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Periodic monitoring of persistent organic pollutants and molecular damage in Cyprinus carpio from Büyük Menderes River
2017
Çağdaş, Beste | Kocagöz, Rasih | Onat, İlgen | Perçin, Fatih | Özaydın, Okan | Orhan, Hilmi
Concentrations of persistent organic pollutants (POPs) were quantified in river water and sediment, as well as in the liver and muscle tissues of Cyprinus carpio that were sampled four times in a year at three stations in the Büyük Menderes River (BMR). Potential biomarkers of possible cellular molecular damage, namely lipid peroxidation (LPO) degradation products, protein carbonyls (PCO) and DNA repair product 8-hydroxy-2′-deoxyguanosine (8-OHdG), were analysed. All the targeted pollutants were measurable both in biotic and abiotic samples. Interestingly, the results suggested that there was recent organochlorine pesticide (OCP) input into the river water in the first two sampling periods in all stations in contrast to prohibition, while input of polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs) was not detected. Liver POP concentrations were higher than in muscle, as expected, and were found to decrease from the first to the fourth sampling period in all stations, except PBDEs. Levels of LPO degradation products in the liver and in muscle tissues decreased from the first to the fourth sampling period. This suggests that these markers reflect the lipid damage in respective tissues due to the tissue burden of targeted POPs. Protein carbonyls were the highest in the first sampling period, followed by a dramatic decrease in the second, and then a gradual increase towards the fourth sampling period in all stations. 8-OHdG levels were lower in Sarayköy station in the first sampling period. Among the measured biomarkers, only several LPO degradation products were significantly correlated with OCPs and PCBs in liver tissue.
Afficher plus [+] Moins [-]The effects of aquaculture on mercury distribution, changing speciation, and bioaccumulation in a reservoir ecosystem
2017
Liang, Peng | Feng, Xinbin | You, Qiongzhi | Gao, Xuefei | Xu, Jialin | Wong, Minghung | Christie, Peter | Wu, Sheng-Chun
A survey was conducted in a freshwater reservoir located in Guizhou province, south China, to investigate the influence of fish aquaculture activities on mercury (Hg) distribution, speciation change, and bioaccumulation. Water, sediment, and aquaculture fish samples were collected from aquaculture sites (AS) and the corresponding reference sites (RS). The results showed that total mercury (THg) concentration in overlying water in Wujiangdu reservoir reached 6.87 ± 14.9 ng L⁻¹. THg concentration in a different layer follows the sequence: surface layer > bottom layer > three intermediate layers with significant difference. In addition, the total methylmercury (TMeHg) concentration in overlying water was 0.113 ± 0.211 ng L⁻¹. The highest TMeHg was observed in the bottom layer. Both dissolved Hg (DHg) and dissolved methylmercury (DMeHg) accounted for more than 50% of THg and TMeHg in the top four layers of overlying water, respectively. In contrast, particulate Hg (PHg) and particulate methylmercury were the major portion of THg and TMeHg in bottom layer and reached to 67 and 58.7% of THg and TMeHg, respectively. Aquaculture activities were estimated to contribute an annual loading of approximately 69.8 ng g⁻¹of THg yearly in the top 1 cm of sediment underneath the rafts due to unconsumed fish feed. The extra loading of THg in sediment may have potential to stimulate the release of Hg to the overlying water. Both DMeHg and DHg in sediment pore water and organic matter (OM) contents in the top 4 cm of AS were noticeably higher than RS, which indicated that the accumulation of OM due to aquaculture activities promoted MeHg production in the top surface of sediment pore water. No significant difference was noted between THg in RS (296 ± 104 ng g⁻¹) and AS (274 ± 132 ng g⁻¹) in the solid phase. In addition, the sediments were net sources of both MeHg and inorganic Hg. For Hg in fish tissues, THg and inorganic Hg (IHg) in the liver were significantly higher (THg: p < 0.001, F = 9.98; IHg: p < 0.001, F = 13.1) than those in the other organs. In contrast, MeHg concentration in the muscle was significantly higher than (p < 0.01, F = 4.83) that in the other organs.
Afficher plus [+] Moins [-]Retrospective biomonitoring of mercury and other elements in museum feathers of common kestrel Falco tinnunculus using instrumental neutron activation analysis (INAA)
2017
Movalli, Paola | Bode, Peter | Dekker, René | Fornasari, Lorenzo | van der Mije, Steven | Yosef, Reuven
This study examines the potential to use instrumental neutron activation analysis (INAA) to explore temporal and geographical variation in exposure to heavy metals and other selected elements in common kestrel Falco tinnunculus using feathers from a natural history collection. The study gathered samples of two breast feathers from each of 16 adult male kestrel specimens from Naturalis Biodiversity Centre, collected in The Netherlands between 1901 and 2001. Feather samples were analysed for more than 50 elements, using INAA at the Reactor Institute Delft. Results (in mg/kg dw) were transformed into ratios of milligram of element per millimetre of feather length. The distribution of the mass fractions and ratios was plotted for each element against time and by geographical area. Observed mass fractions and/or ratios are discussed for selected elements (Hg, Cd, Zn, Pt, Pd, Se, Al, Rb, As, Sb, Cr, V, Cl, Br) known to have, at certain concentrations, adverse effects on raptors. Some samples show mass fractions of certain elements (Cr, Cd, Se, As) above levels known to have adverse effects. We conclude that the analysis of museum feathers using INAA provides reference values for concentrations of selected elements, including those of high societal concern such as Hg and Cd, against which to assess concentrations of these elements in feathers of present-day living raptor populations.
Afficher plus [+] Moins [-]Distribution and human health risk assessment of PAHs in four fish species from a SW Atlantic estuary
2017
Oliva, Ana L. | La Colla, Noelia S. | Arias, Andrés H. | Blasina, Gabriela E. | Lopez Cazorla, Andrea | Marcovecchio, Jorge E.
The aim of this study is to assess—for the first time—the concentration of the 16 polycyclic aromatic hydrocarbons (PAHs) in the muscle tissues of four fish species (Micropogonias furnieri, Cynoscion guatucupa, Ramnogaster arcuata, and Mustelus schmitti) from Bahía Blanca estuary, Argentina and to evaluate their sources, distribution, and the human health risks implicated. Considering the four species under study, mean total PAH concentrations showed the following decreasing accumulation trend: M. schmitti, R. arcuata, C. guatucupa, and M. furnieri. Low molecular weight PAHs, such as naphthalene and phenanthrene, were generally predominant, displaying properties of PAH mixtures generated from petrogenic pollution. Of the four fish species analyzed, M. furnieri was the only one that did not raise any human consumption warning. In the case of the other species, exceeding values were found above the safety human consumption guidelines. Nevertheless, the screening criteria for carcinogenic PAHs proposed by the USEPA indicated a good quality status for these fish species.
Afficher plus [+] Moins [-]Ecological risk assessment of heavy metals in salt-affected soils in the Natura 2000 area (Ciechocinek, north-central Poland)
2017
Bartkowiak, Agata | Lemanowicz, Joanna | Hulisz, Piotr
This paper aimed to evaluate the ecological risk posed by the accumulation of heavy metals in the salt-affected soils of the habitat covered by the EU Natura 2000 program in relation to the activity of soil redox enzymes. The research was carried out in the halophyte reserve in Ciechocinek (north-central Poland) which is a very specific habitat as it undergoes a long-term human impact related to both the operation of the medical spa town and the agricultural use of soils in the adjacent areas. The obtained results showed that the content of Zn, Cu, Pb, and Cd in the studied soils exceeded the Polish standards. Based on the obtained data and statistical analysis, it was found that metals may come from two different sources: emission from household boiler rooms (Pb, Cd) and corroded brine sewage pipeline (Zn, Cu).They are characterized by limited mobility due to alkaline environment and strong sorption properties of the clay fraction and organic matter. The correlation analysis indicates that the dehydrogenase activities were negatively correlated with soil electrical conductivity (EC₁:₅) (r = − 0.665, P < 0.05). Taking into account the protective status of the area, it is difficult to indicate definitely the solution concerning the land management. However, according to the authors, one should pay special attention to a possibility of using halophytes which occur within the reserve for phytoremediation.
Afficher plus [+] Moins [-]Impact of socio-demographic factors on the mitigating actions for climate change: a path analysis with mediating effects of attitudinal variables
2017
Masud, MuhammadMehedi | Akhatr, Rulia | Nasrin, Shamima | Adamu, IbrahimMohammed
Socio-demographic factors play a significant role in increasing the individual’s climate change awareness and in setting a favorable individual attitude towards its mitigation. To better understand how the adversative effects of climate change can be mitigated, this study attempts to investigate the impact of socio-demographic factors on the mitigating actions of the individuals (MAOI) on climate change. Qualitative data were collected from a face-to-face survey of 360 respondents in the Kuala Lumpur region of Malaysia through a close-ended questionnaire. Analysis was conducted on the mediating effects of attitudinal variables through the path model by using the SEM. Findings indicate that the socio-demographic factors such as gender, age, education, income, and ethnicity can greatly influence the individual’s awareness, attitude, risk perception, and knowledge of climate change issues. The results drawn from this study also revealed that the attitudinal factors act as a mediating effect between the socio-demographic factors and the MAOI, thereby, indicating that both the socio-demographic factors and the attitudinal factors have significant effects on the MAOI towards climate change. The outcome of this study can help policy makers and other private organizations to decide on the appropriate actions to take in managing climate change effects. These actions which encompass improving basic climate change education and making the public more aware of the local dimensions of climate change are important for harnessing public engagement and support that can also stimulate climate change awareness and promote mitigating actions to n protect the environment from the impact of climate change.
Afficher plus [+] Moins [-]Level, source identification, and risk analysis of heavy metal in surface sediments from river-lake ecosystems in the Poyang Lake, China
2017
Zhang, Hua | Jiang, Yinghui | Ding, Mingjun | Xie, Zhenglei
The concentrations, sources, and risks of heavy metals (Fe, Al, Mn, Cr, Co, Ni, Cu, Zn, As, Cd, W, Pb, and Tl) in sediments in five river-lake ecosystems in the Poyang Lake region were studied. The concentrations of the heavy metals varied spatially, with most of the highest concentrations in the Raohe river-lake ecosystem (RH). All heavy metals except As, Cd, W, and Tl were enriched in sediments possessing high total organic carbon contents or in finer sediments. Based on enrichment factors and statistical methods, it was found that Cd in sediments in the Xiushui (XS), Ganjiang (GJ), Xinjiang (XJ) river-lake ecosystems, and RH; Mn in the XS, GJ, and RH; and W in the XS and GJ were greatly affected by anthropogenic inputs. Moreover, the origins of Cu, Zn, and As require more attention due to the high concentrations found. The high enrichment factor of Cd in the sediments indicated that this metal might cause significant pollution in the environment. The results of the modified potential ecological risk index revealed that the XS, GJ, RH, and XJ were at considerable ecological risk, while the sediments in the Fuhe river-lake ecosystem (FH) were at moderate ecological risk, with Cd contributing the highest proportion of risk. The hazard score fundamentally validated the modified potential ecological risk analysis and revealed a mean toxicity of 57.80% to the benthic organisms in the RH.
Afficher plus [+] Moins [-]Chemical characterization of diesel and hydrotreated vegetable oil (HVO) soot after reactive gas probing using diffuse reflectance FTIR spectroscopy (DRIFTS)
2017
Tapia, A. | Salgado, M. S. | Martín, M. P. | Rodríguez-Fernández, J. | Rossi, M. J. | Cabañas, B.
A chemical characterization of diesel and hydrotreated vegetable oil (HVO) soot has been developed using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) before and after the reaction with different probe gases. Samples were generated under combustion conditions corresponding to an urban operation mode of a diesel engine and were reacted with probe gas-phase molecules in a Knudsen flow reactor. Specifically, NH₂OH, O₃ and NO₂ were used as reactants (probes) and selected according to their reactivities towards specific functional groups on the sample surface. Samples of previously ground soot were diluted with KBr and were introduced in a DRIFTS accessory. A comparison between unreacted and reacted soot samples was made in order to establish chemical changes on the soot surface upon reaction. It was concluded that the interface of diesel and HVO soot before reaction mainly consists polycyclic aromatic hydrocarbons, nitro and carbonyl compounds, as well as ether functionalities. The main difference between both soot samples was observed in the band of the C=O groups that in diesel soot was observed at 1719 cm⁻¹ but not in HVO soot. After reaction with probe gases, it was found that nitro compounds remain on the soot surface, that the degree of unsaturation decreases for reacted samples, and that new spectral bands such as hydroxyl groups are observed.
Afficher plus [+] Moins [-]Lactational exposure to abamectin induced mortality and adverse biochemical and histopathological effects in suckling pups
2017
Mossa, Abdel-Tawab H. | Abdel Rasoul, Mona A. | Mohafrash, Samia M. M.
Information about the adverse effects of lactation transfer of abamectin (ABA) is important for human health, especially in the third-world countries where breastfeeding is the only source of nutrition for infants. So, the present study was undertaken to evaluate the adverse effects of breastfeeding exposure to ABA on oxidative damage and liver and kidney dysfunction in suckling rats. Dams were orally administered ABA at a doses 22.10, 11.05, and 2.21 mg a.i./kg b.wt from postnatal day 1 (PND1) until day 20 (PND20). The signs of toxicity and high mortality were recorded in suckling male (67.5%) and female (55.0%) pups whose mother exposed to the ABA at dose 22.1 mg a.i./kg b.wt. ABA induced significantly decrease in body weights of mothers and their male and female pups and significant increase in relative liver weights. It caused oxidative stress in the liver and kidney of mothers and their pups by increasing the level of malondialdehyde (MDA) and decreased activities of superoxide dismutase (SOD) and glutathione-transferase (GST). ABA altered the level of serum liver and kidney dysfunction biomarkers either in the mothers or their male and female pups in a dose-dependent manner. It caused histopathological alterations in the liver and kidney tissues. It can be decided that ABA was accumulated in mother’s milk, transferred through breast feeding, and induced mortality in their suckling pups. It caused oxidative stress, lipid peroxidation, and biochemical and histopathological alterations in the liver and kidney of mothers and their suckling pups. The results in the present study add some information about the adverse effect of lactation transfer of ABA, which is important for human health in the third-world countries where breastfeeding may be the only source of nutrition for infants in the first and most critical weeks of life.
Afficher plus [+] Moins [-]Effect of forestry-waste biochars on adsorption of Pb(II) and antibiotic florfenicol in red soil
2017
Jiang, Canlan | Cai, Hao | Chen, Lulu | Chen, Liwei | Cai, Tianming
Biochars derived from Pinus massoniana and Cunninghamia lanceolata trunks (abbreviated as PB and CB, respectively) were used to investigate their potential capabilities to improve lead (Pb(II)) and antibiotic florfenicol (FLO) immobilization in soil. Results shows that, after incubation for 60 days, the maximum adsorption capacities (Q ₘ) of biochar-treated soils (soil-PB and soil-CB) for Pb(II) was increased by 27 and 14 %, respectively, compared with pristine soil sample. In the case of FLO, however, the Q ₘ of biochar-treated soils were enhanced by 266 and 206 % for soil-PB and soil-CB, respectively. The increased Pb(II) adsorption was mainly due to the enhanced interactions between Pb(II) and oxygen-containing functional groups and aromatic structures in biochars. Whereas, the improvement of FLO adsorption was achieved through electrostatic interaction, hydrogen bonding, and van der Waals forces interactions between FLO molecule and biochars. Regardless of the similarities in chemical compositions between two biochars, significantly higher surface area and total pore volume of PB than CB biochar may be the key factors accounting for the differences in adsorption efficiencies for Pb(II) and FLO between Soil-PB and Soil-CB.
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