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Divergent responses of methanogenic archaeal communities in two rice cultivars to elevated ground-level O3 Full text
2016
Zhang, Jianwei | Tang, Haoye | Zhu, Jianguo | Lin, Xiangui | Feng, Youzhi
Inhibitive effect of elevated ground-level ozone (O3) on paddy methane (CH4) emission varies with rice cultivars. However, little information is available on its microbial mechanism. For this purpose, the responses of methane-metabolizing microorganisms, methanogenic archaea and methanotrophic bacteria to O3 pollution were investigated in the O3-tolerant (YD6) and the O3-sensitive (IIY084) cultivars at two rice growth stages in Free Air Concentration Elevation of O3 (O3-FACE) system of China. It was found that O3 pollution didn't change the abundances of Type I and Type II methanotrophic bacteria at two rice stages. For methanogenic archaea, their abundances in both cultivars were decreased by O3 pollution at the tillering stage. Furthermore, a greater negative influence on methanogenic archaeal community was observed on IIY084 than on YD6: at tillering stage, the alpha diversity indices of methanogenic archaeal community in IIY084 was decreased to a greater extent than in YD6; IIY084 shifted methanogenic archaeal community composition and decreased the abundances and the diversities of Methanosarcinaceae and Methanosaetaceae as well as the abundance of Methanomicrobiales, while the diversity of Methanocellaceae were increased in YD6. These findings indicate that the variations in the responses of paddy CH4 emission to O3 pollution between cultivars could result from the divergent responses of their methanogenic archaea.
Show more [+] Less [-]Contaminants of emerging concern in a large temperate estuary Full text
2016
Meador, James P. | Yeh, Andrew | Young, Graham | Gallagher, Evan P.
This study was designed to assess the occurrence and concentrations of a broad range of contaminants of emerging concern (CECs) from three local estuaries within a large estuarine ecosystem. In addition to effluent from two wastewater treatment plants (WWTP), we sampled water and whole-body juvenile Chinook salmon (Oncorhynchus tshawytscha) and Pacific staghorn sculpin (Leptocottus armatus) in estuaries receiving effluent. We analyzed these matrices for 150 compounds, which included pharmaceuticals, personal care products (PPCPs), and several industrial compounds. Collectively, we detected 81 analytes in effluent, 25 analytes in estuary water, and 42 analytes in fish tissue. A number of compounds, including sertraline, triclosan, estrone, fluoxetine, metformin, and nonylphenol were detected in water and tissue at concentrations that may cause adverse effects in fish. Interestingly, 29 CEC analytes were detected in effluent and fish tissue, but not in estuarine waters, indicating a high potential for bioaccumulation for these compounds. Although concentrations of most detected analytes were present at relatively low concentrations, our analysis revealed that overall CEC inputs to each estuary amount to several kilograms of these compounds per day. This study is unique because we report on CEC concentrations in estuarine waters and whole-body fish, which are both uncommon in the literature. A noteworthy finding was the preferential bioaccumulation of CECs in free-ranging juvenile Chinook salmon relative to staghorn sculpin, a benthic species with relatively high site fidelity.
Show more [+] Less [-]Cadmium-induced immune abnormality is a key pathogenic event in human and rat models of preeclampsia Full text
2016
Zhang, Qiong | Huang, Yinping | Zhang, Keke | Huang, Yanjun | Yan, Yan | Wang, Fan | Wu, Jie | Wang, Xiao | Xu, Zhangye | Chen, Yongtao | Cheng, Xue | Li, Yong | Jiao, Jinyu | Ye, Duyun
With increased industrial development, cadmium is an increasingly important environmental pollutant. Studies have identified various adverse effects of cadmium on human beings. However, the relationships between cadmium pollution and the pathogenesis of preeclampsia remain elusive. The objective of this study is to explore the effects of cadmium on immune system among preeclamptic patients and rats. The results showed that the cadmium levels in the peripheral blood of preeclamptic patients were significantly higher than those observed in normal pregnancy. Based on it, a novel rat model of preeclampsia was established by the intraperitoneal administration of cadmium chloride (CdCl2) (0.125 mg of Cd/kg body weight) on gestational days 9–14. Key features of preeclampsia, including hypertension, proteinuria, placental abnormalities and small foetal size, appeared in pregnant rats after the administration of low-dose of CdCl2. Cadmium increased immunoglobulin production, mainly angiotensin II type 1-receptor-agonistic autoantibodies (AT1-AA), by increasing the expression of activation-induced cytosine deaminase (AID) in B cells. AID is critical for the maturation of antibody and autoantibody responses. In addition, angiotensin II type 1-receptor-agonistic autoantibody, which emerged recently as a potential pathogenic contributor to PE, was responsible for the deposition of complement component 5 (C5) in kidneys of pregnant rats via angiotensin II type 1 receptor (AT1R) activation. C5a is a fragment of C5 that is released during C5 activation. Selectively interfering with C5a signalling by a complement C5a receptor-specific antagonist significantly attenuated hypertension and proteinuria in Cd-injected pregnant rats. Our results suggest that cadmium induces immune abnormalities that may be a key pathogenic contributor to preeclampsia and provide new insights into treatment strategies of preeclampsia.
Show more [+] Less [-]Dandelion Taraxacum linearisquameum does not reflect soil metal content in urban localities Full text
2016
Kováčik, Jozef | Dudáš, Matej | Hedbavny, Josef | Mártonfi, Pavol
Accumulation of selected heavy metals (Cd, Pb, Ni, Cr, Fe, and Zn) and phenolic metabolites (total soluble phenols, cichoric and caftaric acid) in dandelion organs (leaves, roots, inflorescences/anthodia) collected from six localities within the industrial town Košice (eastern Slovakia) were studied. Localities from the vicinity of a steel factory (Cd, Fe) and heavy traffic (Pb, Ni, Cr, Zn) contained the highest amount of individual metals in the soil but a significant correlation between soil and organ metal content was found only for Cr in the leaves (r2 = 0.7679). The amount of Cd and partially Pb differed among localities in all organs and especially in the leaves and anthodia, indicating probably the impact of atmospheric pollution. The bioaccumulation factor was <1 for almost all metals, suggesting that given dandelion species is not metal accumulator. Translocation factor did not reach values close to or over 1 only for Cd, indicating a root-to-shoot movement of Pb, Ni and Zn though the impact of air pollution on leaves cannot be excluded. A strong correlation between leaf Cd and leaf total phenols, cichoric and caftaric acids was observed (r2 = 0.7926, 0.8682 and 0.8830, respectively), indicating that phenolic metabolites act in the protection of dandelion against Cd excess. Overall, our data indicate low pollution of urban soil by Cd (5.53–113.8 ng g−1) and partially by Cr and the suitability of above-ground organs of dandelion species for the monitoring of air pollution mainly by Cd.
Show more [+] Less [-]Is standard deviation of daily PM2.5 concentration associated with respiratory mortality? Full text
2016
Lin, Hualiang | Ma, Wenjun | Qiu, Hong | Vaughn, Michael G. | Nelson, Erik J. | Qian, Zhengmin | Tian, Linwei
Studies on health effects of air pollution often use daily mean concentration to estimate exposure while ignoring daily variations. This study examined the health effects of daily variation of PM2.5. We calculated daily mean and standard deviations of PM2.5 in Hong Kong between 1998 and 2011. We used a generalized additive model to estimate the association between respiratory mortality and daily mean and variation of PM2.5, as well as their interaction. We controlled for potential confounders, including temporal trends, day of the week, meteorological factors, and gaseous air pollutants. Both daily mean and standard deviation of PM2.5 were significantly associated with mortalities from overall respiratory diseases and pneumonia. Each 10 μg/m3 increment in daily mean concentration at lag 2 day was associated with a 0.61% (95% CI: 0.19%, 1.03%) increase in overall respiratory mortality and a 0.67% (95% CI: 0.14%, 1.21%) increase in pneumonia mortality. And a 10 μg/m3 increase in standard deviation at lag 1 day corresponded to a 1.40% (95% CI: 0.35%, 2.46%) increase in overall respiratory mortality, and a 1.80% (95% CI: 0.46%, 3.16%) increase in pneumonia mortality. We also observed a positive but non-significant synergistic interaction between daily mean and variation on respiratory mortality and pneumonia mortality. However, we did not find any significant association with mortality from chronic obstructive pulmonary diseases. Our study suggests that, besides mean concentration, the standard deviation of PM2.5 might be one potential predictor of respiratory mortality in Hong Kong, and should be considered when assessing the respiratory effects of PM2.5.
Show more [+] Less [-]Cross-sectional association between exposure to particulate matter and inflammatory markers in the Japanese general population: NIPPON DATA2010 Full text
2016
Michikawa, Takehiro | Okamura, Tomonori | Nitta, Hiroshi | Nishiwaki, Yuji | Takebayashi, Toru | Ueda, Kayo | Kadota, Aya | Fujiyoshi, Akira | Ohkubo, Takayoshi | Ueshima, Hirotsugu | Okayama, Akira | Miura, Katsuyuki
A suggestive mechanism behind the association between particulate matter and cardiovascular disease is inflammatory response. Earlier population-based studies investigating the association between particulate matter and inflammatory biological markers, in particular C-reactive protein (CRP), showed inconsistent results. In addition, evidence from the Asian population, in which CRP levels are typically lower than those observed in Western populations, was sparse. We examined the cross-sectional association between short- and long-term exposure to particulate matter and inflammatory markers, including high-sensitivity CRP (hs-CRP) and white blood cell (WBC) count, in a representative population of Japanese community dwellers (NIPPON DATA2010). We analysed data from 2360 participants (1002 men and 1358 women), aged 20 years or older, who resided in 300 randomly selected districts (222 public health centre areas) throughout Japan. We used background concentrations of suspended particulate matter (SPM, defined as particles with a 100% cut-off level at 10 μm aerodynamic diameter) and co-pollutants within the public health centre area. A logistic regression model was applied to estimate odds ratios (ORs) of elevated hs-CRP (> 0.3 mg/dl) or WBC (> 9000/μl). Since smoking is an important confounding factor, we firstly included this in the models, and additionally conducted the analyses after excluding current smokers. The one-month average concentration of SPM was positively associated with hs-CRP (OR per 10 μg/m3 increase in SPM = 1.42, 95% confidence interval = 1.00–2.04), and high exposure to SPM on the day of blood draw was associated with increased WBC count, after excluding current smokers (OR = 1.13, 1.01–1.28). Similar association patterns were observed for ozone. In conclusion, exposure to particulate matter was associated with inflammatory markers in the general Japanese population. Systemic inflammation may play a role in the link between particulate matter and cardiovascular disease.
Show more [+] Less [-]Are intertidal soft sediment assemblages affected by repeated oil spill events? A field-based experimental approach Full text
2016
Sandrini-Neto, Leonardo | Martins, César C. | Lana, Paulo C.
This study investigates the impact of repeated diesel spills on the structure of intertidal macrofaunal assemblages of a subtropical estuary. Three frequencies of exposure events were compared against two dosages of oil in a factorial experiment with asymmetrical controls. Hypotheses were tested to distinguish between (i) the overall effect of oil spills, (ii) the effect of diesel dosage via different exposure regimes, and (iii) the effect of time since last spill. Repeated oil spills dramatically altered the overall structure of assemblages and reduced the total density of macrofauna and densities of dominant taxa. Increasing the frequency of oil spills negatively affected macrofauna. In general, frequent low-dosage oil spills were more deleterious than infrequent high-dosage ones. However, increases in densities of some taxa, mainly the gastropod Heleobia australis, were observed in response to infrequent spills. Our results highlight the importance of repeated exposure events in determining the extent of oil impacts.
Show more [+] Less [-]Elevated CO2 increases glomalin-related soil protein (GRSP) in the rhizosphere of Robinia pseudoacacia L. seedlings in Pb- and Cd-contaminated soils Full text
2016
Jia, Xia | Zhao, Yonghua | Liu, Tuo | Huang, Shuping | Chang, Yafei
Glomalin-related soil protein (GRSP), which contains glycoproteins produced by arbuscular mycorrhizal fungi (AMF), as well as non-mycorrhizal-related heat-stable proteins, lipids, and humic materials, is generally categorized into two fractions: easily extractable GRSP (EE-GRSP) and total GRSP (T-GRSP). GRSP plays an important role in soil carbon (C) sequestration and can stabilize heavy metals such as lead (Pb), cadmium (Cd), and manganese (Mn). Soil contamination by heavy metals is occurring in conjunction with rising atmospheric CO2 in natural ecosystems due to human activities. However, the response of GRSP to elevated CO2 combined with heavy metal contamination has not been widely reported. Here, we investigated the response of GRSP to elevated CO2 in the rhizosphere of Robinia pseudoacacia L. seedlings in Pb- and Cd-contaminated soils. Elevated CO2 (700 μmol mol−1) significantly increased T- and EE- GRSP concentrations in soils contaminated with Cd, Pb or Cd + Pb. GRSP contributed more carbon to the rhizosphere soil organic carbon pool under elevated CO2 + heavy metals than under ambient CO2. The amount of Cd and Pb bound to GRSP was significantly higher under elevated (compared to ambient) CO2; and elevated CO2 increased the ratio of GRSP-bound Cd and Pb to total Cd and Pb. However, available Cd and Pb in rhizosphere soil under increased elevated CO2 compared to ambient CO2. The combination of both metals and elevated CO2 led to a significant increase in available Pb in rhizosphere soil compared to the Pb treatment alone. In conclusion, increased GRSP produced under elevated CO2 could contribute to sequestration of soil pollutants by adsorption of Cd and Pb.
Show more [+] Less [-]Source apportionment and health effect of NOx over the Pearl River Delta region in southern China Full text
2016
Lu, Xingcheng | Yao, Teng | Li, Ying | Fung, Jimmy C.H. | Lau, Alexis K.H.
As one of the most notorious atmospheric pollutants, NOx not only promotes the formation of ozone but also has adverse health effects on humans. It is therefore of great importance to study the sources of NOx and its effects on human health. The Comprehensive Air Quality Model (CAMx) modeling system and ozone source apportionment technology (OSAT) were used to study the contribution of NOx from different emission sources over southern China. The results indicate that heavy duty diesel vehicles (HDDVs) and industrial point sources are the two major local NOx sources, accounting for 30.8% and 18.5% of local NOx sources, respectively. In Hong Kong, marine emissions contributed around 43.4% of local NOx in 2011. Regional transport is another important source of this pollutant, especially in February and November, and it can contribute over 30% of ambient NOx on average. Power plant point emission is an significant regional source in Zhuhai, Zhongshan and Foshan. The total emission sources are estimated to cause 2119 (0–4405) respiratory deaths and 991 (0–2281) lung cancer deaths due to long-term exposure to NOx in the Pearl River Delta region. Our results suggest that local governments should combine their efforts and vigorously promote further reduction of NOx emissions, especially for those sources that make a substantial contribution to NOx emissions and affect human health: HDDV, LDGV, industrial point sources and marine sources.
Show more [+] Less [-]Estimating ground-level PM10 in a Chinese city by combining satellite data, meteorological information and a land use regression model Full text
2016
Meng, Xia | Fu, Qingyan | Ma, Zongwei | Chen, Li | Zou, Bin | Zhang, Yan | Xue, Wenbo | Wang, Jinnan | Wang, Dongfang | Kan, Haidong | Liu, Yang
Development of exposure assessment model is the key component for epidemiological studies concerning air pollution, but the evidence from China is limited. Therefore, a linear mixed effects (LME) model was established in this study in a Chinese metropolis by incorporating aerosol optical depth (AOD), meteorological information and the land use regression (LUR) model to predict ground PM10 levels on high spatiotemporal resolution. The cross validation (CV) R² and the RMSE of the LME model were 0.87 and 19.2 μg/m³, respectively. The relative prediction error (RPE) of daily and annual mean predicted PM10 concentrations were 19.1% and 7.5%, respectively. This study was the first attempt in China to estimate both short-term and long-term variation of PM10 levels with high spatial resolution in a Chinese metropolis with the LME model. The results suggested that the LME model could provide exposure assessment for short-term and long-term epidemiological studies in China.
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