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1.
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   

2.
Zaal Kikvidze  Gigi Tevzadze 《Ambio》2015,44(5):452-457
Reports of the damage from wolf attacks have increased considerably over the last decade in Georgia (in the Caucasus). We interviewed locals about this problem in two focal regions: the Lanchkhuti area (in western Georgia) and Kazbegi District (in eastern Georgia) where livestock numbers had increased by an order of magnitude owing to dramatic shifts in the local economies over the last decade. This coincided with expanding habitats for wolves (abandoned plantations, for example). We found that the perceived damage from wolves was positively correlated with a poor knowledge of wolf habits and inappropriate livestock husbandry practices. Our results suggest a loss of traditional knowledge contributes strongly to the wolf–human conflicts in Georgia. Restoring traditional, simple but good practices—such as protecting herds using shepherd dogs and introducing bulls into the herds—can help one solve this problem.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0580-1) contains supplementary material, which is available to authorized users.  相似文献   

3.
The purpose of this study was to examine the effects of pollution on DNA integrity in the feral soft-shell clam (Mya arenaria) in the Saguenay Fjord. Intertidal clams were collected downstream and upstream of the fjord at sites under anthropogenic pollution. DNA integrity was assessed by following changes in single- and double-stranded breaks, variation in DNA content and micro-nuclei (MN) incidence in hemocytes. The results revealed that clams collected at polluted sites had reduced DNA strand breaks (lower DNA repair activity), increased DNA content variation and MN frequency in hemocytes. The data revealed that DNA content variation was closely related to MN frequency and negatively with DNA strand breaks formation. Water conductivity was also related to reduced MN frequency and DNA content variation, indicating that, in addition to the effects of pollution, the gradual dilution of saltwater could compromise mussel health.  相似文献   

4.
Abstract

Mexacarbate (4‐dimethylamino‐3,5‐xylyl N‐methylcarbamate) insecticide has potential for use in spruce budworm (Choristoneura fumiferana Clem.) control operations in Canada. Its persistence and fate in balsam fir (Abies balsamea (L.) Mill.), litter and soil samples were studied by spraying aerially oil‐based and water‐based formulations, each at 70 g A.I./ha over a coniferous forest near Bathurst, New Brunswick. The oil‐based formulation gave the maximum concentration of the chemical in the substrates studied. In fir needles, the highest concentrations observed were 0.51 ppm and 0.19 ppm (fresh weight) for the oil‐based and emulsion formulations respectively, 1 h after application. The residue levels decreased very rapidly with a half‐life of approximately 5 h. Three and eight days after the spray application of the emulsion and oil formulations respectively, the concentrations of mexacarbate in foliage decreased to trace levels ( 0.008 ppm). Only very low levels of residue were detected in litter and soil. The peak concentrations for the two formulations ranged from 0.02 to 0.11 ppm (fresh weight) in litter and from 0.01 to 0.06 ppm (fresh weight) in soil. The residue levels in both litter and soil decreased to below the detection limit (0.005 ppm) within 1 d. The ground deposit levels found on glass plates and the droplet density and size spectra measured on Kromekote® cards reflected the variations in concentrations found in fir needles, litter and soil samples and correlated with the observed maximum concentrations in them. Under the stipulated use pattern, mexacarbate concentrations found in the terrestrial components studied were low and are not likely to have any undue adverse effects on non‐target species.  相似文献   

5.
Willow and rock ptarmigan were obtained from Northern Québec. Willow ptarmigan were found to have mean cadmium concentrations of 179.7 microg/g (dw) in the kidneys and 25.8 microg/g (dw) in the liver; these levels were three times higher than those found in the rock ptarmigan. The cadmium levels in the ptarmigan were below the threshold above which adverse effects can be observed in birds. The difference between the two ptarmigan species in cadmium content is explained by the diet. A comparison of their diet showed that willow, which stores cadmium, is an important food resource for willow ptarmigan but not for rock ptarmigan. Because there is limited information available on the consumption of ptarmigan kidneys and liver by the Inuit, and the fact that this is a traditional way of life and provides nutritional benefits to the Inuit population, no consumption guidelines are proposed.  相似文献   

6.
The study deals with the identification and the determination of the main monoterpenes (α- and β-pinene) released by the pines in the Landes Forest in France. The measurements were taken after preconcentration using TENAX-GC and thermal desorption. The diurnal variation of atmospheric concentration of α- and β-pinene is established; it is less than 0.5 ppbV in the daytime and varies from 2 to 4 ppbV in the night-time. These variations are explained by the fact that the photochemical reactions and the turbulence phenomena to which the terpenes are exposed change quite radically from day to night. The terpene concentration, higher at 5 m than at 25 m, would seem to confirm the existence of a terpene source at ground level.  相似文献   

7.
8.
9.
Background, aim, and scope  Pharmaceuticals and their metabolites are detected in the aquatic environment and our drinking water supplies. The need for high quality drinking water is one of the most challenging problems of our times, but still only little knowledge exists on the impact of these compounds on ecosystems, animals, and man. Biological waste water treatment in constructed wetlands is an effective and low-cost alternative, especially for the treatment of non-industrial, municipal waste water. In this situation, plants get in contact with pharmaceutical compounds and have to tackle their detoxification. The mechanisms for the detoxification of xenobiotics in plants are closely related to the mammalian system. An activation reaction (phase I) is followed by a conjugation (phase II) with hydrophilic molecules like glutathione or glucose. Phase III reactions can be summarized as storage, degradation, and transport of the xenobiotic conjugate. Until now, there is no information available on the fate of pharmaceuticals in plants. In this study, we want to investigate the fate and metabolism of N-acetyl-4-aminophenol (paracetamol) in plant tissues using the cell culture of Armoracia rusticana L. as a model system. Materials and methods  A hairy root culture of A. rusticana was treated with acetaminophen in a liquid culture. The formation and identification of metabolites over time were analyzed using HPLC-DAD and LC–MSn techniques. Results  With LC–MS technique, we were able to detect paracetamol and identify three of its metabolites in root cells of A. rusticana. Six hours after incubation with 1 mM of acetaminophen, the distribution of acetaminophen and related metabolites in the cells resulted in 18% paracetamol, 64% paracetamol–glucoside, 17% paracetamol glutathione, and 1% of the corresponding cysteine conjugate. Discussion  The formation of two independently formed metabolites in plant root cells again revealed strong similarities between plant and mammalian detoxification systems. The detoxification mechanism of glucuronization in mammals is mirrored by glucosidation of xenobiotics in plants. Furthermore, in both systems, a glutathione conjugate is formed. Due to the existence of P450 enzymes in plants, the formation of the highly reactive NAPQI intermediate is possible. Conclusions  In this study, we introduce the hairy root cell culture of A. rusticana L. as a suitable model system to study the fate of acetaminophen in plant tissues. Our first results point to the direction of plants being able to take up and detoxify the model substrate paracetamol. These first findings underline the great potential of using plants for waste water treatments in constructed wetlands. Recommendations and perspectives  This very first study on the detoxification of a widely used antipyretic agent in plant tissues again shows the flexibility of plant detoxification systems and their potential in waste water treatment facilities. This study covers only the very first steps of acetaminophen detoxification in plants; still, there is no data on long-term exposure as well as the possible impact of pharmaceuticals on the plant health and stress defense. Long-term experiments need to be performed to follow the fate of acetaminophen in root and leaf cells in a whole plant system, and to evaluate possible usage of plants for the remediation of acetaminophen from waste water.  相似文献   

10.

Purpose

Combinatorial bio/chemical approach was applied to investigate dioxin-like contamination of soil and sediment at the petrochemical and organochlorine plant in Pancevo, Serbia, after the destruction of manufacturing facilities that occurred in the spring of 1999 and subsequent remediation actions.

Materials and methods

Soil samples were analyzed for indicator polychlorinated biphenyls (PCBs) by gas chromatography/electron capture detection (GC/ECD). Prioritized soil sample and sediment samples from the waste water channel were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). Microethoxyresorufin o-deethylase (Micro-EROD) and H4IIE?Cluciferase bioassays were used for monitoring of dioxin-like compounds (DLC) and for better characterization of dioxin-like activity of soil samples.

Results

Bioanalytical results indicated high dioxin-like activity in one localized soil sample, while the chemical analysis confirmed the presence of large quantities of DLC: 3.0?×?105 ng/g d.w. of seven-key PCBs, 8.2 ng/g d.w. of PCDD/Fs, and 3.0?×?105 ng/g d.w. of planar and mono-ortho PCBs. In the sediment, contaminant concentrations were in the range 2?C8 ng/g d.w. of PCDD/Fs and 9?C20 ng/g d.w. of PCBs.

Conclusions

This study demonstrates the utility of combined application of bioassays and instrumental analysis, especially for developing and transition country which do not have capacity of the expensive instrumental analysis. The results indicate the high contamination of soil in the area of petrochemical plant, and PCDD/Fs contamination of the sediment from the waste water channel originating from the ethylene dichloride production.  相似文献   

11.
Polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and DDT were examined in the muscle of brown trout (Salmo trutta) from a high mountain lake located in the Pyrenees (Catalonia, Spain) that was used as a model of these lacustrine environments. Results indicate that fish age is the main factor of variability among specimens in this population that is subjected to atmospheric inputs of the organochlorine compounds (OC). Increases of 2- and 20-fold between fish aged 1 year and 15 years old are found. The observed pattern cannot be explained in terms of fish size, condition factor, or muscle lipid content. Higher molecular weight compounds (higher lipophilicity) are better correlated with fish age than low molecular weight compounds. A transformation from 4,4'-DDT to 4,4'-DDE occurs in fish after ingestion; this results in amplified age-dependent signals, especially in male specimens. In contrast, PCB congener #180 has lower age dependence than the general OC group, which could be due to its high hydrophobicity (log K(ow) > 7). In any case, selective accumulation of hydrophobic compounds is already observed among younger fish (age, 1 year). Due to this effect, the relative OC composition does not reflect the main OC pollutants in the lake waters.  相似文献   

12.
Gil C  Boluda R  Ramos J 《Chemosphere》2004,55(7):1027-1034
This study determines total levels of three (Cd, Pb and Ni) potentially toxic trace elements in western Almería (Spain) greenhouse surface soil horizons using microwave digestion; it establishes the geochemical baseline concentration, and it investigates possible relationships between soil properties and elemental concentrations. The results show that the soil concentration of these heavy metals is lower than mentioned in the European and Spanish normative, but they are higher than those reported by other authors working on agricultural soils. The obtained geochemical baseline concentrations (mg kg(-1)) were: Cd 0.4-0.8, Pb 2.5-89.9 and Ni 16.1-30.7. Using the upper baseline criterion, 88% of greenhouse soils have relatively higher content of heavy metals because of their Cd, Pb and Ni concentration. Moreover, soil properties are related to heavy metals contents suggesting that among Cd, Pb and Ni have a similar origin and those total metal concentrations are controlled primarily by soil compositions.  相似文献   

13.
Concentration of heavy metals and natural gross radioactivity were measured in the surface water and sediment of Hazar Lake (Elazi?, Turkey). Eight sampling sites were pre-defined in different locations of the lake. A preliminary study on heavy metals (Zn, Fe, Mn, Ni, Cu, Cr, Co and Pb), major elements (Na, K, Ca, Mg) concentrations and natural radioactivity related to 226Ra, gross-alpha and gross-beta radiations in the surface water and deep sediments were determined. The obtained results showed that, in general, the heavy metals (Zn, Fe, Mn, Ni, Cu and Pb) and major elements (Na, K, Ca, Mg) concentrations in water did not exceed WHO (World Health Organization, 1999), EC (Europe Community, 1998), EPA (Environment Protection Agency, 2002) and TSE-266 (Turkish Standard, 1997) guidelines. Generally, heavy metals and major elements concentration of the sediments were found decrease in sequence of Fe>Mg>Ca>Mn>Zn>Ni>Cr>Cu>Co>Pb. The results of this study indicated that a general absence of serious pollution in the Hazar Lake. The results obtained from the radioactivity determination indicate that the surface water radioactivity concentration of 226Ra, gross-alpha and gross-beta were ranging from 0.52+/-0.02 to 2.02+/-0.06 Bq/l and from 0.65+/-0.03 to 2.52+/-0.07 Bq/l and from 0.01+/-0.01 to 0.14+/-0.01 Bq/l, respectively. Deep sediment radioactivity concentrations of 226Ra is ranging from 0.07+/-0.03 to 0.32+/-0.07 Bq/g.  相似文献   

14.
Atmospheric ammonia mixing ratios and the main inorganic ions NH4+, NO3 and SO42− of size-resolved particles in the range from 0.05 to 10 μm were measured at an urban site in Münster, Germany. High mixing ratios of ammonia with a median of 5.2 ppb and a maximum of 50 ppb were detected. The mass fraction of submicron particles was much higher during the day than at night. At night, a greater particle mass and an increased presence of particulate nitrate was measured. Recurring patterns of particle distribution were distinguished and their characteristics analysed. In half of the measurements, the accumulation mode was clearly dominating, which is an indication of aged aerosol. In some measurements, higher concentrations of fine particles were found indicating particle formation. In these cases, a smaller particle mass and about four times greater ratios of ammonia versus ammonium concentrations were observed. These data show that ammonia contributes considerably to the formation of secondary particulate material.  相似文献   

15.
The first attempt to systematically investigate the atmospheric mercury (Hg) in the MBL of the Augusta basin (SE Sicily, Italy) has been undertaken. In the past the basin was the receptor for Hg from an intense industrial activity which contaminated the bottom sediments of the Bay, making this area a potential source of pollution for the surrounding Mediterranean. Three oceanographic cruises have been thus performed in the basin during the winter and summer 2011/2012, where we estimated averaged Hgatm concentrations of about 1.5 ± 0.4 (range 0.9–3.1) and 2.1 ± 0.98 (range 1.1–3.1) ng m−3 for the two seasons, respectively. These data are somewhat higher than the background Hgatm value measured over the land (range 1.1 ± 0.3 ng m−3) at downtown Augusta, while are similar to those detected in other polluted regions elsewhere. Hg evasion fluxes estimated at the sea/air interface over the Bay range from 3.6 ± 0.3 (unpolluted site) to 72 ± 0.1 (polluted site of the basin) ng m−2 h−1. By extending these measurements to the entire area of the Augusta basin (∼23.5 km2), we calculated a total sea–air Hg evasion flux of about 9.7 ± 0.1 g d−1 (∼0.004 t yr−1), accounting for ∼0.0002% of the global Hg oceanic evasion (2000 t yr−1). The new proposed data set offers a unique and original study on the potential outflow of Hg from the sea–air interface at the basin, and it represents an important step for a better comprehension of the processes occurring in the marine biogeochemical cycle of this element.  相似文献   

16.
Sicyos polyacanthus is one of the most important weed in sugarcane crops of Tucumán (Argentina). The objective of this work was to establish strategies that would decrease the weed incidence in the crop to a minimum level. The study was carried out during 1998--2003 at five localities of sugarcane production of Tucumán (Argentina). The plots were 20 m long (192 m2) with 6 furrows and each plot was replicated five times. Treatments were: (i) Mechanical-chemical cultivation without fire; (ii) Mechanical-chemical culltivation with fire; (iii) Mechanical cultivation with handle pulled and with fire; (iv) Mechanical cultivation with handle pulled without fire; (v) Mechanical and chemical variants with fertilization and without fertilization; (vi) Mechanical and chemical variants with watering and without watering; (vii) Fallow and rotation, at the sugarcane crop renovation; (viii) Mechanical and chemical variants for plant cane and ratoon cane; and (ix) Mulching of harvest rests. The results suggest that besides the use of preemergent herbicides, fire marks the entry point of control, influencing fluxes and seed viability. It appears that fallow, mulching, and rotation of crops is fundamental for eliminating seeds that live short time in the soil and increase the mortality rate of species.  相似文献   

17.
Polkowska Z 《Chemosphere》2004,57(10):1265-1274
Chlorinated and brominated derivatives of methane and ethene were determined in samples of atmospheric precipitation collected between November 2000 and May 2001 at four sites in two cities, Gdańsk and Sopot, located on the Gulf of Gdańsk (Baltic Sea, Poland). The analytes were determined by direct aqueous injection of the samples to the capillary column using ECD detection (DAI-GC-ECD). Chloroform and carbon tetrachloride were detected the most often at all sites. The highest concentrations of the analytes were recorded at the intersection of two major streets (no. 3), next to a major route leading to two subdivisions (no. 2) and at Narutowicza Street (no. 1). In general, analyte concentration levels were lower during the spring months. During precipitation, concentrations of the analytes were higher in samples collected at the beginning of the event due to scavenging of the volatile compounds from the atmosphere. After a period of 75 min from the beginning of the precipitation event, analyte concentrations were lower by 10-80%, depending on the initial concentration and nature of the analyte.  相似文献   

18.
The purpose of the present study was to research the sublethal and/or lethal effects produced by the exposure of fish and shellfish to the γ isomer of lindane, γ-hexachlorocyclohexane (γ-HCH). The teleostean fish Sparus aurata and the shellfish Crassostrea angulata and Scrobicularia plana, were exposed to 16 μ g/L of lindane for 15 days. Samples of different fish (liver, kidney and gills) and shellfish (gills, gut, digestive gland and mantle) tissues were extracted and processed for histopathological observations. Although mortality was not detected during the bioassay, sublethal effects (histopathological alterations) were observed. Vacuolization in the liver cells and lamellar fusion in gills from exposed fish were observed. Disorganization of normal gill structure, epithelial desquamation with the disappearance of apical ciliature in intestine, and inflammatory response in mantle from exposed shellfish were also observed. Thus, it can be concluded that the lindane concentration employed in the present research did not produce lethal effects in the exposed organisms but it caused sublethal effects. Lindane has time-dependent multiple toxic effects in S. aurata, C. angulata and S. plana, which were more severe at the end of the experimental time. The toxicological implications arising from these results are subjects for further multiconcentration tests dealing with lethal responses (mortality) or with sublethal responses (cellular/molecular biomarkers) of the aforementioned species.  相似文献   

19.
Polycyclic aromatic hydrocarbons (PAHs) are widespread fused-ring contaminants formed during incomplete combustion of almost all kind of organic materials from both natural and anthropogenic sources. Some PAHs have been shown to be carcinogenic to humans, and a wide range of PAHs are found in wildlife all around the globe including avian species. The purpose of this project was to assess the effects of a standard mixture of 16 PAHs (United States Environmental Protection Agency) on the hepatic fatty acid β-oxidation in chicken embryos (Gallus gallus domesticus) exposed in ovo. The hepatic β-oxidation was measured using a tritium release assay with [9,10-3H]-palmitic acid (16:0) as substrate. Treated groups were divided into groups of 0.05, 0.1, 0.3, 0.5, and 0.8 mg PAHs/kg egg weight. The hepatic β-oxidation was reduced after exposure in ovo to the 16 PAHs mixture compared to control. The mechanisms causing reduced fatty acid oxidation in the present study are unclear, however may be due to deficient membrane structure, the functionality of enzymes controlling the rate of fatty acid entering into the mitochondria, or complex pathways connected to endocrine disruption. To the best of our knowledge, this is the first time a PAH-caused reduction of hepatic β-oxidation of fatty acids in avian embryos has been observed. The implication of this finding on risk assessment of PAH exposure in avian wildlife remains to be determined.  相似文献   

20.
The Altata-Ensenada del Pabellón lagoon system is located in the central part of Sinaloa state, NW Mexico. The major sources of pollution are represented by the waste effluents from the intensive agriculture and the urban sewage from the cities of Culiacán (population of 750 000) and Navolato (population of 50 000). In this lagoon system diverse penaeid shrimps occur; the crystal shrimp Farfantepenaeus brevirostris, the brown shrimp F. californiensis, the blue shrimp Litopenaeus stylirostris, the white shrimp L. vannamei and the Pacific seabob Xiphopenaeus kroyeri. With the purpose of knowing distribution and relative concentrations of Hg in the main tissues of penaeid shrimps, levels of Hg in five species from Altata-Enesenada del Pabellón lagoon on the SE Gulf of California were determined. Analysis were carried out by reducing mercury compounds after acid digestion reduction with SnCl2 and detection by cold vapour atomic absorption. In general, hepatopancreas was the tissue where Hg was mostly accumulated, followed by muscle and exoskeleton. The sequence of Hg concentrations in the five species studied here for every tissue was: hepatopancreas L. vannamei > F. californiensis > L. stylirostris > F. brevirostris > X. kroyeri; muscle L. stylirostris > F. brevirostris > L. vannamei > F. CALIFORNIENSIS=X. kroyeri and exoskeleton F. brevirostris > F. californiensis > L. vannamei > L. stylirostris > X. kroyeri.  相似文献   

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