Here we test and apply two different approaches for modeling effects of acid deposition and compare results with observed data from sites throughout southern China.

Effect of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate and its nonpromoting analogue 4-O-methyl-TPA on dorsal dermal melanocytes of the Syrian golden hamster (Mesocricetus auratus).

The effect of the tumor promoter TPA and its inactive structural analogue 4-O-methyl-TPA on the induction of dorsal skin melanosis in the normal Syrian golden hamster and on the promotion of melanomas in DMBA-initiated animals was investigated. Both phenomena were observed in TPA-treated hamsters but could not be detected after exposure of animals to 4-O-methyl-TPA. In contrast to results obtained with a variety of other laboratory animals, neither TPA nor 4-O-methyl-TPA were able to induce epidermal hyperplasia of hamster dorsal skin.