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Timor island is located north of Australian Continent and is one of the southeasternmost Sunda islands. In a tectonic context, is located at the collisional margin between the oceanic Banda volcanic arc and the Australian continental margin. The island does not have a volcanic nature and is made up of three main tectonostratigraphic sequences : i) Australia Affinity Sequence, that comprises units whose ages range from the Upper Carboniferous to the Late Miocene, deposited on Australian continental or transitional continental crust prior to collision with the Banda Terrane; ii) Banda Arc Terrane Sequence, that comprises the allochthonous forearc units of the Banda volcanic arc and are of Asia affinity. They span from Jurassic to Pliocene in age; iii) Banda Orogen Sequence, consisting of units that have formed or been deposited since the start of collision of the continental margin with the Banda forearc, ages spanning from upper Miocene to present.The Manamas Mountain is an elevated region located in the northeast sector of the Timor-Leste Oecusse enclave, largely built up of volcanic rocks of Late Miocene age (Manamas Formation; Banda Arc Terrane Sequence). It may represent a fragment of the Banda Arc overthrusting on the northernmost edge of the Australian continental margin.Recognition of the main structural lineament systems of the Manamas Mountain and definition of its main morphostructural characteristics to complement structural and geological mapping are the main goals of the present study, which aims to determine such aspects through interpretation of spatial remote detection digital data acquired by the Landsat satellite's sensor (ETMþ) and the Earth satellite's sensor (Aster) and aerial orthophoto maps.

This study investigates the impact of Glomus mosseae on heavy metal(loid) (HM) uptake efficiency of pea (Pisum sativum L.) plants along with physiological and biochemical parameters. Plants were gr...

This study investigates the impact of

In the present study, the phytoremedation potential along with growth, physiological and biochemical response of tomato (Solanum lycopersicum) was assessed under heavy metal(loid) (HM) and arbuscular mycorrhizal fungus (AMF) amendment. Effect of AMF on uptake and accumulation of metal(loid)s was assessed and accumulation characteristics were expressed in terms of bioabsorption coefficient (BAC), bioconcentration factor (BCF), translocation factor (TLF) and transfer factor (TF). Results showed that AMF-inoculated plants showed not only a better growth, chlorophyll content, strengthened non-enzymatic and enzymatic defense mechanism, but also accumulated higher concentration of metal(loid)s. The correlation between biochemical and physiological parameters was significant at 0.01 level. A significant difference (p ≤ 0.001) in antioxidant enzyme activity was found on increasing metal(loid) dose and application of AMF. The accumulation of Cd and Pb in edible part exceeded the chronic reference dose stated by USEPA. The target hazard quotient (THQ) was >1 for Cd and Pb, whereas

Aquatic bryophytes can accumulate extremely high levels of chemical elements because of their unique morphology and physiology which is markedly different from vascular plants. Four aquatic mosses—Fontinalis squamosa, Brachythecium rivulare, Platyhypnidium riparioides, Thamnobryum alopecurum—and a freshwater red alga Lemanea fluviatilis along with water samples from the streams of Gois mine region in Central Portugal were analyzed for 46 elements. Despite being below detection levels in the water samples, the elements Zr, V, Cr, Mo, Ru, Os, Rh, Ir, Pt, Ag, Ge and Bi were obtained in the plant samples. The moss T. alopecurum had the highest mean concentrations of 19 elements followed by B. rivulare (15 elements). Maximum accumulation of Rb, Ta and Au, however, was seen in the alga L. fluviatilis. Bioconcentration factors > 106 were obtained for a few metals. The investigation confirms that aquatic bryophytes can be suitable for water quality biomonitoring and biogeochemical prospecting in fresh water bodies owing to their high accumulative capacity of multi-elements from their aquatic ambient.

Arbuscular mycorrhizal fungi (AMF) aids in plant establishment at heavy metal(loid) (HM) contaminated soils, strengthening plant defense system along with promoting growth. A pot experiment was carried out to evaluate the effect of AMF on eggplants grown under HM stress. Further, the potential health risks of HM exposure to the humans via dietary intake of eggplant were also estimated. Results showed that AMF application improved growth, biomass and antioxidative defense response of plants against HM stress. Significant difference (p ≤ 0.001) in parameters under study was found on increasing metal dose and on application of AMF. Among metal(loid)s maximum uptake was recorded for Pb (29.64mgkg-1 in roots; 23.08mgkg-1 in shoot) followed by As (3.84mgkg-1 in roots; 8.20mgkg-1 in shoot) and, Cd (0.96mgkg-1 in roots; 2.12mgkg-1 in shoot). Based on the accumulation of HM in edible part, Hazard Quotient (HQ) was calculated. HQ was found to be > 1 for Pb, which highlights the risks associated with consumption of Eggplants grown on Pb contaminated soil. However this potential, which was further enhanced by application of AMF, can be harnessed for on-site remediation of Pb contaminated soils. The content of Cd and As in the edible part was found to be within safe limits (HQ < 1) when compared to chronic reference dose stated by USEPA.

Mitochondrial DNA (mtDNA) mutations have been assigned as a major cause of genetic disease. When a novel sequence variation is found, it is necessary to evaluate its functional impact, usually requiring functional molecular studies. Given the fact that this approach is difficult to put in practice in a routine basis, it is possible to take advantage of the in silico tools available and predict protein/RNA structure changes and therefore pathogenicity. Here, we describe the characterization of five undescribed mtDNA variants, upon detection of 23 unclassified alterations at Laboratory of Biochemical Genetics, from 2004 to 2014. Those five sequence variations are located in protein-coding genes, in five patients with a diverse range of mitochondrial respiratory chain disease phenotypes including encephalopathy, optic neuropathy, developmental delay, deafness and epilepsy. According to the prediction established by in silico analysis using tools to predict structure and function changes (ClustalW2®, PolyPhen-2®, SIFT®, MutationAssessor®, PredictProtein®, Provean®, I-TASSER®, Haplogrep®), from the 23 variants analyzed, the five described are potentially pathogenic. This approach is inexpensive and compatible with a rapid first line response to clinical demanding, contributing to a more rationale genetic diagnosis concerning novel mutations and to clarify the mtDNA involvement in these pathologies.

Timor-Leste and Oecusse in particular have very little geological data coverage due to the many conflicts generated mainly by Portuguese colonization and Indonesian occupation. The main work that has been done was aimed at oil prospecting on the south coast. A regional stream sediment campaign was started from the Maquelab area in the Oecusse enclave, west of Timor-Leste, where no mineralization had been reported before. The geochemical characteristics of stream sediments in Maquelab area drainage basins, located in NW of Oecusse enclave, Timor-Leste, were investigated in order to establish the geochemical baseline conditions prior to any type of new mineral occurrences. Stream sediments demonstrated a different chemical composition with elevated values mainly for Cr (49–12,520 mg kg−1), Ni (11.6–863 mg kg−1) and Co (19.8–77.1 mg kg−1) which was not expected going by the present geological cartography of the area where the existence of ultramafic rocks is not supported. Principal component analysis (PCA) was used after centered log-ratio (CLR) transformation of data that allowed for the observance of different compositional groupings and the identification of the drainage basins they represented. Aided by the stream sediments geochemical results, a geological recognition of the area was then made, which allowed for the discovery of a new ultramafic complex, consisting of dunites, peridotites and serpentinites, containing metamorphic rocks, predominantly calc-silicate, basalts and gabbros. This complex is named the Maquelab Complex due to its proximity to this village. Inside the peridotitic rocks, small boulders of massive chromite with about 56% Cr2O3 were also found.

The intensity of chemical decomposition increases with rainfall and temperature, being extreme under equatorial climate, but in tectonically active regions it can be limited by the rapid erosion of surface material when weathering reactions are still incomplete This paper presents mineralogical and geochemical data from weathering mantles exposed on the equatorial mountainous region of Maubisse (East Timor). Two major groups of regoliths, with contrasting Si-content and associated with different parent rocks, are discriminated by non-mobile elements contents. Although partially inherited from parent rock, the geochemistry (e.g., the values obtained for multi-element weathering parameters, such as CIA, CIX, MIAo, WIP, and α-indices of element mobility) and diverse clay assemblages with low kaolinite contents are in general indicative of minor weathering intensities despite wet (>2000 mm of annual rainfall) and warm (annual average temperature ~20 °C) conditions. These compositional data show that weathering reactions are not keeping up with physical denudation in this tectonically active region. Weathering intensity depends on local orographic and lithologic features, being highest on basaltic terranes due to the enrichment in weatherable silicates relative to sedimentary successions. The present research demonstrates the extent to which different factors can control regolith composition in mountainous equatorial regions and how the application of multiple compositional parameters can help to untangle the roles played by those factors.

Arsenic is a widely distributed element in marine ecosystems. The main anthropogenic sources of this contaminant are domestic and industrial wastewaters, and since it can be harmful to humans even at low concentrations, it has been ranked as one of the top hazardous substances. Therefore, the analysis of arsenic is an essential task to assess the potential environmental and human health risk associated with sewage discharges. The accumulation of total arsenic on intertidal rocky shore macroalgae exposed to contaminated sewage discharges was measured in five macroalgae species (Asparagopsis armata, Codium sp., Plocamium cartilagineum, Saccorhiza polyschides and Ulva sp.). Differences in the concentrations of arsenic were examined in the seawater and in the macroalgae species. The results showed significantly higher concentrations of arsenic near the sewage discharges in all the species except S. polyschides. Although the information obtained from total arsenic determination is not enough to assess the toxicological risk in the environment, this paper gives an important contribution on contamination risks and helps in choosing potential good biomonitors.

A study was conducted to determine the effect of ethylenediaminetetraacetic acid (EDTA) on phytoextraction potential of radish and cabbage. Plant biomass, photosynthetic pigments, proline and phenolics were significantly affected by the accumulation of heavy metals (HM). The metal uptake potential was increased significantly by the application of EDTA. Target hazard quotient (THQ) associated with exposure of these contaminants to food chain was calculated. Agronomic interventions to increase mineral levels in crops often increases the leaf concentrations only, the mineral concentration in edible portions are not increased at desired level due to low mobility of Zn in phloem. Since the leaves of both these crops are edible and a component of staple vegetarian diet, biofortification through Zn present in soil and its solubilization and mobilization through chelators can be implemented. However in no such instance these crops should be consumed when grown on Pb contaminated soil due to associated hazards.

Uranium-contaminated sites are a worrying environmental issue around the world. Accordingly, several programs for the environmental remediation and rehabilitation of U-contaminated sites have been developed worldwide, in order to prevent its dispersion in the environment. This chapter highlights the U concentrations in water–soil–plant matrices and the efficiency of a heterogeneous set of native terrestrial and aquatic plant species in controlling the environmental U contamination in selected case studies. The uptake of U by plants, combined with other removal processes naturally occurring in ecosystems, constitute a form of natural attenuation of contamination. For example, from the case studies presented in this chapter, the high U accumulation patterns of some aquatic plant species, or a consistent preferential trend of U accumulation in the roots/rhizomes of terrestrial plants, confirm their potential for the phytofiltration of U-contaminated waters or for the phytostabilization of U in the soil/sediment rhizosphere, respectively.

The Mussulo lagoon is a coastal environment located near Luanda, one of the SW African cities that has been growing more rapidly during the last decades. Geochemical, mineralogical, and grain-size data obtained for the lagoon sediments are analyzed together, in order to establish the factors that control the distribution of some potentially toxic elements (PTEs). Sediments from northern location tend to be enriched in feldspar and, despite some variability in grain-size distributions, in fine-grained detrital minerals, southern lagoon sediments display very homogenous grain-size distribution and are enriched in minerals associated with salt precipitation (halite and gypsum). Multivariate statistics reveal a close link between some PTEs, namely Co, Hg, Ni, and Pb, for which an anthropogenic source can be postulated. On the other end, As seems to be associated with natural authigenic precipitation in southern lagoon sectors. Sediments enriched in clay also tend to yield more Fe, Mn, Zn, and Cu, but it is unclear whether their sources are natural or anthropogenic. Hazard indexes calculated for children are higher than 1 for As and Co, indicating potential non-carcinogenic risk. For the other elements, and for adults, there is no potential carcinogenic or non-carcinogenic risk.

The work investigates on the potential of ten mangrove species for absorption, accumulation and partitioning of trace metal(loid)s in individual plant tissues (leaves, bark and root/pneumatophore) at two study sites of Indian Sundarban Wetland. The metal(loid) concentration in host sediments and their geochemical characteristics were also considered. Mangrove sediments showed unique potential in many- fold increase for most metal(loid)s than plant tissues due to their inherent physicochemical properties. The ranges of concentration of trace metal(loid)s for As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn in plant tissue were 0.006-0.31, 0.02-2.97, 0.10-4.80, 0.13-6.49, 4.46-48.30, 9.2-938.1, 0.02-0.13, 9.8-1726, 11-5.41, 0.04-7.64, 3.81-52.20 μg g (-1)respectively. The bio- concentration factor (BCF) showed its maximum value (15.5) in Excoecaria agallocha for Cd, suggesting that it can be considered as a high-efficient plant for heavy metal bioaccumulation. Among all metals, Cd and Zn were highly bioaccumulated in E. agallocha (2.97 and 52.2 μg g (-1) respectively. Our findings suggest that the species may be classified as efficient metal trap for Cd in aerial parts, as indicated by higher metal accumulation in the leaves combined with BCF and translocation factor (TF) values.

Uranium mining is an environmental concern because of runoff and the potential for toxic effects on the biota. To investigate uranium toxicity to freshwater invertebrates, we conducted a 96-h acute toxicity test to determine lethal concentrations (testing concentrations up to 262 mg L−1) for three stream invertebrates: a shredder caddisfly, Schizopelex festiva Rambur (Trichoptera, Sericostomatidae); a detritivorous isopod, Proasellus sp. (Isopoda, Asellidae); and a scraper gastropod, Theodoxus fluviatilis (Gastropoda, Neritidae). Next, we ran a chronic-toxicity test with the most tolerant species (S. festiva) to assess if uranium concentrations found in some local streams (up to 25 μg L−1) affect feeding, growth and respiration rates. Finally, we investigated whether S. festiva takes up uranium from the water and/or from ingested food. In the acute test, S. festiva survived in all uranium concentrations tested. LC50-96-h for Proasellus sp and T. fluviatilis were 142 mg L−1 and 24 mg L−1, respectively. Specimens of S. festiva exposed to 25 μg L−1 had 47% reduced growth compared with specimens under control conditions (21.5 ± 2.9 vs. 40.6 ± 4.9 μg of mass increase animal−1·day−1). Respiration rates (0.40 ± 0.03 μg O2·h−1·mg animal−1) and consumption rates (0.54 ± 0.05 μg μg animal−1·day−1; means ± SE) did not differ between treatments. Under laboratory conditions S. festiva accumulated uranium from both the water and the ingested food. Our results indicate that uranium can be less toxic than other metals or metalloids produced by mining activities. However, even at the low concentrations observed in streams affected by abandoned mines, uranium can impair physiological processes, is bioaccumulated, and is potentially transferred through food webs.

Sewage pollution is a worldwide concern and can result in increasing levels of trace elements in the environment that can pose serious risks both to wildlife and human health. This highlights the importance of studying the role of sewage discharges in the contamination of aquatic systems, especially in rocky shores, since part of our food resources is directly collected from coastal waters. For this purpose, the accumulation of trace elements (Cu, Zn, Pb, Ni, Co, Cd, Fe, Mn, and As) by edible molluscs (Mytilus galloprovincialis, Patella ulyssiponensis, and Phorcus lineatus) was compared between one sewage-impacted area and two reference areas.This study suggests that the concentrations of trace elements in the soft tissues of the selected molluscs can be affected by the presence of sewage discharges, and that limpets seem to be the best bioindicator. Moreover, the sewage pollution increased the concentrations of As in the mollusc species, emphasizing its potential damaging effects on natural syste...

A pot study was conducted to assess the phytoremediation potential of Spinach plants along with their physiological and biochemical response when grown in soil contaminated with heavy metal(loid)s (HMs). Plants were grown under different doses of Pb, Cd and As; and their metal(loid) accumulation efficiency was studied upon harvest; expressed in terms of bioabsorption coefficient (BAC), bioconcentration factor (BCF) and translocation factor (TF). Results showed significant (p ≤ 0.05) difference in physiological and biochemical mechanisms of plants as detected through decrease in concentration of cellular constituents (pigments, carbohydrates, total nitrogen content); and increase in antioxidants (both enzymatic and non-enzymatic). Despite of accumulating high amount of HMs in tissues, no visible signs of toxicity were seen; and hence the efficient survival and defense mechanism shown by spinach plants conclude that they are a viable option to be used for phytoremediation of sites contaminated with Cd and Pb. Since the content of Cd and Pb in edible part was higher than safe limits prescribed by USEPA, the present investigation also highlights the ecological hazards that may result upon cultivation of spinach in contaminated soil for agricultural purpose; or its accidental exposure to food chain when grown for phytoremediation.

A study was undertaken to determine Uranium concentrations in water and aquatic plants in the uraniferous region of Beiras, Central Portugal. Samples were collected from running water (n = 200) at places where aquatic species were observed. Plant samples were collected from 28 species of submerged, free-floating and rooted emergent plants including 2 bryophytes and 1 pteridophyte. Uranium concentrations in surface waters ranged from 0.23 to 1217 μg L − 1 . The aquatic plant species studied, including several previously untested species, exhibited the ability to accumulate U in concentrations many times that of the ambient water. In general submerged plants exhibited higher U content followed by rooted emergent and free floating species. The highest U concentrations were observed in the bryophyte Fontinalis antipyretica (up to 4979 mg kg − 1 ) followed by Callitriche stagnalis (1963 mg kg − 1 ), Callitriche hamulata (379 mg kg − 1 ), Ranunculus peltatus subsp. saniculifolius (243 mg kg − 1 ), Callitriche lusitanica (218 mg kg − 1 ), and Ranunculus trichophyllus (65.8 mg kg − 1 ). In two out of three rooted emergent species U seemed to be preferentially partitioned in rhizome/roots with highest rhizome U content recorded in Typha latifolia (380 mg kg − 1 ). Among the free-floating species, the highest U content (42.5 mg kg − 1 ) was seen in Lemna minor . The bryophyte F. antipyretica and Callitrichaceae members seem to be promising candidates for the development of phytofiltration methodologies based on U accumulation, abundance and biomass production.

This study examines the geochemical and mineralogical variations in the ferruginous mineralisations that crop out within Grotta della Monaca, which is considered to be the most striking and best known example of a prehistoric iron mine-cave from the southern Apennines (Calabria, Italy). Previous archaeological research identified three local and distinct ancient exploitation phases of these ferruginous mineralisations: (1) an Upper Palaeolithic phase; (2) a Late Neolithic phase; and (3) a post-Medieval phase. These materials, which have various forms of complex mineralogical admixtures and range in colour from yellow-orange to red and darker brown shades, mainly consist of iron oxides/hydroxides (essentially goethite and lepidocrocite), which are often mixed with subordinate and variable amounts of other matrix components (carbonates, sulphates, arsenates, silicates and organic matter). Such ferruginous mineralisations generally correspond to geochemically heterogeneous massive dyke/vein/mammillary/stratiform facies that are exposed within the local caves along open fractures and inclined bedding planes and that partially cover cave wall niches/notches/pockets and ceiling cupolas/holes. Selected samples/sub-samples are analysed through a multi-technique approach with a handheld portable X-ray Fluorescence, X-ray Diffraction, micro-Raman and Fourier Transform Infrared spectroscope (both conventional and attenuated total reflection), which is combined with subsequent multivariate statistical analysis of the elemental concentration data. The geochemical and mineralogical results are used to individualise similar compositional clusters. As expected, the identified groups, each of which has very specific geochemical-mineralogical "fingerprints" and spatial distributions, enable us to identify the sampled ferruginous mineralisations. These specific mineral resources can be compared to similar raw materials that are found in other neighbouring archaeological sites, with obvious implications toward understanding local exploitation strategies through time and the exchanges and kinship networks of these materials.

The distribution of 14 rare earth elements, Th and U was studied in streams of the study area at 21 sites. Aquatic mosses are known to accumulate even metabolically nonessential or toxic metals in concentrations much higher than their aqueous environment due to their unique morphology and physiology. Thus, the capacity of metal amplification in four aquatic mosses (Fontinalis squamosa, Brachythecium rivulare, Platyhypnidium riparioides and Thamnobryum alopecurum) was also evaluated as a potential bioindicator/biomonitoring tool. Thirteen REEs (0.001–2.81 μg L−1) and U were detected in the stream water. Mean content of lighter rare earth elements (LREEs) was higher than that of heavier rare earth elements (HREEs). Fourteen REEs and two actinides were detected in moss samples, including Yb and Th which were below detection level in water samples. LREE uptake (0.17–12.2 mg kg−1) was greater than HREE uptake (0.02–0.78 mg kg−1) in all mosses. Uptake of LREEs was observed in the order: B. rivulare >T. alopecurum >F. squamosa >P. riparioides and that of HREEs in the order: T. alopecurum >B. rivulare >F. squamosa >P. riparioides. Mean U content (0.68–1.62 mg kg−1) in the mosses was found in the order: B. rivulare >F. squamosa >T. alopecurum >P. riparioides. Th content ranged from 0.4 to 2.36 mg kg−1 in the order: B. rivulare >T. alopecurum >P. riparioides >F. squamosa. One-way ANOVA indicated a statistically significant difference (P ≤ 0.01) in mean concentrations of all elements (individually) in moss samples except for U. Highest bioconcentration factors of six REEs each were observed in B. rivulare (La, Ce, Sm, Eu, Tb and Dy) and T. alopecurum (Nd, Gd, Ho, Er, Tm and Lu). The highest BCFs for Pr and U were obtained in F. squamosa and P. riparioides, respectively. These species hold promise for biomonitoring studies in the future.

Leigh syndrome (LS) is a rare, progressive neurodegenerative mitochondrial disorder of infancy. It is a genetically heterogeneous disease. The mutations in SURF1 gene are the most frequently known cause. Here two cases of LS likely caused by SURF1 gene variants are reported: a 39-year-old male patient with a novel homozygous deletion (c.-11_13del), and a case of a 6-year-old boy with the same deletion and a nonsense mutation (c.868dupT), both in heterozygosity. Blue native PAGE showed absence of assembled complex IV. This is the first report of a variant that may abolish the SURF1 gene initiation codon in two LS patients. info:eu-repo/semantics/publishedVersion

Human activities such as mining have contributed substantially to the increase of metals in aquatic environments worldwide. These metals are bioaccumulated by aquatic organisms and can be biomagnified along trophic webs. The dispersal of contaminants from water to land has been little investigated, even though most aquatic invertebrates in streams have aerial stages. We used field and laboratory approaches to investigate the effects of arsenic pollution on stream invertebrate assemblages, and its bioaccumulation, biomagnification and trophic transfer from aquatic to terrestrial environments by emergent insects. We conducted the study in an arsenic-impacted stream (40μgL-1 As at the most polluted site) and a reference stream (0.3μgL-1 As). Invertebrate abundance and richness were lowest at the most impacted site. Arsenic in biofilm and in invertebrates increased with the arsenic content in the water. The highest arsenic accumulators were bryophytes (1760μgg-1), followed by the biofilm (449μgg-1) and shredder invertebrates (313μgg-1); predators had the lowest arsenic concentration. Insects emerging from water and spiders along streambanks sampled from the reference and the impacted stream did not differ in their body arsenic concentrations. In the laboratory, the shredder Sericostoma vittatum had reduced feeding rates when exposed to water from the impacted stream in comparison with the reference stream (15.6 vs. 19.0mg leaves mg body mass-1 day-1; p

The uptake of arsenic and other metals (iron, manganese, copper, zinc, lead, nickel and tungsten) by Pinus pinaster Aiton (the maritime pine tree) growing in soils and tailings around an abandoned mine (northern Portugal) was investigated. Aerial parts of Pinus pinaster trees were sampled from three substrate areas: a background area, in mine contaminated soils and in tailings. Vegetation material was separated into needles and stems and subdivided into tissues of different maturities (1-, 2-, 3- and 4-years-old). The sampling of the substrate in each area was also undertaken. In general, vegetation concentrations were strongly related to substrate concentrations. The results show that the contents of several elements depend as much on the plant organ as on the age of the tissue. For the researched elements, this species shows a great variability in behavior depending on the age of the organ. The data indicate that the older needles constitute the best samples for use in a conjunct biogeochemical analysis of these elements.

The effect of the glass industry on soil metal characterization was assessed at five test sites at five successive distances in a semi-arid area. A comprehensive profile of Zn, Cd, Pb, Ni, Cu, and As levels in soils was obtained. The spatial distribution patterns of integrated contamination indices for these metals show a similar decreasing trend in distribution as we move further from the industrial cluster. There was significant correlation among individual heavy metal concentrations in the soil samples. Integrated contamination indices indicate that 64% of the sites were in the high contamination range and 28% were in the moderate contamination range. A statistically significant difference (P ≤ 0.001) was obtained for each metal on comparing mean metal content among soil samples. Phytoremedial potential of 12 native plant species was also evaluated. Individual elements displayed remarkably different patterns of accumulation in soils as well as plants. Plants established limited capabilities in mobilizi...

Total concentrations of chemical elements in soils may not be enough to understand the mobility and bioavailability of the elements. It is important to characterise the degree of association of chemical elements in different physical and chemical phases of soil. Another geochemical characterisation methodology is to apply sequential selective chemical extraction techniques. A seven-step sequential extraction procedure was used to investigate the mobility and retention behaviour of Al, Fe, Mn, Cu, Zn, Pb, Cr, Co, Ni, Mo, Cd, Bi, Sn, W, Ag, As and U in specific physical–chemical and mineral phases in mine tailings and soils in the surroundings of the abandoned Ervedosa mine. The soil geochemical data show anomalies associated with mineralised veins or influenced by mining. Beyond the tailings, the highest recorded concentrations for most elements are in soils situated in mineralised areas or under the influence of tailings. The application of principal components analysis allowed recognition of (a) element associations according to their geochemical behaviour and (b) distinction between samples representing local geochemical background and samples representing contamination. Some metal cations (Mn, Cd, Cu, Zn, Co, Cr, Ni) showed important enrichment in the most mobilisable and bioavailable (i.e., water-soluble and exchangeable) fractions due likely to the acidic conditions in the area. In contrast, oxy-anions such as Mo and As showed lower mobility because of adsorption to Fe oxy-hydroxides. The residual fraction comprised largest proportions of Sn and Al and to a lesser extent Zn, Pb, Ni, Cr, Bi, W, and Ag, which are also present at low concentrations in the bioavailable fractions. The elements in secondary mineral phases (mainly Fe, Mn, Cu, Zn, Cd, Pb, W, Bi, Mo, Cr, Ni, Co, As and U) as well as in organic matter and sulphides are temporarily withheld, suggesting that they may be released to the environment by changes in physico-chemical conditions.

Root and shoot samples of Prosopis juliflora were assessed for their heavy metal content to evaluate the species as a green solution to decontaminate soils contaminated with lead and cadmium. The highest uptake of both the metals was observed in plants from industrial sites. Sites with more anthropogenic disturbance exhibited reduced chlorophyll levels, stunted growth, delayed and shortened reproductive phase. The ratios of lead and cadmium in leaves to lead and cadmium in soil were in the range of 0.62-1.46 and 0.55-1.71, respectively. Strong correlation between the degree of contamination and concentrations of lead and cadmium in plant samples identifies P. juliflora as an effective heavy metal remediator coupled with environmental stress.

Regulatory limits for chemicals and ecological risk assessment are usually based on the effects of single compounds, not taking into account mixture effects. The ecotoxicity of metal-contaminated sludge may, however, not only be due to its metal content. Both the sludge matrix and the presence of other toxicants may mitigate or promote metal toxicity. To test this assumption, the toxicity of soils recently amended with an industrial sludge predominantly contaminated with chromium, copper, nickel, and zinc and soils freshly spiked with the same mixture of metals was evaluated through earthworm (Eisenia andrei) and collembolan (Folsomia candida) reproduction tests. The sludge was less toxic than the spiked metal mixture for E. andrei but more toxic for F. candida. Results obtained for the earthworms suggest a decrease in metal bioavailability promoted by the high organic matter content of the sludge. The higher toxicity of the sludge for F. candida was probably due to the additive toxic effect of other pollutants. © 2011 Elsevier Inc.

This study aimed to evaluate short-term earthworm-induced changes in the availability of metals applied to soil directly (metal-spiked) or via an organic matrix (sludge-amended). A laboratory experiment was performed using destructive sampling of microcosms filled with agricultural soil. A concentration gradient of industrial sludge contaminated predominantly with Cr, Cu, Ni, and Zn, and a soil freshly spiked with the same metal concentrations were applied on top of the soil columns. Individuals of Dendrobaena veneta (mimicking a realistic density of 500 earthworms per m 2 ) were introduced in half of the replicates of each treatment. Total and 0.01 M CaCl 2 extractable metal concentrations were measured in soil after 0, 3, 6 and 12 weeks and metal concentrations in earthworms and percolates were measured after 3, 6, and 12 weeks. Earthworm activity did not affect metal availability of any treatment over time, but Ni and Cu concentrations in D. veneta were higher at the highest treatment levels. Earthworm Zn concentrations were similar in all treatments while Cr concentrations increased with increasing soil total metal content only for sludge treatments. Existing relationships of earthworm metal concentrations with total metal content in soil, taken from the literature, were not able to predict the metal levels measured in D. veneta . Results demonstrated that although over 12 weeks earthworm activity did not affect metal availability in soil, their burrowing activities did influence the metal concentrations of percolates over time.

The presence of aquatic hyphomycetes has been reported for several heavy metal-contaminated waters. Tolerance probably is one adaptation to coping with heavy metals. To help clarify this issue strains of two species of aquatic hyphomycetes (Tricladium splendens Ingold and Varicosporium elodeae Kegel) were isolated from a reference stream and a stream contaminated with heavy metals and grown on malt extract agar prepared with reference and contaminated water to characterize colony morphology, growth rate, growth inhibition and interaction among species and strains. In V. elodeae the morphology of colonies differed between strains. Colony diameter increased linearly over time with growth rates being lower for strains isolated from contaminated than from reference streams (mostly for V. elodeae). Strains from the contaminated stream grew faster in medium prepared with contaminated water than in medium prepared with reference water, while for strains from the reference stream there was no significant difference in growth rates on the two media. In interacting isolates radial growth toward the opposing colony was generally lower than toward the dish edge. Percentage growth inhibition was higher for isolates in intraspecific interactions (13-37%) than in interspecific interactions (3-27%). However differences in growth inhibition experienced by interacting isolates were observed only in three cases out of 16. The difference between the percentage inhibition caused and experienced by a given isolate was highest in interactions involving isolates with distinct growth rates. Our results suggest that strains from the reference stream tolerate heavy metals while strains from the contaminated stream seem to be adapted to contaminated waters. We hypothesize that in natural environments fungal species-specific limits of tolerance to metal contamination might determine an abrupt or gradual response of the original fungal community to mine pollution giving origin to a poorer fungal community dominated by adapted strains with distinct functional efficiency.

We investigated the involvement of mitochondrial-dependent apoptosis in Huntington's disease (HD) vs. control (CTR) cybrids, obtained from the fusion of human platelets with mitochondrial DNA-depleted NT2 cells, and further exposed to 3-nitropropionic acid (3-NP) or staurosporine (STS). Untreated HD cybrids did not exhibit significant modifications in the activity of mitochondrial respiratory chain complexes I-IV or in mtDNA sequence variations suggestive of a primary role in mitochondrial susceptibility in the subpopulation of HD carriers studied. However, a slight decrease in mitochondrial membrane potential and increased formation of intracellular hydroperoxides was observed in HD cybrids under basal conditions. Furthermore, apoptotic nuclei morphology and a moderate increase in caspase-3 activation, as well as increased levels of superoxide ions and hydroperoxides were observed in HD cybrids upon 3-NP or STS treatment. 3-NP-evoked apoptosis in HD cybrids involved cytochrome c and AIF release from mitochondria, which was associated with mitochondrial Bax translocation. CTR cybrids subjected to 3-NP showed increased mitochondrial Bax and Bim levels and the release of AIF, but not cytochrome c, suggesting a different mode of cell death, linked to the loss of membrane integrity. Additionally, increased mitochondrial Bim and Bak levels, and a slight release of cytochrome c in untreated HD cybrids may help to explain their moderate susceptibility to mitochondrial-dependent apoptosis.

Phytoremediation potential of uranium (U) was investigated by submerged, free-floating and rooted emergent native aquatic macrophytes inhabiting along the streams of Horta da Vilariça, a uraniferous geochemical region of NE Portugal. The work has been undertaken with the following objectives: (i) to relate the U concentrations in water-sediment-plant system; and (ii) to identify the potentialities of aquatic plants to remediate U-contaminated waters based on accumulation pattern. A total of 25 plant species culminating 233 samples was collected from 15 study points along with surface water and contiguous sediments. Concentrations of U showed wide range of variations both in waters (0.61-5.56 μg L(-1), mean value 1.98 μg L(-1)) and sediments (124-23,910 μg kg(-1), mean value 3929 μg kg(-1)) and this is also reflected in plant species examined. The plant species exhibited the ability to accumulate U several orders of magnitude higher than the surrounding water. Maximum U concentrations was recorded in the bryophyte Scorpiurium deflexifolium (49,639 μg kg(-1)) followed by Fontinalis antipyretica (35,771 μg kg(-1)), shoots of Rorippa sylvestris (33,837 μg kg(-1)), roots of Oenanthe crocata (17,807 μg kg(-1)) as well as in Nasturtium officinale (10,995 μg kg(-1)). Scorpiurium deflexifolium displayed a high bioconcentration factor (BF) of ∼2.5 × 10(4) (mean value). The species Fontinalis antipyretica, Nasturtium officinale (roots) and Rorippa sylvestris (shoots) exhibited the mean BFs of 1.7 × 10(4), 5 × 10(3) and 4.8 × 10(3) respectively. Maximum translocation factor (TF) was very much pronounced in the rooted perennial herb Rorippa sylvestris showing extreme ability to transport U for the shoots and seems to be promising candidate to be used as bioindicator species.

This work constitutes a general description of the results obtained in native aquatic plant species from Portugal (South Western Europe), for the assessment of the potential for phytofiltration techniques of multielement contaminated water. Uptake patterns for metal(loid)s studied indicate the following features: Uranium accumulation in the range of 243–4979 mg/kg (DW) in Fontinalis antipyretica, Callitriche stagnalis, Callitriche hamulata, Callitriche lusitanica, and Ranunculus peltatus; Arsenic concentration from 346 to 2346 mg/kg in C. lusitanica, C. brutia, Lemna minor, Azolla caroliniana, R. trichophyllus, C. stagnalis, and F. antipyretica; Lead from 90.5 to 1104 mg/kg in R. trichophyllus, rhizomes/roots of Typha latifolia, L. minor, Spirodela polyrrhiza, and Myriophyllum spicatum; Copper from 81.8 to 161 mg/kg in C. lusitanica, C. hamulata, R. trichophyllus, and C. stagnalis; and Zinc from 900 to 34,162 mg/kg in L. minor, Lemanea fluviatilis, C. lusitanica, C. brutia, R. trichophyllus, F. antipyretica, and C. stagnalis. The abundance of some of these plant species, their biomass, relatively high bioproductivity, and their ability to accumulate several toxic elements collectively indicates their potential for the development of phytofiltration methodologies, either in monoculture systems or in combined systems representing natural ecosystems.

The present study highlights the uranium (U) concentrations in water-soil-plant matrices and the efficiency considering a heterogeneous assemblage of terrestrial and aquatic native plant species to act as the biomonitor and phytoremediator for environmental U-contamination in the Sevilha mine (uraniferous region of Beiras, Central Portugal). A total of 53 plant species belonging to 22 families was collected from 24 study sites along with ambient soil and/or water samples. The concentration of U showed wide range of variations in the ambient medium: 7.5 to 557mgkg(-1) for soil and 0.4 to 113μgL(-1) for water. The maximum potential of U accumulation was recorded in roots of the following terrestrial plants: Juncus squarrosus (450mgkg(-1) DW), Carlina corymbosa (181mgkg(-1) DW) and Juncus bufonius (39.9mgkg(-1) DW), followed by the aquatic macrophytes, namely Callitriche stagnalis (55.6mgkg(-1) DW) Lemna minor (53.0mgkg(-1) DW) and Riccia fluitans (50.6mgkg(-1) DW). Accumulation of U in plant tissues exhibited the following decreasing trend: root>leaves>stem>flowers/fruits and this confirms the unique efficiency of roots in accumulating this radionuclide from host soil/sediment (phytostabilization). Overall, the accumulation pattern in the studied aquatic plants (L. minor, R. fluitans, C. stagnalis and Lythrum portula) dominated over most of the terrestrial counterpart. Among terrestrial plants, the higher mean bioconcentration factor (≈1 in roots/rhizomes of C. corymbosa and J. squarrosus) and translocation factor (31 in Andryala integrifolia) were encountered in the representing families Asteraceae and Juncaceae. Hence, these terrestrial plants can be treated as the promising candidates for the development of the phytostabilization or phytoextraction methodologies based on the accumulation, abundance and biomass production.

Tree species growing on tailings and mine-contaminated soils show tolerance to imposed stress conditions (metal contamination and nutrient deficiency) and can fulfill the objectives of stabilization, pollution attenuation, and visual improvement. A few trees, of the Pinus , Eucalyptus , and Quercus species, found in tailings and contaminated soils in abandoned mines of Portugal, show accumulation of different metals in the above-ground tissues. Hence these communities tolerant to toxic trace elements play a major role in remediation of degraded mine soils. Furthermore, these plants could grow and propagate in substrata with low nutrient conditions, which would be a great advantage in the revegetation of mine tailings. It was also observed that despite lower accumulation when compared to herbaceous and shrub species, trees of the studied regions can be very effective for metals phytoextraction and phytostabilization due to their higher biomass and bioproductivity, especially when established in the less contaminated soils on the peripheral zone of the studied areas. Furthermore, when the metal concentrations in the above-ground parts were maintained at low levels, the biomass can be used to obtain economic value.

The selection of trace element tolerant species is a key factor to the success of remediation of degraded mine soils. Mining activities generate a large amount of waste rocks and tailings, which get deposited at the surface. The degraded soils, the waste rocks and tailings are often very unstable and will become sources of pollution. The direct effects will be the loss of cultivated land, forest or grazing land, and the overall loss of production. The indirect effects will include air and water pollution and siltation of rivers. These will eventually lead to the loss of biodiversity, amenity and economic wealth. Restoration of a vegetation cover can fulfil the objectives of stabilization, pollution control, visual improvement and removal of threats to human beings. Thus, remediation of mine spoils/tailings and biogeochemical prospecting would rely on the appropriate selection of plant species.Plant community responds differently on their ability to uptake or exclude a variety of metals. In this work, plant species were sampled from all populations established in an abandoned copper mine of São Domingos, SE Portugal. Plants belonging to 24 species, 16 genera and 13 families were collected from the degraded copper mine of São Domingos. Plant samples were analysed for total Ag, As, Cu, Ni, Pb, and Zn. The highest concentrations of metals in soils dry matter were 11217.5 mg Pb kg−1, 1829 mg Cu kg−1, 1291 mg As kg−1, 713.7 mg Zn kg−1, 84.6 mg Cr kg−1, 54.3 mg Co kg−1, 52.9 mg Ni kg−1 and 16.6 mg Ag kg−1. With respect to plants, the higher concentrations of Pb and As were recorded in the semi-aquatic species Juncus conglomeratus with 84.8 and 23.5 mg kg−1 dry weight (DW), Juncus efusus with 22.4 and 8.5 mg kg−1 DW, and Scirpus holoschoenus with 51.7 and 8.0 mg kg−1 DW, respectively. Thymus mastichina also showed high content of As in the aboveground parts, 13.6 mg kg−1 DW. Overall, the results indicate accumulation of various metals by different plant species, with some of these metals being partitioned to the shoots. Environmental implications of these observations are discussed. Keywords: Trace metals, Metal-tolerant plant community, Copper mine, Portugal

Contaminated soils and residues can be remediated by various methods, such as: removal, isolation, incineration, solidification/stabilization, vitrification, thermal treatment, solvent extraction, chemical oxidation, etc. These methods have the disadvantage of being very expensive and in some cases, they involve the movement of contaminated materials to treatment sites thus, adding risks of secondary contamination [1-3]. Therefore, currently preference is being given to in situ methods that are less environmentally disruptive and more economical. In this context, biotechnology offers phytoremediation techniques as a suitable alternative.

This study presents the results of laboratory experiments, including a prototype phytofiltration system, to reduce the uranium (U) concentration in contaminated waters. The species Callitriche stagnalis Scop., Potamogeton natans L. and Potamogeton pectinatus L. of the native plant community of the uraniferous Beiras (Central Portugal) region were selected because they are autochthonous and they show high accumulation levels and/or high biomass production. The installed prototype consists of a closed circuit of channels. The system was initially contaminated with 500 μg/L of U as uranyl. The performance of this system was very effective. The U concentration in the water dropped to 220 μg/L in 24 h and after two weeks it had decreased to 72.3 μg/L. The U concentration increased in C. stagnalis from 0.98 to 1567 mg/kg, in P. natans from 3.46 to 270.9 mg/kg and in P. pectinatus from 2.63 to 1588 mg/kg. The results show the effectiveness of these plants in removing U from the water.

The rapid industrialization and intensive agricultural activities over the last few decades have resulted in accumulation of various pollutants in the environment, which are distributed over wide areas by means of air and water. This has caused visible detrimental effects to the ecosystem and consequences to human health. Today, many soils throughout the world have undesirably high concentrations of heavy metals. These include lead (Pb), cadmium (Cd), zinc (Zn), mercury (Hg), arsenic (As), silver (Ag), chromium (Cr), copper (Cu), iron (Fe), and the platinum group elements. At low or background concentrations, heavy metals are not pollutants. They occur naturally in the environment due to their presence in bedrocks. Some heavy metals such as Zn and Cu are also essential micronutrients for living organisms. Therefore, the term heavy metal pollution refers to heavy metal levels that are abnormally high relative to normal background levels. All heavy metals at high concentration have strong toxic effects and are regarded as environmental pollutants.