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Abstract

Some cultural heritage sites in Jordan are in urban areas being exposed to anthropogenic pollution. Therefore, it is important to evaluate the contamination at these sites to protect them. Here, we considered a Roman archeological site (Nymphaeum) situated in Amman. The contamination in soil, plants, and building stones did not show spatial distribution within the site. The contamination was the highest in soil (heavy metals 104–107 ppb and sulfur ~3.5´106 ppb) whereas in plants was the least for Cr (~400 ppb) and in building stones it was the least for Cu (~860 ppb). The highest contamination in plants and building stones was found for Al (~5´104 and ~6.2´105 ppb respectively). The sulfur content in plants (~7.6´105 ppb) was higher than that in the building stones (~2.3´105 ppb). The heavy metals and sulfur contamination in the building stones were lower than what was reported elsewhere outside Jordan.

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The aim of our study was to assess the strategy developed by terrestrial plants growing in an area contaminated by arsenic to avoid or minimize the toxic effects caused by this element. Eight plant species from two arsenic-contaminated areas were selected for the investigation. Arsenic uptake by different plants was discussed. The speciation analysis of arsenic in plant leaves was performed as well and both inorganic As(III) and As(V) were detected. Moreover, the concentration of phytochelatins in the investigated terrestrial plants was determined. It was noted that the highest concentration of arsenic was found in herb Robert (Gernium rober-tianum) 21 mg·kg-1 and common nettle (Urtica dioica) 5.3 mg·kg-1 in the cases of Złoty Stok and Łomianki, respectively. Phytochelatins were present in all investigated plant species: PC3 was present in the highest concentration in plants from Złoty Stok (compared to other phytochelatins) while none of the phytochelatins dominated in plants from Łomianki. A correlation between concentrations of phytochelatin and arsenic was found in one of the nettle samples from Łomianki.
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Heavy metals are bioaccumulated and biotransferred both by natural and anthropogenic sources. The contamination by heavy metals in plants and water is one of the major issues to be faced throughout the world and requires attention because heavy metals above their normal ranges are extremely threatened to both plant and animal life. It was therefore of interest to conduct study to estimate levels of heavy metals in plants, water and soil of Tanda dam kohat. Soil and water samples were also analyzed for physico-chemical parameters such as pH, hardness and electrical conductivity. Water samples were collected at random from the water reservoir of Tanda dam kohat. About 13 samples of water and 13 soil samples were collected at random and four wild plants namely Xanthium strumarium, Acacia modesta, Dodmea viscosa and Tamarix aphyda were collected from the same region. Heavy metals for which these samples were analyzed were cadmium, zinc, iron, copper, nickel, chromium and lead. Plants samples were analyzed separately for their root, stem and leaves. Flame absorption spectrometer was used for analyzing the samples. Results showed that concentrations of cadmium, chromium, iron and lead in water were recorded above the permissible limits set by WHO while zinc and copper were recorded below the permissible limits and no concentration of nickel was recorded in water samples. pH of all water samples was recorded below the normal range while hardness and electrical conductivity of all water samples were recorded above the normal range set by WHO. Concentrations of heavy metals in soil were also compared with WHO standards for heavy metals and in soil samples concentration of heavy metals were recorded above the permissible limits except zinc which was recorded below the permissible limits set by WHO. pH of all soil samples was recorded below the normal range while electrical conductivity of all soil samples was recorded above the normal range.
Article
Heavy metal accumulation in crops and soils from wastewater irrigation poses a significant threat to the human health. A study was carried out to investigate the removal potential of heavy metals (HM) by native plant species, namely Cannabis sativa L., Chenopodium album L., Datura stramonium L., Sonchus asper L., Amaranthus viridus L., Oenothera rosea (LHer), Xanthium stramonium L., Polygonum macalosa L., Nasturtium officinale L. and Conyza canadensis L. growing at the municipal wastewater site in Abbottabad city, Pakistan. The HM concentrations varied among plants depending on the species. Metal concentrations across species varied in the order iron (Fe) > zinc (Zn) > chromium (Cr) > nickel (Ni) > cadmium (Cd). Majority of the species accumulated more HM in roots than shoots. Among species, the concentrations (both in roots and shoots) were in the order C. sativa > C. album > X. stramonium > C. canadensis > A. viridus > N. officinale > P. macalosa > D. stramonium > S. asper > O. rosea. No species was identified as a hyperaccumulator. All species exhibited a translocation factor (TF) less than 1. Species like C. sativa, C. album and X. stramonium gave higher (> 1) biological concentration factor (BCF) and biological accumulation coefficient (BAC) especially for Fe, Cr and Cd than other species. Higher accumulation of heavy metals in these plant species signifies the general application of these species for phytostabilization and phytoextraction of HM from polluted soils.
Article
The behaviour of several porous carbonate building stones used in Spanish and English monuments was compared. Stones were exposed to urban and suburban environments and subjected to simulated SO atmospheres in the laboratory. Physical 2 properties that affect the transfer of moisture were determined before and after exposure, and related to the degree of reaction of the stones. The degree of reaction was determined by analysing the reaction products. Results showed that physical properties influenced the reactivity of the stones. These characteristics also changed as the stones weathered due to the different concentrations of impurities in the material. Moreover, stones with a high specific surface area andror a deliquescent salt content may promote more NO dry deposition. ᮊ
Article
The aim of the study is the evaluation of different heavy metal pollution indicators to efficiently track atmospheric contamination. The investigation considered both soils and vegetation samples (grass, leaves and pine needles, wood branches, bark). Sampling sites were selected in Northern Italy (Piedmont region), in areas with a known contamination history. Heavy metals were determined on acid digested sampled by ICP-OES. In addition, wood cores were also taken from selected conifer species in order to test the applicability of LA-ICP-MS to the analysis of heavy metals in tree rings. Soils can be considered good indicators of environmental quality. Grass samples reflect heavy metal abundances in the top soil while pine needles seem to well reflect the local atmospheric contamination levels. Finally, despite analytical problems, LA-ICP-MS can be considered a suitable technique for quantitative analysis of wood samples, with potential application to dendroanalytical investigations.
Article
This work presents results from a petrographic, morphological and chemical study of the black crusts developing on monuments in three Italian cities, the Cathedral of Milan, the Cathedral of St. Maria del Fiore in Florence, and the Vittoriano Monument in Rome. Black crusts (BCs) were studied with traditional techniques such as optical microscopy (OM), scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM-EDS) and infrared spectroscopic techniques (FT-IR), in combination with laser ablation inductively coupled mass spectrometry (LA-ICP-MS), which has shown itself to be particularly useful in determining concentrations of heavy metals in BCs. Although the BCs of the three monuments show general enrichment in heavy metals with respect to the substrate (S), interesting differences were observed among them. In particular, BCs from Milan are the richest in heavy metals, particularly Pb and Zn, reflecting the severe air pollution of this very large city, which, in addition to its intense traffic, is located in the most highly industrialized area of Northern Italy. The BCs from the south-eastern side of the Cathedral of St. Maria del Fiore in Florence, facing a pedestrian area, show little enrichment in heavy metals, and those from the Vittoriano Monument in Rome, which is exposed to intense road traffic, display variable enrichment, attributable to mobile emission sources. Results show that the various enrichment trends in heavy metals observed in the BCs of these three monuments are due to many factors: various sources of anthropogenic pollution, sampling height, exposure, orientation, and the shape of the deposition surface.
Article
The protection of stone monuments against deterioration has recently attracted much attention from scientists. An accurate analysis of the degradation mechanisms of stones has led to the conclusion about the necessity of protection especially against the condensed water and the salts formation. In this study, the strengthening effect of nanoparticles-based treatments is compared to that exhibited by a silane commercial polymer. The surface properties of these types of smart coatings were investigated by different analytical techniques such as contact angle measurements and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS). Aimed at evaluating the coating performance, exposure tests both to UV ageing and to environmental atmospheric pollution were carried out. Diffuse reflectance spectroscopy (DRS) was employed for the CIELab colorimetric coordinates assessment; while ion chromatography (IC) was adopted to evaluate the coating capacity to avoid salts (Cl−, NO3− and SO42−) formation.
Article
Concentrations of Fe, Mn, Zn, Pb, Cu and Cd in soil solutions taken in the vicinity of a sulphur mine range from 354 to 9080 μM L−1, and exceeded the concentrations measured in solutions from light acid arable soils. The content of each metal was a negative function of either the solution pH or of Ca concentration. Reclamation of S-contaminated soil by an application of 2000 tonnes of limestone per hectare did not significantly affect the solubility of trace metals, whereas equilibration of soil samples with CaCO3 in the laboratory decreased solubility of metals, especially in the soil under moist conditions. Sulphur deposition may modify the natural cycling of metals in soils.
Article
This paper studies the black soiling rate of building granite, marble and limestones in two urban environments with different climates.Specimens were placed horizontally, sheltered and unsheltered from rainfall. Colour changes were monitored. Changes in L∗ were utilised to determine the total darkening of the stones and their soiling rate and were compared by statistical analysis.Black soiling depended on the type of stone and exposure. Limestones, mainly, showed a soiling proportional to the square root of the time of exposure. In this case, soiling coefficients could indicate frequency of necessary cleaning. The rest of the selected stones did not show such an evident relationship.The soiling tendency of all sheltered limestones was quite similar and more severe than in marble and granite. Soiling was related to the stone colour, type of voids and surface characteristics. Soiling of unsheltered specimens also seemed to depend on the rainfall conditions (rain periods, intensity, amount, temperature, etc.), which could influence both particle deposition and removal from stone surfaces.
Article
Plants are sensitive to sulfur dioxide and they are affected by it both directly and indirectly. The direct effects may be acute or chronic, depending on the duration and intensity of the exposure. Sulfur dioxide inhibits photosynthesis by disrupting the photosynthetic mechanism. The opening of the stomata is promoted by sulfur dioxide, resulting in an excessive loss of water. The cumulative effect of sulferous pollution is to reduce the quantity and quality of plant yield. Generally, its impact is more severe when in combination with other pollutants such as oxides of nitrogen, fluorides, and ozone. At the ecosystem level, sulfur dioxide affects species composition by eliminating more sensitive species. This reduces primary productivity and alters trophic relationships which have far‐reaching implications for the animal and microbial populations in the community. Another indirect effect results from the acid rain which leaches out nutrients from plant canopy and soil. The acidic run‐off changes the pH of the receiving waters and adds large quantities of nutrients which disturb the equilibrium of aquatic communities. Plants vary widely in their tolerance to sulfer dioxide. Lichens and bryophytes are among the most sensitive and have been successfully used as indicators of sulfur dioxide pollution.
Article
Conservation of historical buildings is an important issue. The environmental conditions seriously affect the monumental stones. Although different coating materials were tested, the polymeric materials have been showing the most promising results for protection of archeological stones. Therefore, in the current study, the acrylic polymer was used for conservation of monuments made of sandstone and limestone. The adsorption of the acrylic polymer onto both stones was analyzed and the durability of the coatings under different environmental conditions was tested and simulated by artificial aging. Moreover, the mechanism of polymer–stone interactions was elucidated by interfacial characterization techniques.The results showed that the adsorption of polymer onto either stones is physical as shown by Fourier transform infra-red (FTIR) and electrokinetic measurements. In addition, the presence of polymer coating shows a significant improvement in physical and mechanical properties of the treated stones, e.g., increase in bulk density from 1.9 to 2.3 g/cm3 and decrease in porosity from 15.8% to 2.7% as well as the noticeable increase in compressive strength. All these measures indicated the suitability of acrylic polymer for conservation of either stones.
Article
The protective performances of two new fluorinated acrylic copolymers (based on the monomers 1H,1H,2H,2H-perfluorodecyl mathacrylate (XFDM) and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate (HFIM) are evaluated and compared with Paraloid B72, a commercial copolymer ethyl methacrylate/methyl acrylate (EM/MA) and its partially fluorinated homologus 2,2,2-trifluoroethyl methacrylate/MA (TFEM/MA). The polymeric materials have been tested on Candoglia marble, a very low open porosity stone (<1%) used in Italian historical architecture (Milan Cathedral). The copolymer were tested according to UNI-Normal protocol. Measurements of capillary water absorption, static contact angles, colour variation and water vapour permeability were made before and after accelerated photo-ageing. FTIR spectroscopy and size exclusion chromatography (SEC) analyses were carried out on samples aged on inert substrate to assess the photostability of the copolymers themselves. The relationship between the protection efficacy and the fluorine content and distribution has been investigated. The results obtained show that the addition of a partially fluorinated co-monomer to the Paraloid B72 copolymer structure did not result in the expected improvement of the coating properties, while the fluorination of the copolymer side chain gave rise to encouraging performance.
Article
The effects of carbonaceous particles and heavy metals in the interaction between sulfur dioxide and mortars were investigated in a laboratory exposure system. Simulation experiments were carried out in a flow chamber where temperature, relative humidity and SO2 concentration were controlled. Samples of lime, pozzolan and cement mortars were exposed for 150 days in air with 3 ppm of SO2 concentration at 25°C and 95% RH. The mortar specimens were coated with three types of carbonaceous particles, collected at the emission points of three oil-fueled combustion sources, and, for comparison, with particles of active carbon, pure graphite, iron oxide and vanadium oxide. After exposure, the mortar samples were analyzed by x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) to identify the main chemical species, by ion chromatography (IC) to quantify SO 4−− and SO 3−− concentration and also by scanning electron microscope (SEM). The results show that the amount of SO 4−− forming increases in the presence of carbonaceous particles and is related to their heavy metal content.
Article
Marble and limestone briquettes were placed at National Acid Precipitation Assessment Program (NAPAP) test sites in North Carolina, Washington, D.C., New Jersey, and New York to determine mineralogical changes that might be attributed to acid deposition. Samples have been examined after exposures of 1 and 2 yr, and the most significant change is the development of a gypsum-rich spot on the sheltered side of the briquettes. X-ray and SEM analyses reveal that gypsum plus calcite is present within the spot area, but outside this area and on the upper surface of the briquettes, only calcite is detected. Rounded particles, morphologically similar to various C soots, were also observed, and it is suggested that these may catalyze the oxidation of SOâ to HâSOâ. The atmospheric chemistry relating to acid deposition is presented and interpreted in terms of the gas concentrations and rain chemistry measured at the four sites. Statistical analysis of possible relationships between various ion concentrations from the sites reveals some significant correlations. Strong correlations are found between SO²⁻â and H{sup +}, between NO⁻â and H{sup +}, and between H{sup +} and SO²⁻â + NO⁻â. There are also high correlations between SO²⁻â and NO⁻â at three sites. A model, based on the sequence of salts observed to crystallize from a progressively more concentrated solution, is presented to explain the presence of the spot on the undersides of the briquettes. Two possible crystallization sequences are outlined: first for the system CaCOâ-CaSOâ-HâO and second for the system CaCOâ-CaSOâ-Ca(NOâ)â-HâO. It is proposed that the most significant stone damage is due to salt build up on and within the stone rather than due to stone removal through dissolution.
Article
Damage caused to objects of cultural heritage is one of the most serious detrimental effects of air pollutants. Within the 6th Framework Programme of the EU, the CULT-STRAT project is an inter-agency, multi-disciplinary project that has integrated research and monitoring information to provide answers to policy and management questions, which relate the effects of air pollutants on heritage and the management options available to mitigate them. The overall aim of the project has been to assess and predict the effects of different pollutants on materials and objects of cultural heritage in a multipollutant scenario and to identify indicators and thresholds levels of pollutants. These have been used for development of management strategies for sustainable maintenance and preventive conservation of European Cultural Heritage and air quality policy from continental to local scale.The present paper reports one of the studies carried out in the CULT-STRAT project at city level and focused on the town of Madrid (Spain). Different maps are shown for the present and possible future scenarios (2010 and 2020): inventory of stock of cultural heritage for each selected material, concentration of selected pollutants (SO2, NO2, O3 and PM10), corrosion (cast bronze) and recession (Portland limestone), exceedance of tolerable degradation thresholds for each material and corrosion-cultural heritage overlapped maps.Research highlights► A methodology for the evaluation of Cultural Heritage at risk has been developed. ► A case-study focused on the city of Madrid, as example, is presented. ► Two materials have been considered: cast bronze and Portland limestone. ► Mainly, the effect of pollution reduction has been studied. ► Mapping: pollutants, corrosivity, exceedance and future scenarios.
Article
Austria has been participating in the “European Moss Survey” within the UN-ECE ICP-vegetation since 1991. Three consecutive sampling periods in 1995, 2000 and 2005 were performed. Five moss species at 220 sampling sites (2.5 sites 1000 km−2) were analysed for Al, As, Cd, Co, Cr, Cu, Fe, Hg, Ni, Mo, Pb, V, and Zn concentrations. According to the retrospective analysis by 3-year-old moss segments, this investigation covered deposition in the period between 1989 and 2005. A relocation of sampling sites (within 2 km2) was necessary for <10% of the sites within the overall period. On an Austria-wide scale all metals with the exception of Co, Cd and Hg showed a significant decrease of concentrations in the observed period. On a regional or site scale a large deviation from this general trend could be found, leading to significant differences between regions for many elements (e.g. for Co, Pb and Zn). Even continuous increases of metal deposition could be found at several sites (e.g. for Mo and Cu). This implies that pollution levels at different scales should be looked at in a differentiated way even in times of generally decreasing metal deposition.
Article
Tolerance to lead of three of Allium cepa L. varieties grown from seeds and bulbs was compared. In all cases plants developing from bulbs were found more tolerant to lead than those developing from seeds. During 10 days of exposure to lead, the difference in the tolerance index between adventitious and seedling roots was 24% on average (7-61% depending on the plant variety and the dose of lead), which was significant. In all cases, the seedlings contained more lead in their tissues than the plants that had developed from bulbs. This observation may explain a difference in lead tolerance between these developmental phases of Allium cepa.
Article
Medicinal, aromatic and spice plants grown in different regions of Austria were monitored as to their Cd, Cu, Fe, Mn, Pb and Zn contents. Since the plants were grown under common field conditions, the essential elements were within the usual ranges for plant material. The contamination level with the toxic heavy metals, Pb and Cd, can be classified as normally low. Most samples contained less than 0.2 mg kgу Cd and less than 1.5 mg kgу Pb on a dry weight basis. Comparison with previous investigations suggests that contaminations with Pb occur rather by chance, whereas enhanced Cd values are restricted to some species having a tendency to accumulate this heavy metal. Some such species are St. Johns wort, poppy, yarrow, chamomile and absinth. Careful choice of growing site and appropriate soil management can reduce the Cd uptake of these critical species. These precautions are important when larger amounts of the product are consumed.
Article
Here we present results of a survey conducted to identify and characterize spontaneously growing arsenic-tolerant plant species of the area around the old arsenic/gold mine in ZlotyStok (Poland), with respect of their potential use in phytoremediation. Plants and soil from their rhizosphere were sampled and analyzed for concentrations of As and accompanying Mn, Fe, Mg, Ca, Al, Cu, Zn, Ba, Pb, Ni, Cs, V, Cr, Sr, Rb, Bi, Mo and U. The soil contained primarily very high As, Pb and Al concentrations (up to 7,451, 1,058 and 31,272mg/kg respectively). The ability of identified species to modify the amount of bioavailable arsenic in their rhizosphere was determined by single extractions of soil samples with the use of water, phosphate buffer, EDTA, and acetic acid. Although As-hyperaccumulators were not found, Calamagrostis arundinaca was identified as a new species which successfully carried out the natural phytoextraction of arsenic. This plant was able to increase substantially the arsenic availability in the soil, and likely due to efficient uptake decreased the total As concentration within the root zone by around 40% relative to the reference soil. Thus, it has high potential for phytoremediation. The lowest amount of available arsenic was found in the rhizosphere of Stachys sylvatica, the species with the lowest As shoot concentration (compared with other plant species). It was proposed as a good candidate for phytostabilization.
Article
Phytoremediation is a promising alternative to conventional soil clean-up methods; however, up to date, there is still not enough information on plant species suitable for application in this field of science. Therefore, plant screening on contaminated sites can lead to the identification of further species of interest. In the present study, pedological and botanical characteristics of an industrialised area known for its metal contamination, in special with Zn—Esteiro de Estarreja, in Portugal—were examined in a 1-year screening. Twenty-seven species were found, with a higher occurrence and variability in the summer/spring season. Zinc levels in the tissues of the collected plant samples ranged from 34mgkg−1 in shoots to 2,440mgkg−1 in roots of different species. Species as Verbascum virgatum, Hypochoeris radicata, Phalaris arundinacea, Conyza bilbaoana, Paspalum urvillei and Aster squamatus have shown high Zn shoot accumulation and bioconcentration factors (BCFshoots > 1) and high metal translocation factors (TF > 1). Others, namely Spergularia capillacea, excluded Zn from the shoot tissues and stored the metal at the root zone (BCFroots > 1), behaving as tolerant plants. Plants were also screened for arbuscular mycorrhizal fungi colonisation, and only few species showed mycorrhizal presence, namely C. bilbaoana, Hirschfeldia incana, Epilobium tetragonum, Conyza sumatrensis, Pteridium aquilinum, P. urvillei and A. squamatus. The present work showed important indigenous species that can cope with installed harsh conditions and with potential for utilisation in phytoremediation strategies, either through metal removal to aerial parts or through its immobilisation in the root zone. KeywordsSoil–Phytoremediation–Arbuscular mycorrhizal fungi–Zn–Bioavailability–Survey
Article
This study was set out to assess the characteristics and significance of metal contents emitted from diesel engines. We found that the emitted concentrations of crust elements (including Al, Ca, Fe, Mg, and Si) were much higher than those of anthropogenic elements (including Ag, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Sr, Ti, V, and Zn) from diesel vehicle engine exhausts under the transient-cycle condition. The emission concentrations of particulate matters from diesel vehicle engine were inversely proportional to the specified engine speeds. To the contrary, the increase of engine speeds resulted in increase of fractions of metal contents in particulate matters. We conducted simple linear regression analysis to relate the emission rates of the metal contents in vehicle exhaust to the consumption rates of metal contents in diesel fuel. This study yielded R2=0.999 which suggests that the emission of the metal contents in vehicle exhaust could be fully explained by the consumption of metal contents in diesel fuel. For illustration, we found that the annual emission rates of both crust and anthropogenic elements from all diesel engine vehicles (=269 000 and 58 700 kg yr−1, respectively) were significantly higher than those from the coal power plant, electrical arc furnace, and coke oven (=90 100 and 1660 kg yr−1, 2060 and 173 kg yr−1, and 60 500 and 3740 kg yr−1, respectively) in Taiwan area. The relatively high amount of metal contents emitted from diesel engines strongly suggests that the measurement on the control of metal contents in diesel fuel should be taken in the future.