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Long-term nickel exposure altered the bacterial community composition but not diversity in two contrasting agricultural soils
2015
Li, Jing | Hu, Hang-Wei | Ma, Yi-Bing | Wang, Jun-Tao | Liu, Yu-Rong | He, Ji-Zheng
Nickel pollution imposes deleterious effects on soil ecosystem. The responses of soil microorganisms to long-term nickel pollution under field conditions remain largely unknown. Here, we used high-throughput sequencing to elucidate the impacts of long-term nickel pollution on soil bacterial communities in two contrasting agricultural soils. Our results found that the soil microbial biomass carbon consistently decreased along the nickel gradients in both soils. Nickel pollution selectively favored or impeded the prevalence of several dominant bacterial guilds, in particular, Actinobacteria showed tolerance, while Acidobacteria and Planctomycetes displayed sensitivity. Despite the apparent shifts in the bacterial community composition, no clear tendency in the bacterial diversity and abundance was identified along the nickel gradients in either soil. Collectively, we provide evidence that long-term nickel pollution shifted the soil bacterial communities, resulting in the decrease of microbial biomass although the bacterial diversity was not significantly changed.
Show more [+] Less [-]Long-term exposure of rapeseed (Brassica napus L.) to ZnO nanoparticles: anatomical and ultrastructural responses
2015
Mousavi Kouhi, Seyed Mousa | Lahouti, Mehrdad | Ganjeali, Ali | Entezari, Mohammad H.
Rapid development of nanotechnology in recent years has raised concerns about nanoparticle (NPs) release into the environment and its adverse effects on living organisms. The present study is the first comprehensive report on the anatomical and ultrastructural changes of a variety of cells after long-term exposure of plant to NPs or bulk material particles (BPs). Light and electron microscopy revealed some anatomical and ultrastructural modifications of the different types of cell in the root and leaf, induced by both types of treatment. Zinc oxide (ZnO) BPs-induced modifications were surprisingly more than those induced by ZnO NPs. The modifications induced by ZnO BPs or ZnO NPs were almost similar to those induced by excess Zn. Zn content of the root and leaf of both ZnO NPs- and ZnO BPs-treated plants was severely increased, where the increase was greater in the plants treated with ZnO BPs. Overall, these results indicate that the modifications induced by ZnO particles can be attributed, at least partly, to the Zn²⁺ dissolution by ZnO particles rather than their absorption by root and their subsequent effects.
Show more [+] Less [-]Distinguishing anthropogenic and natural sources of trace elements in soils undergoing recent 10-year rapid urbanization: a case of Donggang, Eastern China
2015
Lv, Jianshu | Liu, Yang | Zhang, Zulu | Zhou, Rujia | Zhu, Yuchi
A total of 59 samples consisting of 45 topsoils samples and 14 subsoils samples were collected from urban soils of Donggang and were analyzed for soil properties and 12 trace elements. The mean contents of As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Se, V, and Zn in topsoils were 5.76, 0.20, 9.88, 44.82, 17.69, 0.05, 578.96, 19.98, 28.38, 0.21, 58.88, and 58.32 mg kg⁻¹, respectively. The mean enrichment factor results suggested that Hg, Cd, Pb, Cu, Se, and Zn were enriched in topsoils compared with subsoils. Spatial distribution maps of trace elements indicated that Hg, Cd, Pb, Cu, Se, and Zn had similar patterns, with the highest values in the industrial region. There were no significant associations displayed between spatial distributions of As, Co, Cr, Mn, Ni, and V and the industrial region. Through correlation analysis, stepwise regression analysis, and redundancy analysis, three main sources of 12 trace elements were identified. Cd, Hg, and Se originated from industrial emissions and coal combustion, and As, Co, Cr, Mn, Ni, and V had a lithogenic origin. The combination of human activities and natural sources contributed to the contents of Cu, Pb, and Zn, and the human activities included industrial and traffic emissions.
Show more [+] Less [-]Neighborhood epidemiological monitoring and adult mental health: European Quality of Life Survey, 2007–2012
2015
Shiue, Ivy
Little is monitored on perceived neighborhood noise, quality of drinking water, air quality, rubbish, traffic, etc. at a continental scale. This study was aimed to examine the relationships of such neighborhood risks and mental health in adults and the very old in an international and population-based setting across Europe. Data were retrieved from the European Quality of Life Survey, 2007–2012 including demographics, living conditions, income and financial situation, housing and local environment, family, work, health, social participation and quality of social services. Adults aged 18 and above were included for statistical analysis (n = 79,270). Analysis included chi-square test, t test and logistic regression modeling. People who lived in town or city tended to indicate certain major problems for them such as noise (odds ratio (OR) 2.34, 95 % confidence interval (CI) 2.17–2.53, P < 0.001), air quality (OR 2.76, 95 % CI 2.54–3.00, P < 0.001), low quality of drinking water (OR 1.33, 95 % CI 1.23–1.43, P < 0.001), crime and/or violence (OR 2.92, 95 % CI 2.68–3.19, P < 0.001), rubbish (OR 3.68, 95 % CI 3.41–3.97, P < 0.001) and traffic congestion (OR 2.64, 95 % CI 2.45–2.85, P < 0.001). People who reported major problems on noise (OR 2.19, 95 % CI 1.96–2.45, P < 0.001), air quality (OR 2.11, 95 % CI 1.87–2.37, P < 0.001), low quality of drinking water (OR 2.40, 95 % CI 2.14–2.68, P < 0.001), crime and/or violence (OR 2.13, 95 % CI 1.88–2.41, P < 0.001), rubbish (OR 1.98, 95 % CI 1.77–2.11, P < 0.001) and traffic congestion (OR 1.50, 95 % CI 1.34–1.68, P < 0.001) were also classified as having depression. Perceived neighborhood conditions were associated with adult mental health across Europe. Future neighborhood monitoring research moving from the etiological to neighborhood management would be suggested.
Show more [+] Less [-]Association between atmospheric pollutants and hospital admissions in Lisbon
2015
Cruz, A. M. J. | Sarmento, S. | Almeida, S. M. | Silva, A. V. | Alves, C. | Freitas, M. C. | Wolterbeek, H.
Ambient air pollution is recognised as one of the potential environmental risk factors causing health hazards to the exposed population, demonstrated in numerous previous studies. Several longitudinal, ecological and epidemiological studies have shown associations between outdoor levels of outdoor atmospheric pollutants and adverse health effects, especially associated with respiratory and cardiovascular hospital admissions. The aim of this work is to assess the influence of atmospheric pollutants over the hospital admissions in Lisbon, by Ordinary Least Squares Linear Regression. The pollutants (CO, NO, NO₂, SO₂, O₃, PM₁₀and PM₂.₅) were obtained from 13 monitoring stations of the Portuguese Environmental Agency, which provide hourly observations. Hospital admission data were collected from the Central Administration of the Health System and were compiled by age: <15, 15–64, >64 years old. The study period was 2006–2008. Results showed significant positive associations between the following: (1) the pollutants CO, NO, NO₂, SO₂, PM₁₀and PM₂.₅and circulatory diseases for ages between 15 and 64 years (0.5 % hospital admissions (HA) increase with 10 μg m⁻³NO increase) and above 64 years (1.0 % stroke admission increase with 10 μg m⁻³NO₂increase); (2) the pollutants CO, NO, NO₂, SO₂, PM₁₀and PM₂.₅and respiratory diseases for ages below 15 years (up to 1.9 % HA increase with 10 μg m⁻³pollutant increase); and (3) the pollutants NO, NO₂and SO₂and respiratory diseases for ages above 64 years (1.3 % HA increase with 10 μg m⁻³CO increase).
Show more [+] Less [-]Nucleoplasmic bridges and tailed nuclei are signatures of radiation exposure in Oreochromis mossambicus using erythrocyte micronucleus cytome assay (EMNCA)
2015
Anbumani, S. | Mohankumar, Mary N.
Gamma radiation-induced genetic perturbations in aquatic vertebrates is largely unknown at low-dose rate, especially in the wake of a nuclear disaster and/or other environmental outbreaks. Freshwater fish, Oreochromis mossambicus subjected to low-dose rate (2 mGy/min) at 2.5-, 5-, and 10-Gy doses, were analyzed for “exposure signatures” in blood samples drawn on days 3, 6, 12, 18, and 30, respectively. Significant dose-dependent increments in micronuclei frequency and other anomalies such as nucleoplasmic bridges and tailed nuclei were observed and exhibit a strong positive correlation, suggesting that they could be used as prospective signatures of radiation exposure. Similarly increased incidence of apoptosis and DNA repair machinery circuits at high and low doses were noted. This work highlighted “cytogenetic signatures” in fish and the sensitivity of these endpoints toward low-dose rate of radiation exposure.
Show more [+] Less [-]Novel approach for extinguishing large-scale coal fires using gas–liquid foams in open pit mines
2015
Lu, Xinxiao | Wang, Deming | Qin, Botao | Tian, Fuchao | Shi, Guangyi | Dong, Shuaijun
Coal fires are a serious threat to the workers’ security and safe production in open pit mines. The coal fire source is hidden and innumerable, and the large-area cavity is prevalent in the coal seam after the coal burned, causing the conventional extinguishment technology difficult to work. Foams are considered as an efficient means of fire extinguishment in these large-scale workplaces. A noble foam preparation method is introduced, and an original design of cavitation jet device is proposed to add foaming agent stably. The jet cavitation occurs when the water flow rate and pressure ratio reach specified values. Through self-building foaming system, the high performance foams are produced and then infused into the blast drilling holes at a large flow. Without complicated operation, this system is found to be very suitable for extinguishing large-scale coal fires. Field application shows that foam generation adopting the proposed key technology makes a good fire extinguishment effect. The temperature reduction using foams is 6–7 times higher than water, and CO concentration is reduced from 9.43 to 0.092 ‰ in the drilling hole. The coal fires are controlled successfully in open pit mines, ensuring the normal production as well as the security of personnel and equipment.
Show more [+] Less [-]Concentrations of trace elements in the kidney, liver, muscle, and skin of short sea snake (Lapemis curtus) from the Strait of Hormuz Persian Gulf
2015
Heydari Sereshk, Zahra | Riyahi Bakhtiari, Alireza
To our knowledge, this is the first report into trace elements accumulation in tissues of the short sea snake (Lapemis curtus). Lead (Pb), cadmium (Cd), copper (Cu), vanadium (V), nickel (Ni), and zinc (Zn) were determined in the kidney, liver, skin, and muscle tissues of short sea snake, L. curtus, from the Strait of Hormuz during October 2011. Skins generally displayed the lowest trace element burdens. Kidneys displayed the highest Pb, Cd, V, Ni, and Cu mean concentrations (0.89, 0.04, 1.66, 6.22, and 20.23 μg g⁻¹ dry weight, respectively), while muscle exhibited the highest Zn levels (493.32 μg g⁻¹ dry weight). Concentration ranges of the selected trace elements were compared with those reported in other studies. Data presented here may be considered as a baseline for further ecotoxicological studies in sea snakes.
Show more [+] Less [-]Microscopic biomineralization processes and Zn bioavailability: a synchrotron-based investigation of Pistacia lentiscus L. roots
2015
De Giudici, G. | Medas, D. | Meneghini, C. | Casu, M. A. | Gianoncelli, A. | Iadecola, A. | Podda, S. | Lattanzi, P.
Plants growing on polluted soils need to control the bioavailability of pollutants to reduce their toxicity. This study aims to reveal processes occurring at the soil-root interface of Pistacia lentiscus L. growing on the highly Zn-contaminated tailings of Campo Pisano mine (SW Sardinia, Italy), in order to shed light on possible mechanisms allowing for plant adaptation. The study combines conventional X-ray diffraction (XRD) and scanning electron microscopy (SEM) with advanced synchrotron-based techniques, micro-X-ray fluorescence mapping (μ-XRF) and X-ray absorption spectroscopy (XAS). Data analysis elucidates a mechanism used by P. lentiscus L. as response to high Zn concentration in soil. In particular, P. lentiscus roots take up Al, Si and Zn from the rhizosphere minerals in order to build biomineralizations that are part of survival strategy of the species, leading to formation of a Si-Al biomineralization coating the root epidermis. XAS analysis rules out Zn binding to organic molecules and indicates that Zn coordinates Si atoms stored in root epidermis leading to the precipitation of an amorphous Zn-silicate. These findings represent a step forward in understanding biological mechanisms and the resulting behaviour of minor and trace elements during plant-soil interaction and will have significant implications for development of phytoremediation techniques.
Show more [+] Less [-]Enhancements in nocturnal surface ozone at urban sites in the UK
2015
Kulkarni, Pavan S. | Bortoli, D. | Silva, A. M. | Reeves, C. E.
Analysis of diurnal patterns of surface ozone (O₃) at multiple urban sites in the UK shows the occurrence of prominent nocturnal enhancements during the winter months (November–March). Whilst nocturnal surface ozone (NSO) enhancement events have been observed at other locations, this is the first time that such features have been demonstrated to occur in the UK and the second location globally. The observed NSO enhancement events in the UK were found to be so prevalent that they are clearly discernible in monthly diurnal cycles averaged over several years of data. Long-term (2000–2010) analysis of hourly surface ozone data from 18 urban background stations shows a bimodal diurnal variation during the winter months with a secondary nighttime peak around 0300 hours along with the primary daytime peak. For all but one site, the daily maxima NSO concentrations during the winter months exceeded 60 μg/m³ on >20 % of the nights. The highest NSO value recorded was 118 μg/m³. During the months of November, December, and January, the monthly averaged O₃ concentrations observed at night (0300 h) even exceeded those observed in the daytime (1300 h). The analysis also shows that these NSO enhancements can last for several hours and were regional in scale, extending across several stations simultaneously. Interestingly, the urban sites in the north of the UK exhibited higher NSO than the sites in the south of the UK, despite their daily maxima being similar. In part, this seems to be related to the sites in the north typically having lower concentrations of nitrogen oxides.
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