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The chemistry and toxicity of discharge waters from copper mine tailing impoundment in the valley of the Apuseni Mountains in Romania 全文
2017
Rzymski, Piotr | Klimaszyk, Piotr | Marszelewski, Włodzimierz | Borowiak, Dariusz | Mleczek, Mirosław | Nowiński, Kamil | Pius, Bożena | Niedzielski, Przemysław | Poniedziałek, Barbara
Copper mining generates large quantities of waste, tailings, and acid outflows causing long-term environmental impacts and potential threats to human health. Valea Şesei is the largest tailing impoundment in Romania, created by flooding the valley (known as Valea Şesei) of the Metalliferous Mountains (a division of the Apuseni Mountains) with copper mining waste. The present study (i) estimated the total volume of tailings in this area; (ii) screened the concentration of 65 elements (rare earth and platinum group elements, alkali metals and alkali earth metals, transition and post-transition metals and metalloids) and cyanide concentrations in wastewater samples collected from tailing impoundment; (iii) evaluated the toxicity of these water samples using five in vitro bioassays employing human cells isolated from healthy donors and a short-term (1 h) exposure model. The sampled waters were highly acidic (pH 2.1–4.9) and had high electrical conductivity (280–1561 mS cm⁻¹). No cyanides were detected in any sample. Water samples collected from the stream (AMD) inflowing to the tailing impoundment were characterized by the greatest concentrations of alkali metals, alkaline earth metals, transition and post-transition metals, metalloids, rare earth elements, and noble metal group. At other sites, the elemental concentrations were lower but remained high enough to pose a relevant risk. The greatest magnitude of in vitro toxic effects was induced by AMD. Observed alterations included redox imbalance in human neutrophils followed by lipid peroxidation and decreased cell survival, significant aggregation of red blood cells, and increased prothrombin time. The study highlights that Valea Şesei is a large sink for toxic elements, posing environmental and health risks, and requiring action to prevent further release of chemicals and to initiate restoration of the area.
显示更多 [+] 显示较少 [-]Occurrence and distribution of six selected endocrine disrupting compounds in surface- and groundwaters of the Romagna area (North Italy) 全文
2017
Pignotti, Emanuela | Farré, Marinella | Barceló, Damià | Dinelli, Enrico
Endocrine disrupting compounds (EDCs) are a wide group of contaminants of emerging concern known to be harmful for organisms. The aim of the study was to assess the occurrence and distribution of six EDCs (estrone—E1, ß-estradiol—E2, 17α-ethinylestradiol—EE2, bisphenol A—BPA, perfluooctanoic acid—PFOA, perfluorooctane sulfonate—PFOS) in the Apenninic rivers and groundwaters of the Romagna area (North of Italy). Groundwaters were unaffected by EDC contamination, while all classes of compounds were detected at concentrations above the method quantification limit (MQL) in the majority of the river bodies. In detail, PFOA and PFOS concentrations varied between <MQL and 17.7 ng/l (PFOA) and between <MQL and 5.5 ng/l (PFOS), and their occurrence in the aquatic compartment was related to the discharge of wastewater treatment plant effluents. Concerning estrogens, EE2 was below the MQL in all samples, whereas E1 and E2 reached concentrations up to 39.7 ng/l (E2) and 28 ng/l (E1) in surface waters. The highest estrogen values were registered in those areas where livestock and farming are the main activities, indicating a close relation between these activities and estrogen release into the aquatic compartment. BPA (<MQL–171.3 ng/l) distribution in river waters did not show any correlation with a specific anthropic activity; a mixture of sources of contamination (e.g., industries of food packaging and plastic production) is rather responsible for its detection in river bodies. Overall, the northern part of the Romagna area showed a higher contamination by EDCs, in contrast with the southern part, which was almost unaffected by this kind of microcontamination.
显示更多 [+] 显示较少 [-]Phytotoxicity of CeO2 nanoparticles on radish plant (Raphanus sativus) 全文
2017
Gui, Xin | Rui, Mengmeng | Song, Youhong | Ma, Yuhui | Rui, Yukui | Zhang, Peng | He, Xiao | Li, Yuanyuan | Zhang, Zhiyong | Liu, Liming
Cerium oxide nanoparticles (CeO₂ NPs) have been considered as one type of emerging contaminants that pose great potential risks to the environment and human health. The effect of CeO₂ NPs on plant-edible parts and health evaluation remains is necessary and urgently to be developed. In this study, we cultivated radish in Sigma CeO₂ NP (<25 nm)-amended soils across a series of concentration treatments, i.e., 0 mg/kg as the control and 10, 50, and 100 mg/kg CeO₂ NPs. The results showed that CeO₂ NPs accelerated the fresh biomass accumulation of radish plant; especially in the treatment of 50 mg/kg CeO₂ NPs, root expansion was increased by 2.2 times as much as the control. In addition, the relative chlorophyll content enhanced by 12.5, 12.9, and 12.2% was compared to control on 40 cultivation days. CeO₂ NPs were mainly absorbed by the root and improved the activity of antioxidant enzyme system to scavenge the damage of free radicals in radish root and leaf. In addition, this study also indicated that the nanoparticles might enter the food chain through the soil into the edible part of the plant, which will be a potential threat to human health.
显示更多 [+] 显示较少 [-]Traffic aerosol lobar doses deposited in the human respiratory system 全文
2017
Manigrasso, Maurizio | Vernale, Claudio | Avino, Pasquale
Aerosol pollution in urban environments has been recognized to be responsible for important pathologies of the cardiovascular and respiratory systems. In this perspective, great attention has been addressed to Ultra Fine Particles (UFPs < 100 nm), because they efficiently penetrate into the respiratory system and are capable of translocating from the airways into the blood circulation. This paper describes the aerosol regional doses deposited in the human respiratory system in a high-traffic urban area. The aerosol measurements were carried out on a curbside in downtown Rome, on a street characterized by a high density of autovehicular traffic. Aerosol number-size distributions were measured by means of a Fast Mobility Particle Sizer in the range from 5.6 to 560 nm with a 1 s time resolution. Dosimetry estimates were performed with the Multiple-Path Particle Dosimetry model by means of the stochastic lung model. The exposure scenario close to traffic is represented by a sequence of short-term peak exposures: about 6.6 × 10¹⁰ particles are deposited hourly into the respiratory system. After 1 h of exposure in proximity of traffic, 1.29 × 10¹⁰, 1.88 × 10¹⁰, and 3.45 × 10¹⁰ particles are deposited in the head, tracheobronchial, and alveolar regions. More than 95 % of such doses are represented by UFPs. Finally, according to the greater dose estimated, the right lung lobes are expected to be more susceptible to respiratory pathologies than the left lobes.
显示更多 [+] 显示较少 [-]Association of breast adipose tissue levels of polychlorinated biphenyls and breast cancer development in women from Chaoshan, China 全文
2017
He, Yuanfang | Peng, Lin | Huang, Yiteng | Peng, Xiaodong | Zheng, Shukai | Liu, Caixia | Wu, Kusheng
Polychlorinated biphenyls (PCBs) are implied to be potential risk factors for breast cancer in wildlife and in in vivo and in vitro studies. Epidemiological studies revealed some individual or groups of PCB congeners associated with breast cancer risk, but consistent conclusions are scarce. This study aimed to explore the association between PCB exposure and breast cancer development. Breast adipose tissues were collected, and seven PCB congeners were analyzed by gas chromatography–mass spectrometry (GC-MS). Demographic characteristics, basic clinical data, and pathological diagnosis information were obtained from medical records. The differences in PCB exposure levels among different groups and indices were compared, and the correlation among PCB congeners was evaluated. The order of congener profile by molar concentration was PCB-153 > PCB-138 > PCB-180 > PCB-118 > PCB-101 > PCB-52 > PCB-28. ∑PCB level differed by occupation and residence and was significantly higher at 55–59-year-old group than at the other age groups. ∑PCB level was higher in postmenopausal than in premenopausal women. Decreasing ∑PCB levels were related with increasing parity among women with progesterone receptor (PR)-positive breast tumors. With increased clinical stage, the ∑PCB level increased significantly. ∑PCB level did not differ by tumor–node–metastasis classification and PR or human epidermal growth factor receptor 2 (HER2) expression but did differ by estrogen receptor (ER) expression (P = 0.04) without a regularly increasing trend in breast adipose tissue. These results suggest a potential association between PCB exposure and breast cancer development. Further in vitro and in vivo studies are needed to confirm these findings and explain the underlying mechanisms. Graphical Abstract Total PCBs level among different clinical stages in breast cancer patients
显示更多 [+] 显示较少 [-]Polybrominated diphenyl ethers in articles: a review of its applications and legislation 全文
2017
Jinhui, Li | Yuan, Zhen | Wenjing, Xiao
Polybrominated diphenyl ethers (PBDEs), especially commercial decabrominated diphenyl ethers (c-decaBDE), have been widely produced and applied to numerous materials because of their highly effective flame-retardant capabilities. The production of commercial pentaBDE (c-pentaBDE) and commercial octaBDE (c-octaBDE) ended in 2004 because they are persistent, bioaccumulative, and toxic to both humans and the environment, but decaBDE production and use continue. Furthermore, many congeners of PBDEs are still prevalent in consumer products and articles that they pose enormous threat to both the environment and human health. PBDEs have been detected in the casing of electrical and electronic equipment, textile materials, automotive interiors, polyurethane foam (PUF) in seat cushions, children’s toys, kitchenware, and other products. With increasing evidence about PBDE pollution and the adoption of international conventions, many developed countries have drawn more public attention to PBDEs and developed sound strategies for their management. This review summaries the utilization and management of PBDEs in a number of countries and reaches the conclusion that PBDEs are still prevalent in consumer articles, while specific regulations or policies for articles containing PBDEs are rare. Public awareness should be raised on the importance of sound management of articles containing PBDEs.
显示更多 [+] 显示较少 [-]Ozone alters the feeding behavior of the leaf beetle Agelastica coerulea (Coleoptera: Chrysomelidae) into leaves of Japanese white birch (Betula platyphylla var. japonica) 全文
2017
Agathokleous, Evgenios | Sakikawa, Tetsuichi | Abu ElEla, Shahenda A. | Mochizuki, Tomoki | Nakamura, Masahiro | Watanabe, Makoto | Kawamura, Kimitaka | Koike, Takayoshi
High mixing ratios of ground-level O₃ threaten trophic interactions. In the present study, we conducted laboratory assays, where insect larvae and adults were not directly exposed to O₃, to test the feeding behavior and attraction of the coleopteran leaf beetle Agelastica coerulea to early and late leaves of Japanese white birch (Betula platyphylla var. japonica) treated with ambient or elevated O₃ levels. We found that overwintered adults were not deterred from grazing elevated O₃-treated leaves, but rather preferred them than ambient O₃-treated ones. We also found that the feeding behavior of 2nd instar larvae fed on early or late leaves was not influenced by the O₃ treatment of the leaves when larvae could choose leaves. These observations of the adults and larvae feeding preferences contradict prior observations in the field conditions where the insects avoided leaves in O₃-enriched atmosphere. Since adults preferred elevated O₃-exposed leaves in the present laboratory assays, it is worthy of further investigations whether adults change their grazing preference so as to ensure the leaf palatability as a feeding source for their larvae. Hence, new direction towards detailed ovipositional behavior surveys under field conditions is encouraged.
显示更多 [+] 显示较少 [-]Enhanced Fenton-like degradation of TCE in sand suspensions with magnetite by NTA/EDTA at circumneutral pH 全文
2017
Wang, Na | Jia, Daqing | Jin, Yaoyao | Sun, Sheng-Peng | Ke, Qiang
The present study investigated the degradation of trichloroethylene (TCE) in sand suspensions by Fenton-like reaction with magnetite (Fe₃O₄) in the presence of various chelators at circumneutral pH. The results showed that ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) greatly improved the rate of TCE degradation, while [S,S]-ethylenediaminedisuccinic acid (s,s-EDDS), malonate, citrate, and phytic acid (IP6) have minimal effects on TCE degradation. Quenching tests suggested that TCE was mainly degraded by hydroxyl radical (HO·) attack, with about 90% inhibition on TCE degradation by the addition of HO· scavenger 2-propanol. The presence of 0.1–0.5% Fe₃O₄/sand (w/w) contributed to 40% increase in TCE degradation rates. In particular, the use of chelators can avoid high concentrations of H₂O₂ required for the Fenton-like reaction with Fe₃O₄, and moreover improve the stoichiometric efficiencies of TCE degradation to H₂O₂ consumption. The suitable concentrations of chelators (EDTA and NTA) and H₂O₂ were suggested to be 0.5 and 20 mM, respectively. Under the given conditions, degradation rate constants of TCE were obtained at 0.360 h⁻¹ with EDTA and 0.526 h⁻¹ with NTA, respectively. Enhanced degradation of TCE and decreased usage of H₂O₂ in this investigation suggested that Fenton-like reaction of Fe₃O₄ together with NTA (or EDTA) may be a promising process for remediation of TCE-contaminated groundwater.
显示更多 [+] 显示较少 [-]Occurrence of heavy metals and radionuclides in sediments and seawater in mangrove ecosystems in Pattani Bay, Thailand 全文
2017
Kaewtubtim, Pungtip | Meeinkuirt, Weeradej | Seepom, Sumalee | Pichtel, John
Mangrove ecosystems in Pattani Bay, Thailand are considered representatives for monitoring the occurrence of anthropogenic and natural pollution due to metal and radionuclide contamination. Sediments and seawater were collected from five locations to determine metal (Cd, Cr, Cu, Mn, Ni, Zn, and Pb) and radionuclide (²²⁶Ra, ²³²Th, and ⁴⁰K) concentrations. Spatial variations in metal and radionuclide concentrations were determined among the sampling sites. A geoaccumulation index (I gₑₒ) and enrichment factor (EF) were used to classify the impacts of metals from anthropogenic point sources. Significant values for I gₑₒ and EF were measured for Pb in site 4 (I gₑₒ 0.65; EF 28.2) and Cd in site 1 (I gₑₒ 1.48; EF 46.2). EF values in almost all sampling sites were >1 which indicates anthropogenic pollution. To assess the potential public hazard of radioactivity, the average radium equivalent activity (Raₑq), the external hazard index (H ₑₓ), the internal hazard index (H ᵢₙ), the absorbed dose rate in air (D), and the annual effective outdoor dose rate (E) were determined. Based on these measurements, it is concluded that the probability of human health risk from radionuclides is low. However, the absorbed dose in air (D) values in sites 4 and 5 were greater than the global average value of 55 nGy h⁻¹, indicating that sediments in these locations pose a radiological hazard. The data obtained in this study provides useful information on metal and radionuclide background levels in mangrove sediments and seawater, and can be applied toward human health risk assessment and metal and radionuclide mapping.
显示更多 [+] 显示较少 [-]Solid-phase extraction of multi-class pharmaceuticals from environmental water samples onto modified multi-walled carbon nanotubes followed by LC-MS/MS 全文
2017
Lalović, Bojana | Đurkić, Tatjana | Vukčević, Marija | Janković-Častvan, Ivona | Kalijadis, Ana | Laušević, Zoran | Laušević, Mila
In this paper, pristine and chemically treated multi-walled carbon nanotubes (MWCNTs) were employed as solid-phase extraction sorbents for the isolation and enrichment of multi-class pharmaceuticals from the surface water and groundwater, prior to liquid chromatography-tandem mass spectrometry analysis. Thirteen pharmaceuticals that belong to different therapeutical classes (erythromycin, azithromycin, sulfamethoxazole, diazepam, lorazepam, carbamazepine, metoprolol, bisoprolol, enalapril, cilazapril, simvastatin, clopidogrel, diclofenac) and two metabolites of metamizole (4-acetylaminoantipyrine and 4-formylaminoantipyrine) were selected for this study. The influence of chemical treatment on MWCNT surface characteristics and extraction efficiency was studied, and it was shown that HCl treatment of MWCNT leads to a decrease in the amount of surface oxygen groups and at the same time favorably affects the efficiency toward extraction of selected pharmaceuticals. After the optimization of the SPE procedure, the following conditions were chosen: 50 mg of HCl-treated MCWNT as a sorbent, 100 mL of water sample at pH 6, and 15 mL of the methanol-dichloromethane mixture (1:1, v/v) as eluent. Under optimal conditions, high recoveries (79–119%), as well as low detection (0.2 to 103 ng L⁻¹) and quantitation (0.5–345 ng L⁻¹) limits, were obtained. The optimized method was applied to the analysis of five surface water and two groundwater samples, and three pharmaceuticals were detected, the antiepileptic drug carbamazepine and two metabolites of antipyretic metamizole.
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