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An endocrine disruptor, bisphenol A, affects development in the protochordate Ciona intestinalis: Hatching rates and swimming behavior alter in a dose-dependent manner
2013
Matsushima, Ayami | Ryan, Kerrianne | Shimohigashi, Yasuyuki | Meinertzhagen, Ian A.
Bisphenol A (BPA) is widely used industrially to produce polycarbonate plastics and epoxy resins. Numerous studies document the harmful effects caused by low-dose BPA exposure especially on nervous systems and behavior in experimental animals such as mice and rats. Here, we exposed embryos of a model chordate, Ciona intestinalis, to seawater containing BPA to evaluate adverse effects on embryonic development and on the swimming behavior of subsequent larvae. Ciona is ideal because its larva develops rapidly and has few cells. The rate of larval hatching decreased in a dose-dependent manner with exposures to BPA above 3 μM; swimming behavior was also affected in larvae emerging from embryos exposed to 1 μM BPA. Adverse effects were most severe on fertilized eggs exposed to BPA within 7 h post-fertilization. Ciona shares twelve nuclear receptors with mammals, and BPA is proposed to disturb the physiological functions of one or more of these.
Afficher plus [+] Moins [-]Mycorrhizal colonization affects the elemental distribution in roots of Ni-hyperaccumulator Berkheya coddii Roessler
2013
Orłowska, Elżbieta | Przybyłowicz, Wojciech | Orlowski, Dariusz | Mongwaketsi, Nametso P. | Turnau, Katarzyna | Mesjasz-Przybyłowicz, Jolanta
The effect of arbuscular mycorrhizal fungi (AMF) on the distribution and concentration of elements in roots of Ni-hyperaccumulating plant Berkheya coddii was studied. Micro-PIXE (particle-induced X-ray emission) analysis revealed significant differences between AMF-inoculated and non-inoculated plants as well as between main and lateral roots. The accumulation of P, K, Mn and Zn in the cortical layer of lateral roots of inoculated plants confirmed the important role of AMF in uptake and accumulation of these elements. Higher concentration of P, K, Fe, Ni, Cu and Zn in the vascular stele in roots of AMF-inoculated plants than in the non-inoculated ones indicates more efficient translocation of these elements to the aboveground parts of the plant. These findings indicate the necessity of including the influence of AMF in studies on the uptake of elements by plants and in industrial use of B. coddii for Ni extraction from polluted soils.
Afficher plus [+] Moins [-]Soil contamination by phthalate esters in Chinese intensive vegetable production systems with different modes of use of plastic film
2013
Wang, Jun | Luo, Yongming | Teng, Ying | Ma, Wenting | Christie, Peter | Li, Zhengao
The concentrations of six priority phthalic acid esters (PAEs) in intensively managed suburban vegetable soils in Nanjing, east China, were analyzed using gas chromatography–mass spectrometry (GC–MS). The total PAE concentrations in the soils ranged widely from 0.15 to 9.68 mg kg−1 with a median value of 1.70 mg kg−1, and di-n-butyl phthalate (DnBP), bis-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) were the most abundant phthalate esters. Soil PAE concentrations depended on the mode of use of plastic film in which PAEs were incorporated as plasticizing agents and both the plastic film and poultry manure appeared to be important sources of soil PAEs. Vegetables in rotation with flooded rice led to lower concentrations of PAEs in soil. The results indicate that agricultural plastic film can be an important source of soil PAE contamination and further research is required to fully elucidate the mechanisms of PAE contamination of intensive agricultural soils with different use modes of use of plastic film.
Afficher plus [+] Moins [-]Developmental effects of aerosols and coal burning particles in zebrafish embryos
2013
Olivares, Alba | van Drooge, Barend L. | Casado, Marta | Prats, Eva | Serra, Montserrat | van der Ven, Leo T. | Kamstra, Jorke H. | Hamers, Timo | Hermsen, Sanne | Grimalt, Joan O. | Piña, Benjamin
Embryo toxicity of particles generated by combustion processes is of special concern for human health. A significant part of these toxic effects is linked to the binding of some pollutants (like polycyclic aromatic hydrocarbons or PAHs) to the Aryl hydrocarbon Receptor (AhR) and the activation of target genes, like the cytochrome P4501A. This activity was analyzed for ambient air and coal-combustion particle extracts in zebrafish embryos (the cyp1aDarT assay) and in two single-cell bioassays: the yeast-based YCM-RYA and the DR-luc (rat cells) assay. Observed AhR ligand activity of samples generally correlated to the predicted toxic effect according to their PAH composition, except for one of the coal combustion samples with an anomalously high activity in the cyp1aDarT assay. This sample induced deformities in zebrafish embryos. We concluded that the combination of morphological and molecular assays may detect embryonic toxic effects that cannot be predicted from chemical analyses or single-cell bioassays.
Afficher plus [+] Moins [-]Reclamation of copper-contaminated soil using EDTA or citric acid coupled with dissolved organic matter solution extracted from distillery sludge
2013
Liu, Zhengzhong | Lin, Ying-Chen
Soil washing using a strong chelating agent is a common practice for restoring contaminated soils, but significant soil fertility degradation and high operation costs are the major disadvantages. Washing soil with a dissolved organic matter (DOM) solution has been identified as a method that can moderate the loss of nutrients in the soil and enhance metal removal. The DOM solutions were extracted from waste sludge obtained from a local whisky distillery. Single chelating washing and chelate-DOM washing were carried out using ethylenediaminetetraacetic acid (EDTA), citric acid, and DOM solutions to remediate highly Cu-contaminated soil. Two-phase washing using 0.34 M citric acid and then 1500 mg L−1 DOM solution (pH 8.5) was found to be most favorable for the soil. With this treatment, 91% Cu was removed from the topsoil; the organic matter, cation exchange capacity, plant-available nitrogen, and available phosphate content increased by 28.1%, 103%, 17.7%, and 422%, respectively.
Afficher plus [+] Moins [-]Global assessment of the effects of terrestrial acidification on plant species richness
2013
Azevedo, Ligia B. | van Zelm, Rosalie | Hendriks, A Jan | Bobbink, Roland | Huijbregts, Mark A.J.
This study estimates the potential losses of vascular plant species richness due to terrestrial acidification for different world's biomes. We used empirical occurrence data of 2409 species from 140 studies and estimated the relative species richness – pH response curves using logistic regressions. The regressions were then used to quantify the fraction of species that are potentially lost due to soil pH changes. Although we found considerable variability within biomes, out results show that the pH at which species richness was maximized was found to be the lowest in (sub)tropical forests (pH = 4.1) and the highest in deserts (pH = 7.4). We also found that (sub)tropical moist forests are highly sensitive to decreases of in soil pH below 4.1. This study can be coupled with existing atmospheric deposition models to quantify the risk of species richness loss following soil acidification.
Afficher plus [+] Moins [-]Extreme precipitation appears a key driver of mercury transport from the watershed to Cottage Grove Reservoir, Oregon
2013
Curtis, Lawrence R. | Morgans, Donna L. | Thoms, Bryn | Villenueve, Daniel
An abandoned cinnabar mining and roasting site is in the major sub-basin of the watershed for Cottage Grove Reservoir, Oregon. Average surface sediment total mercury concentration in the river draining this sub-basin (0.61 ± 0.52 μg/g) was about ten-fold higher than three smaller tributaries to the reservoir. Total mercury in reservoir surface sediments averaged 1.66 ± 0.70 μg/g. Stratigraphy for two sediment cores indicated generally decreased reservoir mercury loading from 1963 to 2002 but two pronounced peaks in mercury deposition. Years of extreme precipitation immediately prior to these peaks at least partially explained them. Epaxial muscle total mercury concentrations of largemouth bass increased with body weight up to 2.5 μg/g. A gradient of mercury concentrations in soils from a 3.3 km diameter grid indicated condensation of mercury vapors from the mine site polluted the sub-basin.
Afficher plus [+] Moins [-]The use of biodiesel blends on a non-road generator and its impacts on ozone formation potentials based on carbonyl emissions
2013
Chai, Ming | Lu, Mingming | Liang, Fuyan | Tzillah, Aisha | Dendramis, Nancy | Watson, Libya
In this study, emissions of carbonyl compounds from the use B50 and B100 were measured with a non-road diesel generator. A total of 25 carbonyl compounds were identified in the exhaust, including 10 with laboratory-synthesized standards. Formaldehyde, acetaldehyde, and acrolein were found as the most abundant carbonyl compounds emitted for both diesel and biodiesel. The sulphur content of diesel fuels and the source of biodiesel fuels were not found to have a significant impact on the emission of carbonyl compounds. The overall maximum incremental reactivity (MIR) was the highest at 0 kW and slightly increased from 25 to 75 kW. The MIR of B100 was the highest, followed by diesel and B50, which is consistent with the emission rates of total carbonyl compounds. This suggests that the use of biodiesel blends may be more beneficial to the environment than using pure biodiesel.
Afficher plus [+] Moins [-]Effects of soil pollutants, biogeochemistry and microbiology on the distribution and composition of enchytraeid communities in urban and suburban holm oak stands
2013
Rota, Emilia | Caruso, Tancredi | Monaci, Fabrizio | Baldantoni, Daniela | De Nicola, Flavia | Iovieno, Paola | Bargagli, Roberto
Holm oaks form typical urban woodlands in the Mediterranean region. We aimed at characterizing the enchytraeid communities in these environments and searching for possible correlations with soil parameters, including the traffic contamination. Samples of litter and topsoil were collected at different spatial scales and seasons in Naples and Siena cities and in two suburban stands. Only the co-variation between pollution and other soil chemico-physical factors showed significant effects, whereas no direct effect of soil microbiology was detected. Some thermophilous Fridericia and Achaeta tolerate high concentrations of heavy metals and PAHs and their abundance was mainly determined by Ca bioavailability. Central-European mesophilous species increased significantly under more temperate environmental conditions. Different combinations of soil cohesiveness, grain size composition and moisture regime seem to select species of certain body sizes.
Afficher plus [+] Moins [-]Status of metal accumulation in farmland soils across China: From distribution to risk assessment
2013
Niu, Lili | Yang, Fangxing | Xu, Chao | Yang, Huayun | Liu, Weiping
Increasing metal pollution has drawn broad public attention in China due to severe environmental quality deterioration. However, so far, there has been no study to survey metal accumulation in Chinese farmland soil at the national scale. In this study, we determined 11 metals in farmland soils across the Mainland China. Our results indicated the concentrations of Pb, Cd, Zn, and Cu (10.1–184.2, 0.082–1.31, 20.2–321.9, 8.2–515.9 mg/kg, respectively) were elevated above their reference values. Moreover, these metals followed a similar geochemical distribution pattern. The accumulation of Pb, Cd, Zn, and Cu in soils may be associated with human activities for soil fertility. Cadmium had the highest pollution index (PI) of 5.28, and the average hazard quotients (HQs) for all the metals were below 1. Hence, except for Cd, the metals in Chinese arable soils are comparatively safe. Results from this study may provide valuable information for agricultural soil management in China.
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