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This study evaluated the occurrence of 36 PPCPs in urban river water samples collected from Beijing, Changzhou and Shenzhen. Twenty-eight compounds were detected. Compounds found with highest median concentrations included: sulfadimethoxine (164 ng/L), sulpiride (77.3 ng/L), atenolol (52.9 ng/L), and indomethacin (50.9 ng/L). Antibiotic was the predominant class detected and contributed about half of the overall PPCPs contamination level. Effluents from wastewater treatment plants (WWTPs) were demonstrated to be the predominant pathways through which PPCPs entering into aquatic environment in all investigated areas. The ratio of persistent PPCPs like sulpiride and carbamazepine was identified to be feasible in tracing their contamination sources in rivers. Concentrations of most detected PPCPs showed significant positive correlations with total nitrogen and total phosphorus. Two groups of representative PPCPs were selected as the chemical indicators for predicting the overall PPCPs contamination, based on the significant correlations between PPCPs. [ABSTRACT FROM AUTHOR]

Trace metals are both important micronutrients for life in the oceans, and can be tracers of various natural and anthropogenic processes. Metals including Fe, Ni, Zn, and Cu are known to be important nutrients for phytoplankton, elements including Pb are viewed primarily as anthropogenic contaminants, Cd is a biologically cycled element though it's nutritive importance is unclear, and all of these metals are impacted by overlapping natural and anthropogenic processes in different parts of the oceans. China is bordered by four marginal seas, including the Bohai, Yellow Sea (YS), East China Sea (ECS), and South China Sea. Here we present the first systematic study of trace metals in the China marginal seas from the GEOTRACES GP06CN cruise in October 2015. The metals Fe, Ni, Cu, Zn, Cd, and Pb were sampled in the Yellow Sea and East China Sea at 69 surface locations using a towfish and with 8 depth profiles, along with auxiliary parameters including salinity, phosphate, and apparent oxygen utilization. We find that Ni, Cu and Cd are most strongly impacted by a combination of biological cycling and fluvial inputs, recent atmospheric deposition dominates surface ocean Pb concentrations, and Fe and Zn are impacted by a combination of multiple processes. Comparison with historical data shows that Cu concentrations have been increasing through time, presumably due to increasing anthropogenic inputs. Ni and Cd are also delivered in high concentrations from rivers, which can reflect the impact of anthropogenic inputs, and Pb is delivered from atmospheric deposition which may include anthropogenic sources, but these metals do not show a distinct temporal trend. The six metals studied here are thus impacted by their broad-scale oceanographic distributions, local coastal processes, and anthropogenic inputs, each in different ways and to different degrees. This study represents a unique contribution to the international GEOTRACES effort, by highlighting an 'end-member' region with strong coastal and anthropogenic inputs. • Trace metal distributions in China marginal seas impacted by coastal and anthropogenic inputs. • Cu in China marginal seas has increased over the past 3 decades. • Pb concentrations on the surface are dominated by recent atmospheric input. [ABSTRACT FROM AUTHOR]

Anthropogenic activities associated with various new technologies are increasingly disrupting the geochemical cycles of rare earth elements (REEs). For example, samarium (Sm) and gadolinium (Gd) have emerged as microcontaminants in the natural waters of developed areas. Surface water samples of 13 urban lakes were collected in Wuhan, the largest city in central China, with a population of over 11 million. The aim of this study was to examine to what extent REE anomalies occur and the relationship between the concentration of anthropogenic REEs in lakes and the surrounding environment. In this study, based on land-use type and point of interest (POIs) data, buffer extraction, density estimation and Spearman correlation analysis were first proposed to identify different sources of anthropogenic REEs, which mainly included hospitals, factories, population, urban land and cropland. The PAAS-normalized REE patterns indicate that all lake samples display pronounced positive Sm and Gd anomalies, ranging from 5.92 to 19.88 and 1.73 to 14.97, respectively. Spearman correlation analysis showed that hospital density was positively correlated with anthropogenic Gd concentration, and a positive relationship between proportion of cropland and the concentration of anthropogenic Sm. By utilizing Gd anth , Sm anth , and the conventional ion ratio (NO 3 −/Cl−), a three-dimensional tracer system was established, and the system accurately obtained a characterization of the impact of WWTPs, hospitals, factories and agriculture on the lakes. Moreover, the results from this hydrochemical method were consistent with the analysis of geographic information systems, which indicated that this anthropogenic contaminant as a tracer was reliable for analysing the source of urban water pollution. [Display omitted] • REEs were studied in urban lakes of the largest city in central China. • Agriculture, hospitals and WWTP greatly affected the patterns of REEs in urban water environment. • The highest anomaly Gd value was found in the central region, decreasing with distance from urban core. • First reported that anthropogenic Sm concentration linearly correlates to the proportion of cropland around the lakes. • Combination of anthropogenic REEs and traditional ions could provide promising insights into tracing human activities. [ABSTRACT FROM AUTHOR]

Abstract: In order to investigate the source of Pb within the Yangtze River intertidal zone, studying Pb isotope ratios is a likely approach because the ratios of these Pb isotopes can be used to identify the natural or anthropogenic origin of Pb. In this study, a total of 59 surface sediment samples (<5 cm) were collected during 2004 and 2005 from 26 sites in the Yangtze River intertidal zone. We measured the total Pb concentrations and Pb isotopes (204Pb, 206Pb, 207Pb and 208Pb) and found that the total Pb concentrations varied from 18.3 to 44.1 mg kg−1 with an average concentration of 27.3 mg kg−1. The observed Pb isotope ratios, excluding one station near Shanghai Pudong Airport which is significantly influenced by anthropogenic sources, varied from 18.459 to 18.750 for 206Pb/204Pb, 15.628 to 15.728 for 207Pb/204Pb, and 38.715 to 39.213 for 208Pb/204Pb. This study shows that Pb found within the Yangtze River intertidal zone sediments was mainly from the catchment in the Yangtze River watershed. Significant Pb pollution was not discerned in the Yangtze River intertidal zone. However, Pb contamination in some localized areas was suggested by Pb enrichment factor (EF). [Copyright &y& Elsevier]

The impacts of biomass burning have not been adequately studied in China. In this work, chemical compositions of volatile organic compounds and particulate organic matters were measured in August 2005 in Beijing and in October 2004 in Guangzhou city. The performance of several possible tracers for biomass burning is compared by using acetonitrile as a reference compound. The correlations between the possible tracers and acetonitrile show that the use of K+ as a tracer could result in bias because of the existence of other K+ sources in urban areas, while chloromethane is not reliable due to its wide use as industrial chemical. The impact of biomass burning on air quality is estimated using acetonitrile and levoglucosan as tracers. The results show that the impact of biomass burning is ubiquitous in both suburban and urban Guangzhou, and the frequencies of air pollution episodes significantly influenced by biomass burning were 100% for Xinken and 58% for downtown Guangzhou city. Fortunately, the air quality in only 2 out of 22 days was partly impacted by biomass burning in August in Beijing, the month that 2008 Olympic games will take place. The quantitative contribution of biomass burning to ambient PM2.5 concentrations in Guangzhou city was also estimated by the ratio of levoglocusan to PM2.5 in both the ambient air and biomass burning plumes. The results show that biomass burning contributes 3.0–16.8% and 4.0–19.0% of PM2.5 concentrations in Xinken and Guangzhou downtown, respectively. [Copyright &y& Elsevier]

The article presents abstracts of several studies on environmental geochemistry. Some of the abstracts presented include "Biogeochemical Cycling of Nutrients in Karstic Catchments, Southwestern China: Linkages to Changes of Eco-Environments," by Congqiang Liu and "Emerging Organic Contamination in China," by Guibin Jiang and colleagues.

Abstract: Beijing is a rapidly developing city with severe and unique air pollution problems. Organic matter is the most abundant fraction in fine particles in Beijing, occupying 30–50% of the total mass, indicating its key role in air pollution control. However, detailed chemical characterization of particulate organic matter in Beijing has never been reported. In this study, fine particles in the urban atmosphere in Beijing were investigated for its organic components by GC/MS technique. Over 100 individual organic compounds were identified and quantified in 25 PM2.5 samples from the summer, autumn and winter of 2002–2003. Alkanes, fatty acids, dicarboxylic acids, polycyclic aromatic hydrocarbons and some important tracer compounds (hopanes, levoglucosan and steroids) were the major constituents with the sum of their concentrations of 502, 1471 and 1403 ng m−3 in summer, autumn and winter, respectively. Different organic compounds presented apparently different seasonal characteristics, reflecting their different dominant emission sources, such as coal combustion, biomass burning and cooking emission. The abundance and origin of these organic compounds are discussed to reveal seasonal air pollution characteristics of Beijing. [Copyright &y& Elsevier]

Significant dust storm impacts have seldom been recorded and reported in Hong Kong. Herein, four cases which occurred in Hong Kong during the spring times of recent years are examined using back-trajectory computation and chemical analysis of air-borne samples. All of the cases show that the dust was transported from the source to Hong Kong in 2–5 days and that PM10 concentrations approached or exceeded the European Union air quality criteria and the USA National Ambient Air Quality Standard. The chemical characteristics of the samples taken in these events agreed both with those from the source regions and with those archived from selected Hong Kong datasets. The concentrations of the crustal constituents (Al, Fe, Mn, Ca) of the Hong Kong samples on the episode days were at least three times higher than the concentrations measured on non-episode days. The mass ratios of Fe/Al and Mn/Al (but not Ca/Al) can act as good tracers of Asian dust storms to this coastal site where sea-salt and other anthropogenic species are normally dominant. Furthermore, unusually high Mg levels indicated a mainly crustal origin for this element, rather than the marine origin normally found at this coastal location. Particulate nitrate exhibited more elevated concentrations in all of the dust storm samples than in non-dust-storm and local samples. [ABSTRACT FROM AUTHOR]

Recently, emerging pollutants, such as anthelmintics have attracted an increasing attention worldwide due to their extensive use and notable stability. However, the information on anthelmintics in the environment of southwest China is scarce. Thus, the occurrence, ecological risk and exposure evaluation of nineteen anthelmintics in Tuojiang River, which is one of the largest tributaries of Yangtze River, and drinking water source of Sichuan, southwest China, were investigated. The result showed that the detection frequency of anthelmintics was relatively high in Tuojiang River, ranging from 65% to 100% in river water. Among the seven kinds of anthelmintics, benzimidazoles are the primary anthelmintics, with concentrations up to 61.12 ng/L and 596.06 ng/g in water and sediment of the Tuojiang river, respectively. The total concentration of 19 anthelmintics in sediment samples from non-agricultural area was higher than that in agricultural area(p = 0.000 < 0.05). This could be attributed to anthropogenic activities, which lead to greater discharge and accumulation of anthelmintics in residential area along the river. It's worth to mention that the highest total concentrations of anthelmintics (109.28 ng/L) was found at the junction of rivers in R31 site. The results could be ascribed to the complexity of junction of Tuojiang River and Yangtze River, which could influence the distribution of pollutant. Besides, the ecological risk assessment showed that the macrocyclic lactones rather than benzimidazoles had relatively high toxicity to non-target organisms in aquatic environment (p = 0.000 < 0.05), with the highest RQ Ecotox value of 101 for Daphnia magna , while benzimidazoles had relatively high concentrations. The exposure risk could be ignored for both children and adults because the daily intake of anthelmintics via water ingestion were below 10 ng/kg/d. In addition, strong correlations were found between sucralose and most of the selected anthelmintics in Tuojiang River, indicating that sucralose might be a good tracer to evaluated the source of anthelmintics in surface water. This study provides the levels, risks and even some tracer information of pollutants for better understanding of anthelmintics in southwest China. • Benzimidazoles were the primary pollutant for anthelmintics in water and sediments from Tuojiang River. • Macrocyclic lactones posed the mainly ecological risk with the highest RQ Ecotox value for Daphnia magna. • There was no obvious exposure risk for both children and adults via water ingestion. • Sucralose could be a suitable tracer for anthelmintics in surface water. [ABSTRACT FROM AUTHOR]

• The Zn content and δ66Zn (−0.11‰~0.41‰) of SPM in Zhujiang River varied distinctly. • Up to 83% fluvial Zn was transported in suspended loads in the Zhujiang River. • Zn isotope and enrichment factor can effectively trace the Zn sources in river SPM. • Anthropogenic and natural inputs contributed 30.2% and 69.8% to Zn in SPM. The distinct isotopic composition of metallic elements observed in different sources and reservoirs provides an important perspective on tracing the source, transportation, and circulation of metal pollutants. As an essential trace element for life, Zinc (Zn) will show strong toxicity when its concentration reaches a certain limit. The riverine suspended particulate matter (SPM) is the common occurrence state of Zn. However, few studies have examined the sources and isotope of Zn in SPM. To examine the origins of Zn in SPM, the Zn isotope (δ66Zn) and Zn contents of SPM from 22 sites in the Zhujiang River were investigated and the relative contributions of potential sources to particulate Zn were also calculated. The results indicate that the Zn concentrations have a large variation from 49 to 733 mg kg−1 and a relatively higher enrichment level (EF Zn , up to 20.8). The percentage of Zn transportation in the form of SPM ranges between 9% and 97% (average 83%) in the Zhujiang River. The roughly negative correlation is reflected between EF Zn and δ66Zn (−0.11‰ to 0.41‰). Based on isotopic mass balance, the contribution of the natural and anthropogenic sources was calculated. The relative proportion of particulate Zn derived from anthropogenic inputs is 30.2%, while the natural source contributes 69.8% Zn to the fluvial SPM. These results further indicate that Zn is controlled by both the natural and anthropogenic inputs. Moreover, the preliminary application of Zn isotope shown in this study highlights the metallic isotope can be an effective indicator of the riverine eco-environmental pollution. [ABSTRACT FROM AUTHOR]

Focuses on a study of an oxygen isotope as a tracer of rare earth element fractionation in water-rock interaction in the Lemachang independent silver deposit in Yunnan, China. Geology of the Lemachang deposit; Samples and analysis; Discussion and conclusions.

The Bohai Sea is a semi-enclosed shallow sea in China, where the tides and wind are the dominant factors contributing to the water exchange with the Yellow Sea. However, existing studies on this water exchange primarily consider only the effect of tidal action, neglecting the contribution of wind. In this study, numerical models were used to simulate the hydrodynamic processes and tracer transport, with the consideration of both tides and wind. Based on the models, the two time scales, age and half-life, are applied to study the water exchange in the Bohai Sea quantitatively. The results show that the age and half-life decrease significantly when wind is included in the simulation, revealing that wind is an important contributor to the water exchange in such a semi-enclosed shallow sea. Under the combined forcing of tides and wind, the water transport in the Bohai Sea becomes clockwise, in contrast with the counterclockwise transport driven by the tides only. The seasonal-varying wind leads to a fluctuation of water exchange in an annual cycle, with the stronger water exchange in the northern (Liaodong Bay) and the western (Bohai Bay) regions of the Bohai Sea in winter and in the southern part (Laizhou Bay) in summer. [ABSTRACT FROM AUTHOR]

Many factors influence the evaluation process of thief zones. The evaluation index contains very complex information. How to quickly obtain effective information is the key to improve the evaluation quality for thief zones. Considering that the correlation and information redundancy among the evaluation indexes will seriously affect the evaluation results for the thief zone, based on the principal component analysis (PCA) method, this paper proposes a multi-layer weighted principal component analysis method (MLWPCA). Firstly, factor analysis is performed on the original data to obtain the plurality subsystems of the evaluation index. Then, a principal component is analyzed through the subsystems of the evaluation index PCA to obtain the principal component score. Finally, the subsystem is weighted by the factor score and the comprehensive thief zone score is obtained by combining the subsystem weight and the subsystem score. A case study on the Daqing oilfield shows the effectiveness of the method, verified by tracer tests when applying the MLWPCA method to evaluate the thief zone. The thief zone of the Daqing oilfield is obviously affected by effective thickness, coefficient of permeability variation and interwell connectivity. At present, there are 10 well developed thief zones and eight medium developed thief zones in Daqing oilfield. The accuracy of this method is 94.44%. Compared with PCA, this method has better pertinence in evaluating thief zones, and is more effective in determining the principle influencing factors. [ABSTRACT FROM AUTHOR]