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Olive mill waste biochar: a promising soil amendment for metal immobilization in contaminated soils
2015
Hmid, Amine | Al Chami, Ziad | Sillen, Wouter | De Vocht, Alain | Vangronsveld, Jaco
The potential use of biochar from olive mill waste for in situ remediation of metal contaminated soils was evaluated. Biochar was mixed with metal contaminated soil originating from the vicinity of an old zinc smelter. Soil–biochar mixtures were equilibrated for 30 and 90 days. At these time points, Ca(NO₃)₂exchangeable metals were determined, and effects of the biochar amendment on soil toxicity were investigated using plants, bacteria, and earthworms. Bean (Phaseolus vulgaris) growth, metal content, antioxidative enzymes activities, and soluble protein contents were determined. Furthermore, effects on soil microbial communities (activity, diversity, richness) were examined using Biolog ECOplates. After 120 days of soil–biochar equilibration, effects on weight and reproduction of Eisenia foetida were evaluated. With increasing biochar application rate and equilibration period, Ca(NO₃)₂exchangeable metals decreased, and growth of bean plants improved; leaf metal contents reduced, the activities of antioxidative stress enzymes decreased, and soluble protein contents increased. Soil microbial activity, richness, and diversity were augmented. Earthworm mortality lowered, and their growth and reproduction showed increasing trends.
Afficher plus [+] Moins [-]Body concentrations of persistent organic pollutants and prostate cancer: a meta-analysis
2015
Lim, Jung-eun | Park, Su Hyun | Jee, Sun Ha | Park, Hyesook
There have been some concerns that persistent organic pollutants (POPs) may be associated with the risk of prostate cancer. Meta-analyses have not yet investigated the association between human-biomonitoring data for POPs and prostate cancer risk. The purpose of this study was to assess the association between body concentration of individual compounds or mixtures of POPs and prostate cancer risk in the general population by performing a meta-analysis. A literature search was performed using PubMed, EMBASE, and KoreaMed from the period 1950 through 2014. The odds ratio (OR) and its 95 % confidence interval (CI) of prostate cancer associated with POPs were estimated using fixed-effects model or random-effects model where appropriate. Dose–response relationships were assessed by using the generalized least-squares method for trend estimation. A total of eight (six case–control, one cross-sectional, one nested case–control) studies including 1158 prostate cancer cases among 6932 subjects were selected for the meta-analysis. Total POPs of interest showed positive associations with statistical significance on prostate cancer (OR 1.31, 95 % CI 1.13, 1.57). In dose–response meta-analysis, 1 μg/g lipid of PCBs was found to be associated with a 49 % increased risk of prostate cancer (OR 1.49, 95 % CI 1.07, 2.06). One nanogram per gram (1000 μg/g) lipid of trans-nonachlor was found to be associated with approximately 2 % increased risk of prostate cancer (OR = 1.02/1 ng/g lipid of trans-nonachlor, 95 % CI 1.00, 1.03). The available evidence suggests that body concentrations of POPs are positively associated with prostate cancer risk, which implies valuable evidence for prostate cancer prevention.
Afficher plus [+] Moins [-]Polycyclic aromatic hydrocarbons associated with total suspended particles and surface soils in Kunming, China: distribution, possible sources, and cancer risks
2015
Yang, Xiaoxia | Ren, Dong | Sun, Wenwen | Li, Xiaoman | Huang, Bin | Chen, Rong | Lin, Zhan | Pan, Xuejun
The concentrations, distribution, possible sources, and cancer risks of polycyclic aromatic hydrocarbons (PAHs) in total suspended particles (TSPs) and surface soils collected from the same sampling spots were compared in Kunming, China. The total PAH concentrations were 9.35–75.01 ng/m³and 101.64–693.30 ng/g dry weight (d.w.), respectively, in TSPs and surface soils. Fluoranthene (FLA), pyrene (PYR), chrysene (CHR), and phenanthrene (PHE) were the abundant compounds in TSP samples, and phenanthrene (PHE), fluorene (FLO), fluoranthene (FLA), benzo[b]fluoranthene (BbF), and benzo[g,h,i]perylene (BghiP) were the abundant compounds in surface soil samples. The spatial distribution of PAHs in TSPs is closely related to the surrounding environment, which varied significantly as a result of variations in source emission and changes in meteorology. However, the spatial distribution of PAHs in surface soils is supposed to correlate with a city’s urbanization history, and high levels of PAHs were always observed in industry district, or central or old district of city. Based on the diagnostic ratios and principal component analysis (PCA), vehicle emissions (especially diesel-powered vehicles) and coal and wood combustion were the main sources of PAHs in TSPs, and the combustion of wood and coal, and spills of unburnt petroleum were the main sources of PAHs in the surface soils. The benzo[a]pyrene equivalent concentration (BaPₑq) for the TSPs and surface soil samples were 0.16–2.57 ng/m³and 11.44–116.03 ng/g d.w., respectively. The incremental lifetime cancer risk (ILCR) exposed to particulate PAHs ranged from 10⁻⁴to 10⁻³indicating high potential of carcinogenic risk, and the ILCR exposed to soil PAHs was from 10⁻⁷to 10⁻⁶indicating virtual safety. These presented results showed that particle-bound PAHs had higher potential carcinogenic ability for human than soil PAHs. And, the values of cancer risk for children were always higher than for adults, which demonstrated that children were sensitive to carcinogenic effects of PAHs.
Afficher plus [+] Moins [-]Determination of trace metal baseline values in Posidonia oceanica, Cystoseira sp., and other marine environmental biomonitors: a quality control method for a study in South Tyrrhenian coastal areas
2015
Conti, M. E. | Mecozzi, Mauro | Finoia, Maria Grazia
In this study, we investigated Cd, Cr, Cu, Pb, and Zn in the seagrass Posidonia oceanica (L.) Delile leaves and in the brown algae Cystoseira sp. sampled along a 280-km transect in the Tyrrhenian Sea, from the Ustica to Linosa Islands (Sicily, Italy) with the aim to determine their control charts (baseline levels). By applying the Johnson’s (Biometrika 36:149–175, 1949) probabilistic method, we determined the metal concentration overlap ranges in a group of five biomonitors. Here, we propose the use of the indexes of bioaccumulation with respect to the lowest (L′ᵢ) and the highest (Lᵢ) extreme values of the overlap metal concentration ranges. These indexes allow the identification of the most opportune organism (or a suite of them) to better managing particular environmental conditions. Posidonia leaves have generally high Lᵢindexes for Cd, Cu, Pb, and Zn, and this suggests its use as biomonitor for baseline marine areas. Our results confirm the high aptitude of Patella as a good biomonitor for Cd levels in seawater. From this study, Ustica resulted with higher levels of Cd, Cu, Pb, and Zn than the other Sicilian Islands.
Afficher plus [+] Moins [-]Controlled formation of reactive Fe particles dispersed in a carbon matrix active for the oxidation of aqueous contaminants with H2O 2
2015
Tristão, Juliana Cristina | de Mendonça, Fernanda Gomes | Lago, Rochel Montero | Ardisson, José Domingos
In this work, reactive iron nanoparticles dispersed in a carbon matrix were produced by the controlled thermal decomposition of Fe³⁺ions in sucrose. During the sucrose decomposition, the Fe³⁺ions are reduced to form iron nanometric cores dispersed in a porous carbonaceous matrix. The materials were prepared with iron contents of 1, 4, and 8 wt.% and heated at 400, 600, and 800 °C. Analyses by X-ray diffraction, Mössbauer spectroscopy, magnetization measurements, Raman spectroscopy, termogravimetric analyses, BET surface area, scanning, and transmission electron microscopy showed that at 400 °C, the materials are composed essentially of Fe₃O₄particles, while treatments at higher temperatures, i.e., 600 and 800 °C, produced phases such as Fe⁰and Fe₃C. The composites were tested for the oxidation of methylene blue with H₂O₂by a Fenton-type reaction and also H₂O₂decomposition, showing better performance for the material containing 8 % of iron heated at 400 and 600 °C. These results are discussed in terms of Fe²⁺surface species in the Fe₃O₄nanoparticles active for the Fenton reaction.
Afficher plus [+] Moins [-]The influence of the environmental management system on the environmental impact of seaport companies during an economic crisis: Lithuanian case study
2015
Anne, Olga | Burskyte, Vilma | Stasiškienė, Žaneta | Balciunas, Arunas
Freight handling in EU ports fell by more than 12 % during the global economic crisis in 2008–2009 after almost a decade of continuous growth. The decrease of freight handling in the Klaipeda seaport, the only port in Lithuania, was 6.7 % and happened due to the dominant outward movement of goods (mainly oil products). The Klaipeda seaport, due to its peculiarity, is the only ice-free port in the northern part of Baltic Sea. The present study explores the environmental impact of Klaipeda seaport activities from 2001 to 2011. Moreover, it compares the environmental effectiveness of environmental protection strategies used in the four biggest companies that, in fact, cover about 88 % of total activities (except general cargo) of the seaport. The first group of targeted companies used an environmental protection strategy to implement an ISO 14001-based environmental management system, and the second group selected to follow environmental management practices without certification. The paper analyses the development of the companies’ activities in regard to the change of environmental effectiveness. The paper evaluates the pressure of the economic crisis on the companies’ activities and its influence on environmental decisions, with particular interest in the ability of different environmental protection systems to resist and handle the expected performance. The study identified a significant decrease in companies’ activities during the crisis period. However, the economic activities and environmental effectiveness demonstrated similar short-term tendencies in regard to the environmental strategy selection but differed in long-term perspective.
Afficher plus [+] Moins [-]Contamination of commercially available seafood by key diarrhetic shellfish poisons along the coast of China
2015
Lin, Chao | Liu, Zeng-Shan | Tan, Cai-Yun | Guo, Yi-Ping | Li, Lin | Ren, Hong-Lin | Li, Yan-Song | Hu, Pan | Gong, Sheng | Zhou, Yu | Lu, Shi-Ying
With the increasing number of outbreaks of food-borne diseases caused by okadaic acid (OA) and its analogue dinophysistoxin-1 (DTX-1), two key diarrhetic shellfish poison (DSP) toxins, OA and DTX-1, have become a serious threat to public health and have attracted significant public attention in China. The aim of our study was to monitor OA and DTX-1 contamination in commercially available seafood and to provide references for tracking these toxins and preventing disease outbreaks. From 2010 to 2012, 40 species were collected from six coastal cities of four inland seas in China. An enzyme-linked immunosorbent assay (ELISA) and a lateral flow immunochromatographic (LFIC) test strip were used to analyse the samples, and the results were further confirmed using a commercially available ELISA kit. The monitoring results indicated that 23 of 40 species were positive for contamination. In addition, 14 of the positive species were determined to be inedible because the content of OA and DTX-1 was above the regulatory limit. Simultaneously, we verified that the digestive glands of shellfish tended to accumulate toxin, in contrast to the flesh. The highest concentrations of OA and DTX-1 were recorded in Scapharca broughtonii, which was collected from Qing Dao, in relation to the other analysed species. Moreover, the Arca family as well as Mytilus galloprovincialis were severely contaminated by OA and its analogue. The above results indicate that some of the commercially available seafood from the coastal cities in China may be inedible due to serious marine toxin contamination. The results of this study might play an important role in protecting consumer health and safety screening of marine products.
Afficher plus [+] Moins [-]Short-term exposure to low doses of rotenone induces developmental, biochemical, behavioral, and histological changes in fish
2015
Melo, Karina Motta | Oliveira, Rhaul | Grisolia, Cesar Koppe | Domingues, Inês | Pieczarka, Julio Cesar | de Souza Filho, José | Nagamachi, Cleusa Yoshiko
Rotenone, a natural compound derived from plants of the genera Derris and Lonchocarpus, is used worldwide as a pesticide and piscicide. This study aims to assess short-term toxicity of rotenone to early-life stages of the fish Danio rerio and Poecilia reticulata using a wide and integrative range of biomarkers (developmental, biochemical, behavioral, and histopathological). Moreover, the species sensitivity distribution (SSD) approach was used to compare rotenone acute toxicity to fish species. Toxicity tests were based on the OECD protocols, fish embryo toxicity test (for D. rerio embryos), and fish acute toxicity test (for P. reticulata juveniles). D. rerio embryos were used to estimate lethal concentrations and analyze embryonic and enzymatic alterations (activity of catalase, glutathione-S-transferase, and cholinesterase), while P. reticulata juveniles were used for the assessment of histological damage in the gills and liver. Rotenone induced significant mortality in zebrafish embryos with a 96-h lethal concentration 50 % (LC₅₀) = 12.2 μg/L. Rotenone was embryotoxic, affecting the development of D. rerio embryos, which showed cardiac edema; tail deformities; loss of equilibrium; and a general delay characterized by lack of tail detachment, delayed somite formation, yolk sac absorption, and lack of pigmentation. Biochemical biomarker inhibition was observed for concentrations ≥1 μg/L for CAT and glutathione-S-transferase (GST) and for cholinesterase (ChE) in concentration from 10 μg/L. Behavioral changes were observed for P. reticulata juveniles exposed to concentrations equal to or above 25 μg/L of rotenone; moreover, histological damage in the liver and gills of fish exposed to concentrations equal to or above 2.5 μg/L could be observed. A hazard concentration 5 % (HC₅) of 3.2 μg/L was estimated considering the acute toxicity data for different fish species (n = 49). Lethal and sublethal effects of rotenone raise a concern about its effects on nontarget fish species, especially because rotenone and its metabolite rotenolone are frequently reported in the microgram range in natural environments for several days after field applications. Rotenone should be used with caution. Given the high toxicity and wide range of sublethal effects here reported, further studies in a chronic exposure scenario are recommended.
Afficher plus [+] Moins [-]Comparison of the MBBR denitrification carriers for advanced nitrogen removal of wastewater treatment plant effluent
2015
Yuan, Quan | Wang, Haiyan | Hang, Qianyu | Deng, Yangfan | Liu, Kai | Li, Chunmei | Zheng, Shengzhi
The moving bed biofilm reactors (MBBRs) were used to remove the residual NO₃ ⁻-N of wastewater treatment plant (WWTP) effluent, and the MBBR carriers for denitrification were compared. The results showed that high denitrification efficiency can be achieved with polyethylene, polypropylene, polyurethane foam, and haydite carriers under following conditions: 7.2 to 8.0 pH, 24 to 26 °C temperature, 12 h hydraulic retention time (HRT), and 25.5 mg L⁻¹ external methanol dosage, while the WWTP effluent total nitrogen (TN) was between 2.6 and 15.4 mg L⁻¹ and NO₃ ⁻-N was between 0.2 and 12.6 mg L⁻¹. The MBBR filled with polyethylene carriers had higher TN and NO₃ ⁻-N removal rate (44.9 ± 19.1 and 83.4 ± 13.0 %, respectively) than those with other carriers. The minimum effluent TN and NO₃ ⁻-N of polyethylene MBBR were 1.6 and 0.1 mg L⁻¹, respectively, and the maximum denitrification rate reached 23.0 g m⁻² day⁻¹. When chemical oxygen demand (COD)/TN ratio dropped from 6 to 4, the NO₃ ⁻- N and TN removal efficiency decreased significantly in all reactors except for that filled with polyethylene, which indicated that the polyethylene MBBR can resist influent fluctuation much better. The three-dimensional excitation–emission matrix analysis showed that all the influent and effluent of MBBRs contain soluble microbial products (SMPs)-like organics and biochemical oxygen demand (BOD), which can be removed better by MBBRs filled with haydite and polyethylene carriers. The nitrous oxide reductase (nosZ)-based terminal restriction fragment length polymorphism (T-RFLP) analysis suggested that the dominant bacteria in polyethylene MBBR are the key denitrificans.
Afficher plus [+] Moins [-]Cytotoxicity, DNA damage, and apoptosis induced by titanium dioxide nanoparticles in human non-small cell lung cancer A549 cells
2015
Wang, Yurong | Cui, Haiyan | Zhou, Jiaping | Li, Fengjuan | Wang, Jinju | Chen, Mianhua | Liu, Qingdai
Concerns about the risk of titanium dioxide nanoparticles (TiO₂NPs) to human health and environment are gradually increasing due to their wide range of applications. In this study, cytotoxicity, DNA damage, and apoptosis induced by TiO₂NPs (5 nm) in A549 cells were investigated. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays revealed the time- and concentration-dependent cytotoxic effects of TiO₂NPs in a concentration range of 50 to 200 μg/mL. A statistically significant (p < 0.05) induction in DNA damage was observed by the comet assay in cells exposed to 50 to 200 μg/mL TiO₂NPs for 48 h. A significant (p < 0.05) induction in micronucleus formation determined by 4,6-diamino-2-phenylindole (DAPI) staining was also observed at the above concentrations. Typical apoptotic morphological feature and apoptotic bodies in A549 cells induced by TiO₂NPs at the above concentrations were observed by scanning electron micrographs. Flow cytometric analysis demonstrated that the cells treated with TiO₂NPs at concentrations of 100 and 200 μg/mL showed a significant G₂/M phase arrest and a significant increased proportion of apoptotic cells. TiO₂NPs also disrupted the mitochondrial membrane potential evaluated by rhodamine 123 staining. Further analysis by quantitative real-time PCR (qRT-PCR) indicated that the expression of caspase-3 and caspase-9 messenger RNA (mRNA) was increased significantly at the concentrations of 100 and 200 μg/mL TiO₂NPs for 48 h. Taken together, these findings suggest that TiO₂NPs can inhibit A549 cell proliferation, cause DNA damage, and induce apoptosis via a mechanism primarily involving the activation of the intrinsic mitochondrial pathway. The assay data provide strong evidence that TiO₂NPs can induce cytotoxicity, significant DNA damage, and apoptosis of A549 cells, suggesting that exposure to TiO₂NPs could cause cell injury and be hazardous to health.
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