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1.
The hydrocarbon composition of atmospheric particulate matter from A Coruña city (Northwest Spain) has been studied. TSP (total suspended particulate) and PM10 (particulate matter with aerodynamic diameter <10 µm) samples were taken over 7 and 4 months at two stations located in residential and industrial sectors of A Coruña city, respectively. The levels of hydrocarbons found in atmospheric particulate samples of A Coruña city are higher than the ones found in other cities over the world. Ratios between the analysed compounds and their sources were established. Both anthropogenic and biogenic origins were found.  相似文献   

2.
Abstract

The effects of cadmium and lead on chronic mercury accumulation were investigated in O. aureus. After 140 days’ exposure the accumulation of mercury in the liver, brain, gill filaments, intestine, caudal muscle, spleen, trunk kidney and eye was analysed. The exposure concentrations were 0.05, 0.10 and 0.20 mg/L for mercury alone. O. aureus was also exposed to mixtures of 0.05 mg/L mercury with lead (0.05 mg/L and 0.50 mg/L or cadmium (0.05 mg/L) and 0.10 mg/L mercury with 0.10 mg/L cadmium. In food fish, a knowledge of toxic metal accumulation patterns is of great importance because of their contribution to the human diet and, as fishmeal, to the diet of agricultural animals. The trunk kidney consistently accumulated higher concentrations of mercury than any of the other tissues investigated.  相似文献   

3.
Elutriate embryo-larval bioassays with sea-urchins (Paracentrotus lividus) and ascidians (Ciona intestinalis) were conducted concurrently with trace metal analyses as part of an integrative assessment of sediment pollution at Ría de Pontevedra (Galicia, NW Spain). High metal contents in sediments were found in localised areas from the inner part of the estuary indicating a clear anthropogenic influence. In particular, very high Cu, Zn and Pb levels were found at sites P2 and P3, which were also the most toxic to the embryo-larval bioassays. Sediment quality guidelines were used to help in the ecological interpretation of sediment chemistry data and to identify pollutants of concern. Cu and Zn in P3 were consistently above the effects range median (ERM) values, which seem to be good predictors of toxicity to sea-urchin and ascidian embryos. A toxic unit approach, based on published EC(50) values and metal levels in elutriates, was used to assess the harmful ecological effects associated to sediment chemistry. Toxicity detected in P3 may be explained on the basis of the toxic unit model; however, the high toxicity detected at P2 may be attributable not only to the metals quantified in the analyses but also to unmeasured organic pollutants. Multidimensional scaling applied independently to the toxicology and chemistry data resulted in a good agreement between both types of configurations. Moreover, the Mantel test revealed a significant correlation (r(M)=0.481; p=0.019) between metal concentrations and toxicity data profiles, supporting the correspondence between configurations.  相似文献   

4.
Concentrations of Fe, Mn, Ni, Cu, Cr and Zn in their total, silicate, organic, reactive and pyrite fractions were determined in soils collected from the Ortigueira saltmarshes (Esteiro, Ladrido and Mera, NW Iberian Peninsula), from sediments of the Landoi and Esteiro Rivers, and from sludge generated by a nearby dunite mine. The Esteiro saltmarsh presented clear enrichments of the four metals studied (first 10 cm), especially of Ni and Cr, whose concentrations were among the highest. It is proposed that the elevated Cr and Ni levels found in the Esteiro saltmarsh were derived from recent contributions of the mine, which are partially discharged into the Landoi River. Total Cu and Zn concentrations were lower than the corresponding ones for Cr and Ni. Under suboxic conditions, Ni, Cr, Cu and Zn were mainly associated with the reactive fraction. Under anoxic conditions, Cu and Ni were associated mainly with the pyrite phase. Pyritic Zn and Cr concentrations were relatively low and similar in all three saltmarshes; however, where anoxic-sulfidic conditions prevailed these two metals were mainly associated with the reactive and organic fractions.  相似文献   

5.
Soil contamination with anthropogenic metals resulting from biosolid application is widespread around the world. To better predict the environmental fate and mobility of contaminants, it is critical to study the capacity of biosolid-amended soils to retain and release metals. In this paper, nickel adsorption onto a calcareous soil, a lime-stabilized biosolid, and soil–biosolid mixtures (30, 75, and 150 t biosolid/ha) was studied in batch experiments. Sorption experiments showed that (1) Ni adsorption was higher onto the biosolid than the calcareous soil, and (2) biosolid acted as an adsorbent in the biosolid–soil mixtures by increasing Ni retention capacity. The sorption tests were complemented with the estimation of Ni adsorption reversibility by successive applications of extraction solutions with water, calcium (100 mg/L), and oxalic acid (equivalent to 100 mg carbon/L). It has been shown that Ni desorption rates in soil and biosolid-amended soils were lower than 30 % whatever the chemical reagent, indicating that Ni was strongly adsorbed on the different systems. This adsorption/desorption hysteresis effect was particularly significant at the highest biosolid concentration (150 t/ha). Finally, an adsorption empirical model was used to estimate the maximum permissible biosolid application rate using French national guideline. It has been shown that desorption effects should be quantitatively considered to estimate relevant biosolid loadings.  相似文献   

6.
Valuable metal materials can be recovered from spent nickel–metal hydride (NiMH) batteries. However, little attention has been paid to the metal compositions of individual components of NiMH batteries, although this is important for the selection of the appropriate recycling process. In this study, NiMH batteries were manually disassembled to identify the components and to characterize the metals in each of these. A preliminary economic analysis was also conducted to evaluate the recovery of valuable metals from spent NiMH batteries using thermal melting versus simple mechanical separation. The results of this study show that metallic components account for more than 60% of battery weight. The contents of Ni, Fe, Co, and rare earth elements (REEs) (i.e., valuable metals of interest for recovery) in a single battery were 17.9%, 15.4%, 4.41%, and 17.3%, respectively. Most of the Fe was in the battery components of the steel cathode collector, cathode cap, and anode metal grid, while Ni (>90%) and Co (>90%) were mainly in the electrode active materials (anode and cathode metal powders). About 1.88 g of REEs (Ce, La, and Y) could be obtained from one spent NiMH battery. The estimated profits from recovering valuable metals from spent NiMH batteries by using thermal melting and mechanical processes are 2,329 and 2,531 USD/ton, respectively, when including a subsidy of 1,710 USD/ton. The findings of this study are very useful for further research related to technical and economic evaluations of the recovery of valuable metals from spent NiMH batteries. Implications: The spent nickel–metal hydride (NiMH) batteries were manually disassembled and their components were identified. The metals account for more than 60% of battery weight, when Ni, Fe, Co, and rare earth elements (REEs) were 17.9%, 15.4%, 4.41%, and 17.3%, respectively, in a single battery. The estimated profits of recovering valuable metals from NiMH batteries by using thermal melting and mechanical processing are 2,329 and 2,531 USD/ton, respectively, when including a subsidy of 1,710 USD/ton. These findings are very useful to develop or select the recovery methods of valuable metals from spent NiMH batteries.  相似文献   

7.
Ozone concentrations were measured at two (urban and a rural) sites near the city of Málaga (Spain). The aim of this study was to determine the daily, monthly and seasonal variation patterns of ozone concentrations at both sites and to study the possible regional influences. The daily variations mostly have the usual features with the afternoon maximum and the night minimum being more pronounced in the urban area. The average monthly concentrations throughout the year start to increase in March reaching their maximum values in July for the urban site. However, in the rural area, the monthly variations are smaller reaching their maximum value in June. The hourly evolution of the ozone concentrations in both sampling sites is well defined in spring and summer and not so well defined in autumn and winter. Taking into account the four seasons, the rural concentrations are higher than the urban ones. Summer is the season when there are similar concentrations at both sampling sites. Average hourly summer afternoon ozone for the hours 12:00-20:00 LST exceeded the 110 microg m(-3) European Union guidelines for human health for 8 h ozone exposure at the urban and rural sites.  相似文献   

8.
9.
The results of an interdisciplinary research program on the subsurface persistence and transport of pathogenic bacteria and viruses are evaluated on the basis of an expanded advection-dispersion model which considers the persistence of these microorganisms under the conditions found within an aquifer, the retardation by adsorption-desorption processes and the role of filtration processes. The model indicates that the principal controls are filtration processes, the microorganisms being fixed on the filter media are ultimately eliminated or inactivated by biological, chemical and physical processes.  相似文献   

10.
Total mercury (Hg), monomethylmercury (MeHg), and selenium (Se) were determined in blood of 11 bird species living in Doñana National Park (DNP, Southwestern Spain) and the surrounding area in 1999 and 2000 after a mine spill accident. The total Hg contents found varied from 1.00 to 587 ng/mL, with an MeHg percentage higher than 80 %, except in mallard species. In all the cases, the concentrations found were below the threshold of high risk for the bird populations. The parameters which most affected the accumulation of Hg and MeHg in the birds studied were, first, species, or trophic position, and second sampling area. Age does not seem to have a great influence on the content of Hg in the blood of these birds. The levels of Se found ranged from 108 to 873 ng/mL, and they were not affected by species, trophic level, age, or sampling area. The blood Hg concentrations of birds living in the area directly affected by the toxic mud, outside the park, were higher than those found in the other birds, and this could be explained by the mine spill accident happened in 1998.  相似文献   

11.
To seasonally evaluate littoral contamination, toxicity and quality values of sediments from the Gulf of Cádiz, we measured chemical concentrations and conducted toxicity tests in winter and summer and linked these results by means of multivariate analysis. Sediment samples were subjected to two separate, replicated sediment toxicity tests (Microdeutopus gryllotalpa amphipod survival, and Ruditapes philippinarum clam reburial), and to comprehensive sediment chemistry analyses (grain size, organic carbon, 14 heavy metals, and the surfactant linear alkylbenzenesulfonate (LAS)). Only sediments associated with an untreated urban discharge were toxic and related to high levels of surfactant LAS, Ag, and Pb. Multivariate analysis indicated that variables and chemicals associated with geochemical matrix and background levels (specific surface, Fe, Zn, Cu, V, Ni, and Co), chemicals associated with untreated urban discharge sources, and toxicity effects showed no seasonal variability. Only copper concentrations showed seasonal differences, being toxic during the winter and not toxic during summer. Multivariate analysis permits us to derive sediment quality values (SQVs); in terms of concentrations at or below which biological effects were not measured (mg kg(-1) dry sediment), are: LAS, 2.6; lead, 66.8; silver, 0.78; copper, 69.6.  相似文献   

12.

Purpose  

Perfluorinated compounds (PFCs) are widely distributed from industrialized to remote locations throughout the world. This study demonstrates the spatial distributions of PFCs in water and sediments from the L’Albufera Natural Park (Valencia, Spain).  相似文献   

13.
We report the evaluation of changes in water quality, increasing pollution level, of a section of Suquía River basin (Córdoba, Argentina) by using Myriophyllum quitense as bioindicator in addition to the measurement of chemical parameters, combined with chemometrics (ANOVA, Cluster and Discriminant Analysis). Myriophyllum quitense was collected upstream from Córdoba city at an unpolluted site of Suquía River basin. After collection plants were transplanted to different sites with different pollution levels. Subsequent to transplantation plants were weekly collected from the original site as well as from transplantation stations. Water quality was evaluated throughout the transplantation experiment, while the use of this macrophyte as bioindicator was verified through the activation of its antioxidant defenses and biotransformation system. Myriophyllum quitense reacts to the pollution stress increasing the activity of glutathione-S-transferases (CDNB and Fluorodifen), glutathione reductase (GR) and peroxidase (POD). Elevated enzyme activities agreed to different pollution levels, especially inorganic nitrogen loads combined with elevated lead and aluminum concentrations, all of them originated by anthropogenic activities, thus presenting Myriophyllum quitense as a good biomonitor for assessment of water quality in this polluted aquatic ecosystem.  相似文献   

14.
This study, based on a greenhouse pot culture experiment conducted with 15-day-old rapeseed (Brassica campestris L. cv. Pusa Gold; family Brassicaceae) and moong bean (Vigna radiata L. Wilczek cv. Pusa Ratna; family Fabaceae) plants treated with cadmium (Cd) concentrations (0, 50, and 100 mg kg?1 soil), investigates their potential for Cd accumulation and tolerance, and dissects the underlying basic physiological/biochemical mechanisms. In both species, plant dry mass decreased, while Cd concentration of both root and shoot increased with increase in soil Cd. Roots harbored a higher amount of Cd (vs. shoot) in B. campestris, while the reverse applied to V. radiata. By comparison, root Cd concentration was higher in B. campestris than in V. radiata. The high Cd concentrations in B. campestris roots and V. radiata shoots led to significant elevation in oxidative indices, as measured in terms of electrolyte leakage, H2O2 content, and lipid peroxidation. Both plants displayed differential adaptation strategies to counteract the Cd burden-caused anomalies in their roots and shoots. In B. campestris, increasing Cd burden led to a significantly decreased reduced glutathione (GSH) content but a significant increase in activities of GSH reductase (GR), GSH peroxidase (GPX), and GSH sulfotransferase (GST). However, in V. radiata, increasing Cd burden caused significant increase in GSH content and GR activity, but a significant decline in activities of GPX and GST. Cross talks on Cd burden of tissues and the adapted Cd tolerance strategies against Cd burden-accrued toxicity indicated that B. campestris and V. radiata are good Cd stabilizer and Cd extractor, respectively, wherein a fine tuning among the major components (GR, GPX, GST, GSH) of the GSH redox system helped the plants to counteract differentially the Cd load-induced anomalies in tissues. On the whole, the physiological/biochemical characterization of the B. campestris and V. radiata responses to varying Cd concentrations can be of great help in elaborating the innovative plant-based remediation technologies for metal/metalloid-contaminated sites.  相似文献   

15.
Environmental Science and Pollution Research - The study used scattered literature to summarize the effects of excess Cd, As, and Pb from contaminated soils on plant secondary metabolites/bioactive...  相似文献   

16.
In order to achieve sustainable development in agriculture, it is necessary to quantify and compare the energy, economic, and environmental aspects of products. This paper studied the energy, economic, and greenhouse gas (GHG) emission patterns in broiler chicken farms in the Alborz province of Iran. We studied the effect of the broiler farm size as different production systems on the energy, economic, and environmental indices. Energy use efficiency (EUE) and benefit-cost ratio (BCR) were 0.16 and 1.11, respectively. Diesel fuel and feed contributed the most in total energy inputs, while feed and chicks were the most important inputs in economic analysis. GHG emission calculations showed that production of 1000 birds produces 19.13 t CO2-eq and feed had the highest share in total GHG emission. Total GHG emissions based on different functional units were 8.5 t CO2-eq per t of carcass and 6.83 kg CO2-eq per kg live weight. Results of farm size effect on EUE revealed that large farms had better energy management. For BCR, there was no significant difference between farms. Lower total GHG emissions were reported for large farms, caused by better management of inputs and fewer bird losses. Large farms with more investment had more efficient equipment, resulting in a decrease of the input consumption. In view of our study, it is recommended to support the small-scale broiler industry by providing subsidies to promote the use of high-efficiency equipment. To decrease the amount of energy usage and GHG emissions, replacing heaters (which use diesel fuel) with natural gas heaters can be considered. In addition to the above recommendations, the use of energy saving light bulbs may reduce broiler farm electricity consumption.  相似文献   

17.
Environmental Science and Pollution Research - Water stored in open-pit lakes can be a water resource when the mine is closed. This study aimed to develop a reliable model to evaluate the water...  相似文献   

18.
This study reports a combined method using solid phase extraction (SPE), followed by solid phase microextraction (SPME) to concentrate different pesticides, including chlorinated, organophosphorus, triazines, pyretroids and chloroacetamides, present at trace levels in water samples. Identification and quantification was carried out by gas chromatography coupled to Mass Spectrometry (GC–MS). The optimized methodology showed LOQs at ng L?1 levels (ranging 0.2–3.5 ng L?1) in addition to acceptable precision and robustness (recoveries ranged 63–104%, RSD from 4% to 23%), presenting a novel method to reach trace levels, similar to that obtainable using EC detector, with structural confirmation by MS during the analysis of a wide range of environmental pollutants.This method was applied to the study of temporal and spatial distribution of pesticides in the Suquía River basin (Córdoba-Argentina). As expected, highest levels of agrochemicals were observed in areas with intensive agricultural practices, being atrazine (max. = 433.9 ng L?1), alpha-cypermetrine (max. = 121.7 ng L?1) and endosulfan sulfate (max. = 106.7 ng L?1) predominant. In urban areas, the prevalent pesticide was alpha-cypermethrine. These results draw attention to the need of pesticide monitoring programs in rivers, considering both urban and rural sections.  相似文献   

19.
Environmental Science and Pollution Research - Oxidation of Cr(III) by birnessite (δ-MnO2) was an important geochemical reaction determining the toxicity and mobility of dissolved Cr(III) in...  相似文献   

20.
Environmental Science and Pollution Research - The toxic metal lead (Pb) can be harmful to human health in various manners, but is also considered as a distinguished tracer of environmental...  相似文献   

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