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1.
Environ Res ; 192: 110241, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32980301

RESUMO

Since cacao beans accumulate Cd in high levels and restrictions have been imposed on safe levels of chocolate consumption, concern about whether or not cacao trees store other toxic elements seems to be inevitable. Following a previous study in Ecuador examining Cd content in five cacao varieties collected in pristine areas and in places impacted by oil activities, we present here the concentrations of 11 trace elements (TEs) (As, Ba, Co, Cu, Cr, Mo, Mn, Ni, Pb, V and Zn) in soils, cacao tissues (leaves, pod husks, beans) and cocoa liquor (CL). Several TEs showed concentrations in topsoils above the Ecuadorian limits, and may have a mixed natural and anthropogenic origin. Ba and Mo concentrations in cacao tissues are slightly higher than those reported in other surveys, but this was not the case for toxic elements (As and Pb). TE contents are lower in CL, than in beans, except for Pb and Co, but no risk was identified for human health. Compared with control areas, Enrichment Factors were below 2 in impacted areas, except for Ba. Transfer factors (from soils to cacao) indicated that cacao does not accumulate TEs. A positive correlation was found between Cd and Zn in topsoils and cacao tissues for the CCN-51 variety, and between Cd and Ni for the Nacional variety. Identifying patterns of TE distribution and potential interactions in order to explain plant internal mechanisms, which is also dependent on the cacao variety, is a difficult task and needs further research.


Assuntos
Cacau , Metais Pesados , Poluentes do Solo , Oligoelementos , Cádmio/análise , Equador , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Solo , Poluentes do Solo/análise , Oligoelementos/análise
2.
Environ Geochem Health ; 43(11): 4741-4757, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33974199

RESUMO

In French Guiana were detected high lead (Pb) levels in blood of Amerindian people. Lead exposure is a serious hazard that can affect the cognitive and behavior development. People can be exposed to Pb through occupational and environmental sources. Fingerprinting based on stable Pb isotopes in environmental media is often used to trace natural and anthropogenic sources but is rarely paired with blood data. The objective of this study was to determine the main factors associated with high Blood Lead Levels (BLL). Soil, manioc tubers, food bowls, beverages, wild games, lead pellets and children blood were sampled in small villages along the Oyapock River. children BLL ranged between 5.7 and 35 µg dL-1, all exceeding 5 µg dL-1, the reference value proposed in epidemiologic studies for lead poisoning. Among the different dietary sources, manioc tubers and large game contained elevated Pb concentrations while manioc-based dishes were diluted. The isotopes ratios (207Pb/206Pb and 208Pb/206Pb) of children blood overlapped these of lead shots and meals. These first results confirm for the first time, the diary consumption of manioc-based food as the main contributor to Amerindian children's BLL in French Guiana, but don't exclude the occasional exposure to lead bullets by hunting activities. This is a specific health concern, since previous studies have shown that these same villagers present high levels of mercury (Hg). These communities are indeed subject to a double exposure to neurotoxic metals, Hg and Pb, both through their diet. The farming activity is based on manioc growing, and explaining that this ancestral practice can induce serious health risks for the child's development may seriously affect their food balance and cultural cohesion.


Assuntos
Intoxicação por Chumbo , Mercúrio , Criança , Exposição Ambiental/análise , Guiana Francesa , Humanos , Chumbo/análise
3.
Environ Sci Technol ; 51(9): 5242-5251, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28383257

RESUMO

Throughout the world, urban agriculture supplies fresh local vegetables to city populations. However, the increasing anthropogenic uses of metal-containing nanoparticles (NPs) such as CuO-NPs in urban areas may contaminate vegetables through foliar uptake. This study focused on the CuO-NP transfer processes in leafy edible vegetables (i.e., lettuce and cabbage) to assess their potential phytotoxicity. Vegetables were exposed via leaves for 5, 10, or 15 days to various concentrations of CuO-NPs (0, 10, or 250 mg per plant). Biomass and gas exchange values were determined in relation to the Cu uptake rate, localization, and Cu speciation within the plant tissues. High foliar Cu uptake occurred after exposure for 15 days for lettuce [3773 mg (kg of dry weight)-1] and cabbage [4448 mg (kg of dry weight)-1], along with (i) decreased plant weight, net photosynthesis level, and water content and (ii) necrotic Cu-rich areas near deformed stomata containing CuO-NPs observed by scanning electron microscopy and energy dispersive X-ray microanalysis. Analysis of the CuO-NP transfer rate (7.8-242 µg day-1), translocation of Cu from leaves to roots and Cu speciation biotransformation in leaf tissues using electron paramagnetic resonance, suggests the involvement of plant Cu regulation processes. Finally, a potential health risk associated with consumption of vegetables contaminated with CuO-NPs was highlighted.


Assuntos
Agricultura , Cobre/toxicidade , Microanálise por Sonda Eletrônica , Lactuca/metabolismo , Nanopartículas Metálicas/toxicidade , Óxidos
4.
Environ Geochem Health ; 38(3): 869-83, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26387097

RESUMO

Selenium is a micronutrient needed by all living organisms including humans, but often present in low concentration in food with possible deficiency. From another side, at higher concentrations in soils as observed in seleniferous regions of the world, and in function of its chemical species, Se can also induce (eco)toxicity. Root Se uptake was therefore studied in function of its initial form for maize (Zea mays L.), a plant widely cultivated for human and animal food over the world. Se phytotoxicity and compartmentalization were studied in different aerial plant tissues. For the first time, Se oral human bioaccessibility after ingestion was assessed for the main Se species (Se(IV) and Se(VI)) with the BARGE ex vivo test in maize seeds (consumed by humans), and in stems and leaves consumed by animals. Corn seedlings were cultivated in hydroponic conditions supplemented with 1 mg L(-1) of selenium (Se(IV), Se(VI), Control) for 4 months. Biomass, Se concentration, and bioaccessibility were measured on harvested plants. A reduction in plant biomass was observed under Se treatments compared to control, suggesting its phytotoxicity. This plant biomass reduction was higher for selenite species than selenate, and seed was the main affected compartment compared to control. Selenium compartmentalization study showed that for selenate species, a preferential accumulation was observed in leaves, whereas selenite translocation was very limited toward maize aerial parts, except in the seeds where selenite concentrations are generally high. Selenium oral bioaccessibility after ingestion fluctuated from 49 to 89 % according to the considered plant tissue and Se species. Whatever the tissue, selenate appeared as the most human bioaccessible form. A potential Se toxicity was highlighted for people living in seleniferous regions, this risk being enhanced by the high Se bioaccessibility.


Assuntos
Disponibilidade Biológica , Selênio/metabolismo , Selênio/toxicidade , Zea mays/metabolismo , Animais , Contaminação de Alimentos , Humanos , Componentes Aéreos da Planta/química , Raízes de Plantas/química , Sementes/química , Selênio/química , Zea mays/crescimento & desenvolvimento
5.
J Environ Sci (China) ; 46: 16-27, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27521932

RESUMO

At the global scale, foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere. However, the kinetics of metal uptake, translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles (PM). Different leafy vegetables (lettuces and cabbages) cultivated in RHIZOtest® devices were, therefore, exposed in a greenhouse for 5, 10 and 15days to various PbO PM doses. The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration. A significant Pb accumulation in leaves (up to 7392mg/kg dry weight (DW) in lettuce) with translocation to roots was observed. Lead foliar exposure resulted in significant phytotoxicity, lipid composition change, a decrease of plant shoot growth (up to 68.2% in lettuce) and net photosynthesis (up to 58% in lettuce). The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage. Air quality needs, therefore, to be considered for the health and quality of vegetables grown in polluted areas, such as certain megacities (in China, Pakistan, Europe, etc.) and furthermore, to assess the health risks associated with their consumption.


Assuntos
Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental , Chumbo/toxicidade , Material Particulado/toxicidade , Folhas de Planta/química , Verduras/química , Agricultura , Poluentes Atmosféricos/análise , China , Cidades , Chumbo/análise , Paquistão , Material Particulado/análise
6.
Environ Res ; 133: 185-94, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24959986

RESUMO

This study proposes global threat scores to prioritize the harmfulness of anthropogenic fine and ultrafine metallic particles (FMP) emitted into the atmosphere at the global scale. (Eco)toxicity of physicochemically characterized FMP oxides for metals currently observed in the atmosphere (CdO, CuO, PbO, PbSO(4), Sb(2)O(3), and ZnO) was assessed by performing complementary in vitro tests: ecotoxicity, human bioaccessibility, cytotoxicity, and oxidative potential. Using an innovative methodology based on the combination of (eco)toxicity and physicochemical results, the following hazard classification of the particles is proposed: CdCl2~CdO>CuO>PbO>ZnO>PbSO(4)>Sb(2)O(3). Both cadmium compounds exhibited the highest threat score due to their high cytotoxicity and bioaccessible dose, whatever their solubility and speciation, suggesting that cadmium toxicity is due to its chemical form rather than its physical form. In contrast, the Sb(2)O(3) threat score was the lowest due to particles with low specific area and solubility, with no effects except a slight oxidative stress. As FMP physicochemical properties reveal differences in specific area, crystallization systems, dissolution process, and speciation, various mechanisms may influence their biological impact. Finally, this newly developed and global approach could be widely used in various contexts of pollution by complex metal particles and may improve risk management.


Assuntos
Poluentes Ambientais/toxicidade , Nanopartículas Metálicas/toxicidade , Metais/toxicidade , Material Particulado/toxicidade , Oligoelementos/toxicidade , Aliivibrio fischeri , Compostos de Cádmio/toxicidade , Linhagem Celular Tumoral , Cobre/toxicidade , Ecotoxicologia/normas , Humanos , Chumbo/toxicidade , Nanopartículas Metálicas/química , Metais/química , Estresse Oxidativo , Óxidos/toxicidade , Material Particulado/química , Medição de Risco , Óxido de Zinco/toxicidade
7.
Environ Geochem Health ; 36(5): 897-909, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24729051

RESUMO

At the global scale, high concentrations of particulate matter (PM) enriched with metal(loid)s are currently observed in the atmosphere of urban areas. Foliar lead uptake was demonstrated for vegetables exposed to airborne PM. Our main objective here was to highlight the health risk associated with the consumption of vegetables exposed to foliar deposits of PM enriched with the various metal(loid)s frequently observed in the atmosphere of urban areas (Cd, Sb, Zn and Pb). Leaves of mature cabbage and spinach were exposed to manufactured mono-metallic oxide particles (CdO, Sb2O3 and ZnO) or to complex process PM mainly enriched with lead. Total and bioaccessible metal(loid) concentrations were then measured for polluted vegetables and the various PM used as sources. Finally, scanning electronic microscopy coupled with energy dispersive X-ray microanalysis was used to study PM-phyllosphere interactions. High quantities of Cd, Sb, Zn and Pb were taken up by the plant leaves. These levels depended on both the plant species and nature of the PM, highlighting the interest of acquiring data for different plants and sources of exposure in order to better identify and manage health risks. A maximum of 2% of the leaf surfaces were covered with the PM. However, particles appeared to be enriched in stomatal openings, with up to 12% of their area occupied. Metal(loid) bioaccessibility was significantly higher for vegetables compared to PM sources, certainly due to chemical speciation changes. Taken together, these results confirm the importance of taking atmospheric PM into account when assessing the health risks associated with ingestion of vegetables grown in urban vegetable crops or kitchen gardens.


Assuntos
Poluentes Atmosféricos/metabolismo , Brassica/metabolismo , Metaloides/metabolismo , Material Particulado/metabolismo , Folhas de Planta/metabolismo , Spinacia oleracea/metabolismo , Cidades , Metaloides/química , Metais Pesados/química , Metais Pesados/metabolismo , Microscopia Eletrônica de Varredura , Material Particulado/análise , Estômatos de Plantas/metabolismo , Espectrometria por Raios X , Verduras
8.
Chemosphere ; 357: 141974, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615955

RESUMO

The former mining district of Salsigne is situated in the Orbiel valley. Until the 20th century, it was the first gold mine in Europe and the first arsenic mine in the world. Rehabilitation has been performed during the 20 years that followed closure of the mines and factories, which led to the accumulation of storage of several million tons of waste in this valley. Nevertheless, a detailed description of the air quality of this area is still missing. The goal of the present study is to evaluate atmospheric contamination in the valley and identify the potential sources of this contamination. Active monitors (particulate matter samplers) and passive bioindicators (Tillandsia usneoides) were placed in strategic sites including remote areas. Over the year 2022, we assessed the air quality using microscopic and spectroscopic techniques, as well as environmental risk indicators to report the level of contamination. Results indicate that the overall air quality in the valley is good with PM10 levels in accordance with EU standards. Elemental concentrations in the exposed plants were lower than reported in the literature. Among the different sites studied, Nartau and La Combe du Saut, corresponding to waste storage and former mining industry sites, were the most affected. Chronic exposure over 1 year was highlighted for Fe, Ni, Cu, Pb, Sb and As. Pollution Load Index and Enrichment Factors, which provided valuable information to assess the environmental condition of the valley's air, suggested that dust and resuspension of anthropogenic materials were the principle sources for most of the elements. Finally, this study also highlights that using T. usneoides could be a convenient approach for biomonitoring of metal (loid)-rich particles in the atmosphere within a former mining area, for at least one year. These results in turn allow to better understand the effects of chronic exposure on the ecosystem.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Mineração , Material Particulado , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , França , Poluição do Ar/estatística & dados numéricos , Material Particulado/análise , Metais/análise , Arsênio/análise , Metais Pesados/análise
9.
Rev Environ Contam Toxicol ; 221: 107-27, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23090631

RESUMO

Zirconium (Zr) is a transition metal that has both stable and radioactive isotopes.This metal has gained significant attention as a major pollutant of concern, partly because it has been prominent in the debate concerning the growing anthropogenic pressure on the environment. Its numerous past and present uses have induced significant soil and water pollution. Zr is generally considered to have low mobility in soils. The behavior of Zr particularly depends on the characteristics of the media in which it exists, and even its presence in the biosphere as a contaminate may affect its behavior. In this chapter, we describe the relationship between the behavior of Zrand its speciation in soils, its uptake and accumulation by plants, its translocation and toxicity inside plants, and mechanisms by which plants detoxify it.Zr is abundant and occurs naturally in the earth's crust. Zr emissions to the atmosphere are increasing from anthropogenic activities such as its use in industry and nuclear reactors. Zr forms various complexes with soil components, which reduces its soil mobility and phytoavailabilty. The mobility and phytoavailabilty of Zr in soil depend on its speciation and the physicochemical properties of soil that include soil pH, texture, and organic contents. Despite having low soil mobility and phytoavailability,amounts of Zr are absorbed by plants, mainly through the root system and can thereby enter the food chain.After plant uptake, Zr mainly accumulates in root cells. Zr does not have any known essential function in plant or animal metabolism. Although little published data are available, we conclude that the phytotoxicity of Zr is generally low.Notwithstanding, Zr can significantly reduce plant growth and can affect plantenzyme activity. When exposed to Zr-induced toxicity, plants possess numerous defense mechanisms to cope with the toxicity. Such strategies include Zr sequestration in plant roots and activation of various antioxidants. Because Zr may have impact on the biosphere, we believe it deserves to be evaluated in supplementary studies that will enhance the understanding of its behavior in soil-plant systems.


Assuntos
Plantas/efeitos dos fármacos , Plantas/metabolismo , Poluentes do Solo/farmacocinética , Zircônio/farmacocinética , Zircônio/toxicidade , Transporte Biológico
10.
Chemosphere ; 287(Pt 2): 132111, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34507147

RESUMO

The mining district of Salsigne in the Orbiel valley (Aude, France) was at one time the first gold mine in Europe and the first arsenic mine in the world. However, no scientific studies have evaluated the magnitude of its environmental impact. In this study, the pedo-geochemical background (PGB) was determined for 14 metal (loid) elements, including As. It appears that the PGB values for As and Sb are relatively high with 44±12 and 0.9±1.2 mg kg-1, respectively, because of the geological particularities of this area. In a second step, these PGB values (normalized with Ti concentrations) were used as local references to determine enrichment factors (EFs) of bed river sediments for the Orbiel River and two of its major tributaries (Gresillou and Russec rivers) collected between November 2018 and July 2020. Results showed that riverine sediments are contaminated by past mining activity and/or current storage areas. If we except the major elements (Fe, Ti and at a lesser extent Mn), we observed that As, Cu, Sb, Pb present the highest concentrations relative to the remaining elements (Cd, Co, V, Ni and Cr). In the case of As, EFs can reach 74 in the Orbiel River, 1000 in the Gresillou River and 27 in the Russec River. These calculations were also performed for sediments transported by the extreme flood of October 14, 2018, that killed 15 people and potentially remobilized contamination in the valley. We observed that the As concentrations of suspended samples from Grésillou and Russec rivers have reached 870 mg kg-1. Finally, the As concentrations measured in the river sediments of this valley are of the same order of magnitude than those published in the literature for environments strongly impacted by mining or mineral processing activities.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Mineração , Rios , Poluentes Químicos da Água/análise
11.
Sci Total Environ ; 852: 158460, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36063937

RESUMO

Phytoliths are microscopic structures made of amorphous opal (opal-A), an amorphous hydrated silica, dispersed within plant tissues and persisting after the decay of the plant. Silicon is known to alleviate metal toxicity in plants, but the role of phytoliths in metal sequestration and detoxification is unclear. Dry ashing, the most common protocol for phytolith extraction, was previously shown to lead to sequestration of metals by the phytoliths; however, the mechanisms of this process remained elusive. The purpose of this study was to evaluate whether the association between metals and phytoliths results from dry ashing or pre-exists in plant tissues. Thus, we compared phytoliths extracted by dry ashing at 700 °C and plant leaves before and after dry ashing. A combination of ICP-MS, XRD, SEM-EDX and Zn-K-edge EXAFS spectroscopy was used to assess elemental concentrations, morphology and crystallography of silica, and chemical status of Zn. Results demonstrated a phase transition from amorphous opal (opal-A) to opal-CT and α-cristobalite, and the sequestration of metal in phytoliths during dry ashing. For Zn, Mn and Pb, a linear relationship was found between the concentration in phytoliths and in leaves. In the phytoliths, Zn was sequestered in silica in tetrahedral configuration. We hypothesize that this association results form a solid-state reaction during ashing, involving a redistribution of Zn from the organic material to the silica, possibly promoted by the release of structural water from amorphous opal throughout the heating procedure. This study improves our understanding of the impact of high temperature treatments on plant biomass and phytoliths. It suggests that Zn toxicity alleviation in plants by silicon does not rely on its sequestration by phytoliths. In natural settings, wild fire events and biomass burning may lead to metal sequestration in low-soluble form, which should be considered in modeling of biogeochemical cycles and in paleoenvironmental studies.


Assuntos
Silício , Zinco , Chumbo , Plantas/química , Dióxido de Silício/química , Água
12.
Front Plant Sci ; 12: 755944, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095944

RESUMO

Even though copper (Cu) is an essential plant nutrient, it can become toxic under certain conditions. Toxic effects do not only depend on soil Cu content, but also on environmental and physiological factors, that are not well understood. In this study, the mechanisms of Cu bioavailability and the homeostasis of Vitis vinifera L. cv. Tannat were investigated under controlled conditions, using stable Cu isotope analysis. We measured Cu concentrations and δ65Cu isotope ratios in soils, soil solutions, roots, and leaves of grapevine plants grown on six different vineyard soils, in a 16-week greenhouse experiment. The mobility of Cu in the soil solutions was controlled by the solubility of soil organic matter. No direct relationship between Cu contents in soils or soil solutions and Cu contents in roots could be established, indicating a partly homeostatic control of Cu uptake. Isotope fractionation between soil solutions and roots shifted from light to heavy with increasing Cu exposure, in line with a shift from active to passive uptake. Passive uptake appears to exceed active uptake for soil solution concentrations higher than 270 µg L-1. Isotope fractionation between roots and leaves was increasingly negative with increasing root Cu contents, even though the leaf Cu contents did not differ significantly. Our results suggest that Cu isotope analysis is a sensitive tool to monitor differences in Cu uptake and translocation pathways even before differences in tissue contents can be observed.

13.
Chemosphere ; 241: 124955, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31604198

RESUMO

Nowadays, atmospheric pollution has a major impact on the human health and the environment, encouraging the development of biomonitors of the air quality over a wide zone. In this study, the relevance of the epiphyte plants Tillandsia usneoides is studied to estimate the transfer of metal(loid)s from a former Zn and Pb mining zone in the Southeast of Spain (Cartagena-La Unión) to the local atmosphere. Biomonitoring was performed by installing plants in 5 sites along a transect from the main mining area to the urban and the coastal zones. An aliquot of plants was collected in every site every 2 months over 1 year. The Tillandsia usneoides have been observed with SEM-EDX, and analysed by ICP-MS to determine trace element concentrations, magnetic susceptibility signals and Zn and Pb isotopes ratios. Results show that atmospheric particles are distributed homogeneously at the plant surface. By comparing elemental contents in Tillandsia usneoides with regard to the values of the geochemical background of the region of Murcia, significant enrichments are observed in the epiphyte plants for Sb, As, Cd, Zn and Pb. The statistical analyses (decentred PCA and PLS) also suggest that the kinetics of dust deposition is slower for the urban and coastal sites compared to the mining sites and highlight an influence of agricultural activities in Cu deposition. The similarity of isotopic compositions (Zn and Pb) between Tillandsia usneoides, soils and atmospheric particles also put in evidence that these plants could be a powerful tool to trace the source of matter in the atmosphere. Finally, this experiment provides new insight to better understand the foliar absorption mechanisms.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Tillandsia/química , Oligoelementos/análise , Poluição do Ar/análise , Atmosfera/análise , Atmosfera/química , Poluição Ambiental/análise , Metais/análise , Mineração , Solo/química , Espanha
14.
Sci Total Environ ; 712: 135595, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31818547

RESUMO

In Southern Europe, soil contamination by heavy metals (HM) due to mining and industrial activities is a long-known problem. Yet, despite soils being widely contaminated through decades, some plants are still able to grow. Some of these plants, like giant reed (Arundo donax) or common reed (Phragmites australis) are capable of accumulating substantial amount of HM. These reeds also contain small silica structures in their shoots, called phytoliths. However, the role of phytoliths in reducing stress caused by these HM remains unknown. The aim of this work is then to determine if phytoliths represent a preferential structure for the bioacccumulation of HM in plants. Therefore, plants from mining-contaminated sites in Spain and France were sampled and HM concentrations in total plant shoots were compared to those in phytoliths for eight metal(oid)s: As, Cd, Cu, Mn, Pb, Sb, Sn and Zn. Results show that Arundo donax and Phragmites australis tend to accumulate Cd, Sb and Sn but limit the uptake of As, Cu, Mn, Pb and Zn in plant shoots despite that the concentration of these HM in soil is quite high. Therefore, reeds appear as tolerant to high metal concentrations in soils, and phytoliths are identified as preferential structures for encapsulation of As, Cu, Mn, Pb and Zn, while Cd, Sb and Sn were mainly found to be accumulated in organic tissues rather than in phytoliths.


Assuntos
Metais Pesados/análise , Biodegradação Ambiental , França , Mineração , Solo , Poluentes do Solo , Espanha
15.
Environ Sci Pollut Res Int ; 26(20): 20052-20063, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30145761

RESUMO

At the global scale, urban agriculture is increasingly developing in cities due to demographic growth and sustainable food concerns. But, urban soils are frequently polluted with metals. In urban gardens, organic matter is also commonly added both to valorize organic household waste and to promote biophysicochemical fertility. As earthworms promote the decomposition and the recycling of soil organic matter, they can also influence the biogeochemical cycle of metals in urban polluted soils. In order to produce safe vegetables in urban areas, it is crucial to highlight the mechanisms involved in complex soil-earthworm-plant ecosystems. An experiment was set up to examine these relationships using lettuce cultivated in controlled conditions with RHIZOtest® devices. Thanks to the RHIZOtest® devices, metal transfer and bioaccessibility were for the first time compared for urban polluted soil without (1-urban soil polluted with Pb, Cd, Cu, and Zn: essential or toxic metals currently found in environment, SNB) and with bioturbation (2-this metal-polluted soil subjected to earthworm bioturbation, SB) and earthworm casts (3-earthworm casts produced in this polluted soil and naturally enriched in organic matter and microorganisms, T). Metal concentration, phytoavailability, and human gastric bioaccessibility were determined in the different samples. Results showed that earthworm bioturbation increased the phytoavailability of all the metals. For the experimental condition SB, the phytoavailability of metals was increased up to 75% compared to SNB. In addition, surprisingly, metal phytoavailability was always superior in SB compared to earthworm casts (T). Moreover, earthworms led to an increase in Zn gastric bioaccessibility up to 10% in the soils in the same way as for phytoavailability, meaning Zn bioaccessibility in SB > T > SNB, whereas it remained unchanged in the lettuces. These data are important to promote sustainable agriculture activities in urban areas; actually, databases concerning different experimental conditions are needed to develop decision support tools.


Assuntos
Lactuca/química , Metais/farmacocinética , Oligoquetos/fisiologia , Poluentes do Solo/farmacocinética , Agricultura/métodos , Animais , Disponibilidade Biológica , Cidades , Exposição Dietética , Ecossistema , Contaminação de Alimentos , Humanos , Lactuca/crescimento & desenvolvimento , Metais/análise , Solo/química , Poluentes do Solo/análise
16.
RSC Adv ; 9(58): 34011-34022, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-35528875

RESUMO

The often high Cd concentrations of cacao beans are a serious concern for producers in Latin America due to the implementation of stricter Cd limits for cocoa products by the European Union in 2019. This is the first investigation to employ coupled Cd isotope and concentration measurements to study soil - cacao systems. Analyses were carried out for 29 samples of soils, soil amendments and cacao tree organs from organic farms in Ecuador that harvest three distinct cacao cultivars. The majority of soils from 0-80 cm depth have very similar δ114/110Cd of about -0.1‰ to 0‰. Two 0-5 cm topsoils, however, have high Cd concentrations coupled with heavy Cd isotope compositions of δ114/110Cd ≈ 0.2%, possibly indicating Cd additions from the tree litter used as organic fertilizer. Whilst cacao leaves, pods and beans are ubiquitously enriched in Cd relative to soils there are distinct Cd isotope signatures. The leaves and pods are isotopically heavier than the soils, with similar Δ114/110Cdleaf-soil values of 0.22 ± 0.07‰ to 0.41 ± 0.09‰. In contrast, the data reveal differences in Δ114/110Cdbean-leaf that may be linked to distinct cacao cultivars. In detail, Δ114/110Cdbean-leaf values of -0.34‰ to -0.40‰ were obtained for Nacional cacao from two farms, whilst CCN-51 hybrid cacao from a third farm showed no fractionation within error (-0.08 ± 0.13‰). As such, further work to investigate whether Cd isotopes are indeed useful for tracing sources of Cd enrichments in soils and to inform genetic efforts to reduce the Cd burden of cocoa is indicated.

17.
Food Chem ; 298: 125033, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260969

RESUMO

Elemental profiles of wines have been used successfully to distinguish their geographical provenience around the world; however, underlying mechanisms are poorly understood. In this study, Ba, Ca, Mg, Mn and Sr contents were determined in 215 wines from several West European wine-growing areas using an easy-to-perform analysis based on ICP-OES. Major environmental and wine-making parameters (soil type as "calcareous" or not, rainfall, temperature and wine color) were used to explain variations within the dataset. The combined effects of wine-making processes (expressed by wine color) and soil type explained 28.5% of total variance. The effect of climatic conditions explained 24.1% of variance and could be interpreted as intensity of drought stress. Finally, carbonate occurrence in soils and climatic conditions systematically influenced the elemental composition of the wines. These findings provide insights into the mechanisms underlying elemental fingerprinting and allow prediction of which wine-growing regions can easily be distinguished based on elemental profiles as a marker of the terroir in viticulture.


Assuntos
Solo/química , Vitis/química , Vinho/análise , Carbonatos/análise , Cor , Bases de Dados Factuais , Europa (Continente) , Análise de Alimentos , Metais/análise , Conceitos Meteorológicos , Chuva
18.
Sci Total Environ ; 690: 1203-1217, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31470483

RESUMO

The unregulated oil exploitation in the Northern Ecuadorian Amazon Region (NEAR), mainly from 1964 to the 90's, led to toxic compounds largely released into the environment. A large majority of people living in the Amazon region have no access to drinking water distribution systems and collects water from rain, wells or small streams. The concentrations of major ions, trace elements, PAHs (polycyclic aromatic hydrocarbons) and BTEX (benzene, toluene, ethylbenzene, xylenes) were analyzed in different water sources to evaluate the impacts of oil extraction and refining. Samples were taken from the NEAR and around the main refinery of the country (Esmeraldas Oil Refinery/State Oil Company of Ecuador) and were compared with domestic waters from the Southern region, not affected by petroleum activities. In most of the samples, microbiological analysis revealed a high level of coliforms representing significant health risks. All measured chemical compounds in waters were in line with national and international guidelines, except for manganese, zinc and aluminum. In several deep-water wells, close to oil camps, toluene concentrations were higher than the natural background while PAHs concentrations never exceeded individually 2 ng·L-1. Water ingestion represented 99% of the total exposure pathways for carcinogenic and non-carcinogenic elements (mainly zinc) in adults and children, while 20% to 49% of the Total Cancer Risk was caused by arsenic concentrations. The health index (HI) indicates acceptable chronic effects for domestic use according the US-EPA thresholds. Nevertheless, these limits do not consider the cocktail effects of metallic and organic compounds. Furthermore, they do not include the social determinants of human exposure, such as socio-economic living conditions or vulnerability. Most (72%) of interviewed families knew sanitary risks but a discrepancy was observed between knowledge and action: religious beliefs, cultural patterns, information sources, experience and emotions play an important role front to exposure.


Assuntos
Água Potável/química , Exposição Ambiental/análise , Poluição por Petróleo/estatística & dados numéricos , Percepção Social , Poluição da Água/estatística & dados numéricos , Equador , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Humanos , Compostos Orgânicos , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos , Rios , Poluentes Químicos da Água , Poluição da Água/análise , Qualidade da Água
19.
Sci Total Environ ; 693: 133496, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31376752

RESUMO

Nowadays, air pollution has a major impact on the environment and human health. Owen gauges allow the sampling of atmospheric depositions in polluted sites for further characterisation. This paper shows the study of the air particles of an old mining zone in Cartagena-La Unión (South-east of Spain) in order to quantify their potential risk on human health. There were 4 strategic sites monitored: the main mining tailing (Avenque), the urban area (La Unión), an agricultural zone (formerly mining) and a site in the Mediterranean coast. Physico-chemical and mineralogical characterisation was applied to atmospheric fallouts. The granulometry revealed a dust particle size around 15 µm, with the coarsest particles in the urban area and the thinnest at the tailing site. XRD analyses showed the presence of quartz, carbonates, sulphides and sulphates. Observations with SEM-EDX confirmed chemical spectra and allowed us to classify the particles into well-crystallised minerals and heterogeneous dusts. Total metal content determination was carried out by ICP-MS analyses and results showed Zn, Pb, As and Cd fluxes (respectively 2549, 1275, 68 and 7 µg·m-2·d-1) exceeding the limit values set by European legislations in the mining area. The fluxes of Zn, Pb and As also exceed these standards in the urban area whereas the coastal zone only exceeds the thresholds in the case of As. Inhalation health risk (defined by US EPA, 2009) was quantified in the sites using total and bioaccessible metal contents of the dusts. Risk calculations using total metal content considering a residential scenario showed acceptable risk for all sites except for the mining tailing which presented non-acceptable cancer and hazard risk mainly due to the total As and Pb contents. When considering the bioaccessible fraction of As and Pb, the risk diminished to acceptable values, demonstrating the overestimation produced when using total metal contents.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poeira/análise , Monitoramento Ambiental , Humanos , Mineração , Medição de Risco , Espanha
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