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Heavy metal pollution is becoming a serious issue in developing countries such as China, and the public is increasingly aware of its adverse health impacts in recent years. We assessed the potential health risks in a lead-zinc mining area and attempted to identify the key exposure pathways. We evaluated the spatial distributions of personal exposure using indigenous exposure factors and field monitoring results of water, soil, food, and indoor and outdoor air samples. The risks posed by 10 metals and the contribution of inhalation, ingestion and dermal contact pathways to these risks were estimated. Human hair samples were also analyzed to indicate the exposure level in the human body. Our results show that heavy metal pollution may pose high potential health risks to local residents, especially in the village closest to the mine (V1), mainly due to Pb, Cd and Hg. Correspondingly, the residents in V1 had higher Pb (8.14 mg/kg) levels in hair than those in the other two villages. Most of the estimated risks came from soil, the intake of self-produced vegetables and indoor air inhalation. This study highlights the importance of site-specific multipathway health risk assessments in studying heavy- metal exposures in China. [ABSTRACT FROM AUTHOR]

The present study investigated contamination of polybrominated diphenyl ethers (PBDEs) in sediment and fish samples collected from rivers in Guiyu, China where electronic waste (e-waste) is recycled and disposed. PBDE congeners with mono-to hepta-brominated and deca-brominated substitutions were detected using 13C12 isotope dilution GC/MS/MS and GC/MS methods, respectively. The total PBDE concentrations ranged from 4434 to 16088 ng/g (dry weight) in Nanyang River bank sediment, from 55 to 445 ng/g in Nanyang River bottom sediment and 51.3 to 365 ng/g in Lianjiang River bottom sediment in Guiyu compared with those from 16.1 to 21.4 ng/g in wastewater discharged from a vehicle repairing workshop in Lo Uk Tsuen in Hong Kong. No PBDE congeners were detected in bottom sediment and fish from Mai Po Marshes in Hong Kong. The mean concentrations of total PBDEs in mixed muscles of tilapia (Oreochromis spp) from Lianjiang River were 115 ng/g wet weight (ww) and from wastewater in Hong Kong were 4.1 ng/g ww. Highest mean PBDE concentration was obtained in liver (2687 ng/g ww), followed by abdomen muscle (1088 ng/g ww) of bighead carp (Aristichthys nobilis) collected from Nanyang River. A significant correlation of concentration of each PBDE congener between sediment and muscle from Guiyu was observed. The present results of total PBDEs in sediment and fish were 10 and 1000 times higher than other studies. Open burning and dumping of e-waste are the major causes of PBDE contamination. [Copyright &y& Elsevier]

Abstract: South China has become the third largest region associated with acid deposition following Europe and North America, the area subject to damage by acid deposition increased from 1.75 million km² in 1985 to 2.8 million km² in 1993. Acid deposition has caused serious damage to ecosystem. Combined pollution of acid rain and SO[sub 2] showed the obvious multiple effects on crops. Vegetable was more sensitive to acid deposition than foodstuff crops. Annual economic loss of crops due to acid deposition damage in eleven provinces of south China was 4.26 billion RMB Yuan. Acid deposition caused serious damage to forest. Annual economic loss of wood volume was about 1.8 billion RMB Yuan and forest ecological benefit loss 16.2 billion in eleven provinces of south China. Acid deposition in south China was typical "sulfuric acid type". According to the thoughts of sustainable development, some strategies were brought forward as follows: (1) enhancing environmental management, specifying acid-controlling region, controlling and abating the total emission amount of SO[sub 2]; (2) selecting practical energy technologies of clean coal, for example, cleansing and selecting coal, sulfur-fixed-type industrial briqutting, abating sulfur from waste gas and so on; (3) developing other energy sources to replace coal, including water electricity, atomic energy and the new energy such as solar energy, wind energy and so on; (4) in acid deposition region of south China, selecting acid-resistant type of crop and tree to decrease agricultural losses, planting more green fertilizer crops, using organic fertilizers and liming, in order to improve buffer capacities of soil. [ABSTRACT FROM AUTHOR]

Presents information on a study which calculated the forest volume loss caused by acid deposition in seven provinces of south China. Background on the White Paper on Environment in China; Field investigations and methods; Results and discussion.

Effects of elevated 0[sub 3] on the yields of rice and winter wheat were studied by using open-top chambers(OTCs). Results showed that compared to the control treatment, 200 ppb, 100 ppb, 50 ppb treatments caused a 80.4%, 58.6% and 10.5% decrease in grain yields per winter wheat plant and a 49.1%, 26.1% and 8.2% decrease in grain yield per rice plant, respectively. According to the dose-response relation educed from OTCs experiment and the monitor data of O[sub3] concentrations in spots, it was estimated that the yield losses of rice and winter wheat resulted by O[sub3] pollution in the Yangtze River Delta region in 1999 were 0.599 million ton and 0.669 million ton, economic losses were 0.539 billion RMB Yuan and 0.936 billion RMB Yuan, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Epidemiological studies have reported that both ozone (O3) and temperature are associated with daily mortality. However, few studies have explored the interactive effect between O3 and temperature on mortality. Moreover, whether different O3 metrics influence this interaction is still unknown. This study used a Poisson generalized additive model to examine the interactive effects of daily average temperature and O3 on mortality in Suzhou between 2008 and 2009. The results showed that the O3 effects were stronger in cold season and low temperature days. On days with low temperatures (0th–25th percentile), an interquartile range increment in 1-h maximum O3 corresponded to a 15.96% (95% CI: 1.52, 32.45) increase in total mortality and an 18.77% (95% CI: 0.09, 40.95) increase in cardiovascular mortality. On days with normal temperatures (26th–75th percentile) or high temperatures (76th–100th percentile), the estimates were only 2.04% (95% CI: −5.94, 10.69) or 1.65% (95% CI: −3.21, 6.76) for total mortality, and 7.82% (95% CI: −15.21, 37.10) or 6.14% (95% CI: −17.35, 36.31) for cardiovascular mortality. Using an 8-h maximum metric yielded similar interactive effects between ozone and temperature. For total and cardiovascular mortality, evidence indicates that low temperature has a stronger modifying effect on the 1-h maximum and the maximum 8-h average O3 concentrations than the 24-h average O3 concentrations. The interaction pattern of O3 with temperature was less sensitive at different cut-offs for temperature levels and including co-pollutants in the models. Our findings provide evidence that low daily average temperature significantly modifies the acute effects of ozone on daily mortality for both the 1-h maximum metric and the maximum 8-h average metric in Suzhou, China. [Copyright &y& Elsevier]

The effects of canopy development, solar angle, and weather conditions on temporal variation in photosynthetic photon flux density(PPFD) at three heights within a tropical rain forest canopy in Xishuangbanna, China, were examined. PPFD was measured every second and stored as 10-min averages from 1 December 2002 to 30 November 2003. PPFD variability was examined at three different temporal scales. Specific days in March, September, and December with clear and overcast sky conditions were selected to separate the effects of leaf area index (LAI) and solar angle on diurnal variability. On both clear and overcast days, mean daily average PPFD was significantly different between March and September at all heights, except 10 m on clear days, suggesting that LAI directly influences PPFD. In contrast, the differences in daily average PPFD among three heights between September and December were likely due to variation in solar angle. In addition, daily average PPFD at all locations were significantly lower under overcast than clear sky conditions in March, September and December. Over the year-long study, the mean daily total PPFD at 21 m, 10 m and 4 m was 2.8, 2.7 and 0.7 mol/(m2 · d), which accounted for 9.7%, 9.4% and 2.4% of the daily PPFD above the canopy, respectively. Significant differences in mean daily total PPFD occurred at the same heights among different seasons, and diurnal, day-to-day and seasonal PPFD varied at different heights within the canopy. The possible effects of light variability on physiological and morphological responses of plants are discussed. [ABSTRACT FROM AUTHOR]

Recently, gestational diabetes mellitus (GDM) exhibits an obvious trend of increase in pregnant mothers and usually causes several abnormities or diseases for the offspring. Although several studies have been reported for potential molecular mechanisms, relevant genes or mutated sites have not been intensively investigated in China. In the present study, 218 pregnant mothers (GDM group: 103 individuals and control group: 115 individuals) in China were enrolled to conduct genome-wide association study (GWAS) and pathway analyses for the purpose of related genes associated with GDM in China. Our results identified 23 SNPs exhibiting closely association with GDM using multiple tests. Annotation of these 23 SNPs identified four genes (SYNPR, CDH18, CTIF, and PTGIS), which suggests that the four genes may associate with GDM. GO enrichment and KEGG pathway analysis showed that gene SYNPR, CDH18, and PTGIS were enriched or located into the pathways or process associated with glycometabolism (e.g. insulin resistance and glucose tolerance), which further indicates that the three genes may associate with the GDM. The identification of these potential genes associating with GDM enriched the potential molecular mechanisms of GDM in Asia and will provide abundant stocks for subsequent clinical verifications for better understanding the molecular mechanisms, diagnosis, drug development and clinical treatment of GDM. [ABSTRACT FROM AUTHOR]

The seeds of Herpetospermum pedunculosum (Ser.) C.B. Clarke, a well-known Tibetan medicine in China, are rich in kinds of bioactive lignans. In this phytochemical investigation on H. pedunculosum , sixteen undescribed lignans, named as herpedulins A - P together with 24 known ones were isolated from the ethyl acetate extract of its seeds. Their structures including the absolute configurations were determined by HR MS, 1D and 2D NMR experiments, and comparison of their experimental ECD spectra with calculated ones or literature data. High content screening experiments revealed that 9 compounds could promote the expression of farnesoid X receptor in guggulsterone-induced human normal liver cells L02 cells significantly. Further molecular docking results demonstrated that herpedulin E, J and K exhibited best docking scores (9.70, 9.28 and 10.31, respectively). Hydrogen bonding and hydrophobic interactions might contribute to the main interaction of active compounds with FXR. [Display omitted] • Sixteen undescribed compounds were isolated from Herpetospermum pedunculosum. • The absolute configurations were determined via quantum chemical calculations. • 9 compounds could promote FXR expression in guggulsterone-induced L02 cells. • Molecular interactions of compounds with FXR were analyzed by in silico methods. [ABSTRACT FROM AUTHOR]