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1.
J Agric Food Chem ; 68(5): 1213-1225, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31903748

RESUMO

Organically farmed rice is believed to be healthier, safer, and eco-friendlier than its conventionally farmed counterparts and sells for a premium price in global markets. Deliberate mislabeling of organic rice has become a critical consumer concern in China and elsewhere, and there is an increased risk of buying fraudulent organic rice in the market place. In this study, stable isotopic and multielemental analysis combined with chemometrics was used to differentiate organically farmed rice from green and conventional rice in a 4-year experimental field trial from 2014 to 2017. A total of 108 rice samples and their associated soils were collected during the study from three farming (fertilization) systems to investigate whether there are long-term changes in the rice farming classification accuracy from climate effects. Stable carbon and nitrogen isotopic ratios (i.e., δ13C and δ15N) and 27 elemental contents (e.g., Na, K, Ca, Fe, and Zn) of rice and soil samples were determined and then evaluated using statistical analysis [i.e., one-way analysis of variance, multivariable correlation analysis, and modeling of partial least-squares discriminant analysis]. Although δ15N values can be an effective indicator for organic rice authentication during one crop rotation, both δ13C and δ15N values of rice were easily affected by rice cultivar and interannual soil fertilization and localized agroclimatic variations. These two isotopes were not able to separate organic rice from green and conventional rice accurately. Elemental contents of green and conventional rice (especially K and Ca) were found at higher levels due to the abundant application of synthetic fertilizers (e.g., KNO3, KH2PO4, and CaHPO4), unlike organically farmed rice, which primarily used animal manure and composts. Partial least-squares discriminant analysis modeling combined isotopic and elemental signatures to correctly differentiate organic rice from green and conventional counterparts, with an accuracy up to 100% over the 4-year study. Therefore, this multi-isotope and -element strategy proposes a more rigorous, alternative tool to combat fraudulent mislabeling of organic rice, increasing the trust of organically labeled rice products and supporting the integrity of the organic sector worldwide.


Assuntos
Isótopos de Carbono/análise , Contaminação de Alimentos/análise , Alimentos Orgânicos/análise , Isótopos de Nitrogênio/análise , Oryza/química , Oligoelementos/análise , China , Análise Discriminante , Fertilizantes/análise , Oryza/classificação , Solo/química
2.
J Sci Food Agric ; 100(3): 1294-1300, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31742701

RESUMO

BACKGROUND: Maize (Zea mays L.) is a staple cereal crop and feed crop throughout the world. In this article, a mineral element fingerprinting technique was applied to single out suitable element indicators to determine the geographical origin of maize. A total of 90 fresh maize samples were collected in 2107 from Jilin, Gansu, and Shandong provinces in China. The contents of 25 mineral elements in all maize samples were measured by inductively coupled plasma mass spectrometry (ICP-MS). The composition of mineral elements was analyzed by multivariate statistical analysis, including one-way analysis of variance (one-way ANOVA), principal component analysis (PCA), k-nearest neighbor (KNN) analysis, and stepwise linear discriminant analysis (SLDA). RESULTS: As compared by one-way ANOVA, the contents of 19 mineral elements in maize samples were significantly different among three provinces. Principal component analysis based on these 19 elements could obtain preliminary visual classification groups of maize samples. K-nearest neighbor analysis produced a total correct classification rate of 83.9% on the training set, and 82.2% on the prediction set. The SLDA model, based on eight indicative elements (Na, Cr, Rb, Sr, Mo, Cs, Ba, and Pb) obtained a total correct classification rate of 92.2% with cross-validation. CONCLUSION: The mineral element fingerprinting technique combined with multivariate statistical analysis could be a helpful method to identify the geographical origin of maize. © 2019 Society of Chemical Industry.


Assuntos
Minerais/análise , Oligoelementos/análise , Zea mays/química , China , Análise Discriminante , Geografia , Análise de Componente Principal , Análise Espectral
3.
Crit Rev Anal Chem ; 50(1): 78-89, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30777442

RESUMO

The separation and purification techniques of chelates can improve the accuracy of detecting results of the chelation rate. As a quantitative indicator of metal ion chelates, the chelation rate can not only reflect the completion of chelation but also determine the amount of metal ions in different forms. The determination of chelation rate can help to determine the suitable chelating reaction conditions, make theoretical basis for the fertilizer efficiency, analyze the stability of chelating fertilizers and study the action mechanism of trace elements. In our study, the methods of separation free metal ions from mixture were reviewed first, including gel filtration chromatography, organic solvent precipitation, ion exchange chromatography, membrane separation and high performance liquid chromatography. Then, the qualitative analysis methods of chelates were introduced briefly, including chemical identification, infrared spectroscopy, ultraviolet spectroscopy. A detailed overview of the quantitative determination methods of chelates were also shown, such as ethylenediaminetetraacetic acid titration, chemical titration, atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry, spectrophotometric, chemical modified electrode. In addition, the merits and demerits of chelated rate determination methods of various determination methods were analyzed, and summarized the applicability of various methods, which provided a theoretical basis for optimizing chelating process, characterizing the structure of chelates and analyzing the mechanism of chelating fertilizer. The current methods of measuring chelation rate were also summarized and prospected.


Assuntos
Quelantes/química , Complexos de Coordenação/química , Metais/química , Cromatografia Líquida , Cinética , Espectrometria de Massas , Solventes/química , Espectrofotometria Atômica , Oligoelementos/análise
4.
Chemosphere ; 238: 124528, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31425869

RESUMO

A dendrochemical study of cottonwood trees (Populus deltoides) was conducted across a childhood cancer cluster in eastern Sandusky County (Ohio, USA). The justification for this study was that no satisfactory explanation has yet been put forward, despite extensive local surveys of aerosols, groundwater, and soil. Concentrations of eight trace metals were measured by ICP-MS in microwave-digested 5-year sections of increment cores, collected during 2012 and 2013. To determine whether the onset of the first cancer cases could be connected to an emergence of any of these contaminants, cores spanning the period 1970-2009 were taken from 51 trees of similar age, inside the cluster and in a control area to the west. The abundance of metals in cottonwood tree annual rings served as a proxy for their long-term, low-level accumulation from the same sources whereby exposure of the children may have occurred. A spatial analysis of cumulative metal burdens (lifetime accumulation in the tree) was performed to search for significant 'hotspots', employing a scan statistic with a mask of variable radius and center. For Cd, Cr, and Ni, circular hotspots were found that nearly coincide with the cancer cluster and are similar in size. No hotspots were found for Co, Cu, and Pb, while As and V were largely below method detection limits. Whereas our results do not implicate exposure to metals as a causative factor, we conclude that, after 1970, cottonwood trees have accumulated more Cd, Cr, and Ni, inside the childhood cancer cluster than elsewhere in Sandusky County.


Assuntos
Monitoramento Ambiental , Neoplasias/epidemiologia , Populus/química , Oligoelementos/análise , Criança , Humanos , Ohio/epidemiologia , Solo/química , Análise Espacial , Inquéritos e Questionários , Árvores/química
5.
Chemosphere ; 239: 124718, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31514008

RESUMO

Agaricus bisporus is the most commonly cultivated and consumed mushroom species. The aim of this study was to compare the profile of macro- and trace elements in A. bisporus fruit bodies produced commercially in 19 countries in 2018 and distributed worldwide (32 analyzed objects). Trace elements with unknown biological roles were also determined. The content of 36 elements (of 70 taken into account) revealed significant differences among the analyzed objects. Contents of Ca, K, Mg, Na and S varied in wide ranges of 425-2430, 12740-40940, 610-3240, 98-430 and 1030-2650 mg kg-1 dw, respectively. The fruit bodies were characterized by a generally similar content of trace elements with some clear exceptions. Rankings of the objects according to the decreased amount of macroelements, trace elements and all elements jointly, show that mushrooms are significantly diverse as regards the content of particular elements of the mentioned group. The analyzed fruit bodies displayed a relatively high content of Ca, Mo and Se, and a high K/Na ratio. Regardless of origin, A. bisporus did not constitute a source of significant levels of Al, Cd or rare earth elements. An increased level of As and Pb in mushrooms from several producers indicates a need for additional measures to reduce potential dietary exposures to these toxicants.


Assuntos
Agaricus/química , Inquéritos e Questionários , Oligoelementos/análise , Arsênico/análise , Saúde Global , Chumbo/análise
6.
Chemosphere ; 239: 124809, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31527008

RESUMO

Honey is a highly nutritious natural product widely produced and consumed by people in Shirak and Syunik regions of Armenia. Unlike Shirak, Syunik is under the impact of mining industry. Since the environmental pollution can adversely impact the safety of honey and entail a probable risk to human health, it is important to evaluate the presence of potentially toxic trace elements in honey samples from both regions and draw comparisons. This study assesses the dietary exposure to trace elements and persistent organic pollutants through the intake of honey for the first time among people in Shirak and Syunik regions. 24-hour dietary recall method was used to investigate the consumption of honey. The presence of seven trace elements (Pb, Cd, As, Hg, Cu, Zn, and Ni) and persistent organic pollutants (hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT) and its metabolites) were determined in honey samples using atomic absorption spectrometry and gas chromatography-mass spectrometry, respectively. In several samples, the concentrations of Cu were above the maximum allowable level. Non-carcinogenic risk values did not exceed the acceptable level, while carcinogenic risk values for Ni and As exceeded the risk level of 10-6 in both regions. Moreover, among the persistent organic pollutants, only the concentration of DDT in honey from Shirak was above the European Union maximum residue level.


Assuntos
Carcinógenos/análise , DDT/análise , Exposição Dietética/análise , Mel/análise , Medição de Risco/métodos , Oligoelementos/análise , Armênia , Poluentes Ambientais/análise , Poluição Ambiental/análise , Mel/toxicidade , Humanos , Metais Pesados/análise , Mineração , Espectrofotometria
7.
Chemosphere ; 239: 124770, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726525

RESUMO

Over twenty thousand persons rely on water from Atuwara River for drinking and other domestic purposes, hence the need to ascertain the human health risk inherent in such practice. Seventy-two water samples were collected from River Atuwara during the dry and wet seasons of 2018, and the concentration of heavy metals (Pb, As, Ni, Cr, Zn, Cu, and Cd) were measured using ICP-OES. A newly developed human health risk assessment method, HHRISK code was used to estimate the health risks associated with consumption of water from Atuwara River. Results obtained revealed that the concentration of heavy metals in the river was as follows: Cd < Ni < Pb < Cr < Cu < As < Zn in the wet season and Cd < Pb < Ni < Cu < Cr < As < Zn during the dry season. Principal component analysis suggested that industrial effluents, agricultural activities and base-rock interaction are responsible for pollution of Atuwara River. The cumulative hazard index (HIcum) obtained was 678.0 ±â€¯36.8 (for adult) and 1392.0 ±â€¯132 (for child) for non-carcinogenic risks. A cumulative carcinogenic risk (CRcum) of 1.01E-1±5.26E-3 and 4.96E-2±5.05E-3 was obtained for adult and children respectively, suggesting that up to 1 in 10 adults and 1 in 20 children may suffer from cancer over their lifetime as a result of consumption and exposure to water from River Atuwara. These results highlight the fact that unavailability of safe drinking water in many parts of the world remains a real and persistent risk which must be tackled.


Assuntos
Água Potável/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Adulto , Agricultura , Criança , Humanos , Nigéria , Análise de Componente Principal , Medição de Risco , Rios , Estações do Ano , Qualidade da Água
8.
Sci Total Environ ; 699: 134329, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31522040

RESUMO

The marine environment is subjected to ever-increasing levels of contamination, especially along the coastal areas with urban and industrial activities. Consequently, monitoring campaigns on large scales should be conducted on a regular basis for a better management of marine ecosystems. This study tested the capacity of the green alga Ulva lactuca to act as a bioindicator of trace elements along the coasts of Sicily (Italy). The concentrations of the metals Cd, Cr, Cu, Ni, Pb and Zn were analyzed in samples of water, sediments and U. lactuca thalli, which were collected in ten different sites at diverse levels of human impact. The results showed that U. lactuca can accumulate essential and non-essential elements at similar concentrations. The analysis of trace elements showed also that the metal content in U. lactuca is significantly correlated with the levels of trace elements in water and sediments. U. lactuca fits numerous features that make it one of the best bioindicators of marine pollution, also thanks to its worldwide distribution and capacity to accumulate trace elements under toxic conditions. The use of U. lactuca should be encouraged to set up large-scale monitoring programs, especially in highly impacted seas like the Mediterranean where U. lactuca is widespread.


Assuntos
Monitoramento Ambiental , Oligoelementos/análise , Ulva , Poluentes Químicos da Água/análise , Biomarcadores Ambientais , Sicília
9.
Chemosphere ; 240: 124938, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574444

RESUMO

Clearwater Mesa (James Ross Island, northeast Antarctic Peninsula) provides a unique opportunity to study solute dynamics and geochemical weathering in the pristine lacustrine systems of a high latitude environment. In order to determine major controls on the solute composition of these habitats, a geochemical survey was conducted on 35 lakes. Differences between lakes were observed based on measured physico-chemical parameters, revealing neutral to alkaline waters with total dissolved solids (TDS) < 2500 mg L-1. Katerina and Trinidad-Tatana systems showed an increase in their respective TDS, total organic carbon values, and finner sediments from external to internal lakes, indicating an accumulation of solutes due to weathering. Norma and Florencia systems exhibited the most diluted and circumneutral waters, likely from the influence of glacier and snow melt. Finally, isolated lakes presented large variability in TDS values, indicating weathering and meltwater contributions at different proportions. Trace metal abundances revealed a volcanic mineral weathering source, except for Pb and Zn, which could potentially indicate atmospheric inputs. Geochemical modelling was also conducted on a subset of connected lakes to gain greater insight into processes determining solute composition, resulting in the weathering of salts, carbonates and silicates with the corresponding generation of clays. We found CO2 consumption accounted for 20-30% of the total species involved in weathering reactions. These observations allow insights into naturally occurring geochemical processes in a pristine environment, while also providing baseline data for future research assessing the impacts of anthropogenic pollution and the effects of climate change.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Lagos/química , Minerais/análise , Compostos Orgânicos/análise , Oligoelementos/análise , Regiões Antárticas , Carbonatos/análise , Mudança Climática , Ecossistema , Camada de Gelo/química , Chumbo/análise , Trinidad e Tobago , Tempo (Meteorologia) , Zinco/análise
10.
J Sci Food Agric ; 100(2): 885-890, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31483055

RESUMO

BACKGROUND: The research focused on the evaluation of the impact of cover cropping on trace metals (Fe, Mn, Cu, Zn, Pb, Co and Cd) and nutrients in vineyard soils and Vitis vinifera L. For this purpose, two types of cover crops (Lolium perenne L. and Medicago sativa L.) and their mixture were planted between vine rows of Muscat white in the vineyard in South Crimea. Trace elements, nutrients and other parameters were analyzed in the soil layers, leaves and grapevines of control and cover cropped plots. RESULTS: The effect of cover cropping was dependent on applied plant species. Ryegrass (L. perenne L.) seems to compete with V. vinifera L. for nutrients - these were lower in the soil and vines of the treated plot. In parallel, lead (Pb) bioconcentration in grapevines was reduced. In contrast, under lucerne (M. sativa L.), nitrogen in the soil and vines, and trace metal bioconcentration (Fe, Pb and Co) were higher. CONCLUSIONS: Our results indicate that cover cropping can influence the chemical composition of soil and vines. This should be considered when selecting cover crops. © 2019 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Lolium/crescimento & desenvolvimento , Medicago/crescimento & desenvolvimento , Oligoelementos/análise , Vitis/química , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Lolium/metabolismo , Medicago/metabolismo , Nutrientes/análise , Nutrientes/metabolismo , Solo/química , Especificidade da Espécie , Oligoelementos/metabolismo , Vitis/crescimento & desenvolvimento , Vitis/metabolismo
11.
J Sci Food Agric ; 100(2): 623-633, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31591726

RESUMO

BACKGROUND: The need to increase marketable tomato yields and decrease losses due to sunburn and disease during the summer motivates farmers to adopt additional cultural practices such as shading and grafting. To investigate complex interactions among grafting, shading, and tomato cultivar, grafted and ungrafted tomatoes (cv. 'Optima' F1 and cv. 'Big Beef' F1 ) were grown in the soil under net-house cover, using pearl and red nets, and in unshaded conditions (open fields). Tomato fruit at the red stage of maturity were used for the analysis of quality traits, and total and marketable yields were recorded during the whole production season. RESULTS: Grafting and shading in tomato production might be considered as cultivation practices to increase the marketable tomato yield. A decrease in sugar content increased the uptake of some micro elements (Fe and Zn) and macro elements (Ca). In some cases, firmer and less elastic skin may be expected due to grafting. Shading with pearl net might result in fruit with lower firmness and higher total, and particularly malic, acid content. CONCLUSION: Shading with colored nets and grafting provide alternative strategies for achieving higher fruit yields and avoiding or reducing a decrease in tomato quality caused by environmental stresses such as excessive radiation and temperature in the summer cropping season. © 2019 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Frutas/química , Lycopersicon esculentum/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Lycopersicon esculentum/química , Melhoramento Vegetal/métodos , Estações do Ano , Açúcares/análise , Temperatura Ambiente , Oligoelementos/análise
12.
Chemosphere ; 238: 124569, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31442777

RESUMO

Point pollution sources may differently impact lakes littoral, possibly leading to local ecological risks. The concomitant chemical analysis of littoral-benthic organisms and sediment can provide insights into the bioavailability and thus the ecological risk of contaminants. In this study, the autochthonous Corbicula fluminea was used to assess the sources and transfer of six trace metals (TMs) and fourteen Polycyclic Aromatic Hydrocarbons (PAHs) to the littoral-benthic biota of a large lake. The contaminant concentrations spatially varied with a value scale from 1 to 280 000 times along the lake littoral in both the sediment and clams. Multiple linear regressions were performed to explain the spatial variability of Corbicula fluminea contamination by considering both watershed and in-lake sources. The concentration of the sum of PAHs in clams was significantly correlated with sediment contamination, suggesting that PAHs contamination of the benthic biota mainly occur from the sediment. Most of the internal TM concentrations of clams were significantly correlated with stormwater drainage areas in the lake watershed, highlighting the importance of stormwater runoffs in the littoral biota contamination. The transfer of TMs and PAHs was assessed through the bioconcentration factor defined as the ratio of internal and sediment concentrations. As, Cd, Cu, Zn and light molecular weight PAHs were more bioconcentrated in C. fluminea than Pb, Sn and heavy molecular weight PAHs, suggesting differences in their bioavailability. This study underlines the relevance of using autochthonous organisms as bioindicators of lake littoral biota contamination concomitantly with sediment matrices, and illustrates the challenge of tracking pollution sources in lakes.


Assuntos
Corbicula/química , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Biota , Biomarcadores Ambientais , Lagos/química , Metais Pesados/análise , Alimentos Marinhos/análise
13.
Environ Monit Assess ; 191(12): 780, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31786680

RESUMO

Mangrove sediments are strong modulators of organic matter (OM) content and pollutant dynamics, acting both as sinks and sources of these components. This study aimed to assess temporal dynamics of OM within temperate mangrove sediments and their ability to sequester pollutants. Specifically, levels of trace metals (Fe, Cu, Zn, Pb, Cd) and a metalloid (As) were examined within mangrove and mudflat sediments located in a high-energy environment in Mangawhai Harbour Estuary, northern New Zealand. Sediment cores were collected from a mangrove stand and adjacent mudflats at three sediment depths during different months over a year. Variations in OM and elements were compared to rainfall and temperature patterns observed during the sampling period. All element concentrations, except for those of As, were significantly higher in mangrove compared to mudflat sediments during the entire sampling period. This is consistent with the well-reported ability of mangroves to trap suspended particles and OM. In addition, we observed a decreasing trend in trace metal concentrations with increasing sediment depth within mangrove habitat, which correlated well with decreasing OM content. Our results also suggested that most elements had different, but significant, temporal variations throughout the year, especially in mangrove sediments. Overall, the concentrations of Cu, Zn, Pb, Cd, and As in mangrove sediments increased during summer, whereas maximum levels of Fe and OM were observed in winter. This temporal pattern was determined to be related to OM and redox cycling as a result of changes in effluent input rates and physical/chemical environments during different seasons.


Assuntos
Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Metaloides , Metais Pesados , Oligoelementos , Sedimentos Geológicos/química , Metaloides/análise , Metais Pesados/análise , Nova Zelândia , Estações do Ano , Oligoelementos/análise , Poluentes Químicos da Água/análise
14.
Environ Monit Assess ; 191(12): 713, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676983

RESUMO

Environmental pollution has received considerable attention over the last 50 years. Recently, there has been an increasing interest in pollution of the Nile Delta, Egypt, which is one of the longest settled deltaic systems in the world. Pollution in the delta is increasingly recognized as a serious health concern that requires proper management of ecosystems. Therefore, this project aimed to study the distribution and assess the risk associated with selected trace elements (TEs) in different soils (i.e., marine, fluvial, and lacustrine parent materials) in the northern Nile Delta. Mehlich-3 extraction was used to determine the availability of antimony, vanadium, strontium, and molybdenum in agro-ecosystems in this area and their spatial distributions were investigated. Five indices were used to assess ecological risk. Results showed that TEs were higher in the southern part of the study area because it is affected by multiple pollution sources. The available concentrations of TEs were Sr < V < Sb < Mo. The bioavailability of Sr was highest among the studied TEs. The studied indices suggested the study area was moderately polluted by Sr and Sb. Furthermore, the results showed that marine soils had higher TE levels then lacustrine and fluvial soils. The ecological risk assessment indicated that V and Mo were of natural origin, while Sr and Sb were anthropogenically linked. Therefore, the situation calls for planning to reduce pollution sources, especially in the protected north Nile Delta, so these productive soils do not threaten human and ecological health.


Assuntos
Monitoramento Ambiental , Poluentes do Solo/análise , Solo/química , Oligoelementos/análise , Antimônio , Disponibilidade Biológica , Ecossistema , Egito , Poluição Ambiental/análise , Poluição Ambiental/estatística & dados numéricos , Humanos , Metais Pesados/análise , Molibdênio , Medição de Risco
15.
Environ Monit Assess ; 191(11): 698, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667658

RESUMO

Sita, a small tropical river originating in the Western Ghats, southwestern India, was chosen for this study to understand the spatial and temporal variability of dissolved trace elements and major ions. Sampling was done in monsoon, post-monsoon and pre-monsoon seasons across the river catchment. Dissolved elements like Zn, Ni, Cu and Co showed high concentrations during monsoon which could be because of the intense chemical weathering of silicate rocks in the catchment, surface runoff and wet atmospheric deposition. In the remaining seasons, the river is fed by the groundwater and anthropogenic effluents which is contributing to higher concentrations of dissolved Pb, Fe and Cd. The results are analysed using factor analysis (SPSS 12), which helped to delineate the sources of metal assemblages. Factor 1 is dominated by major ions (Na, K, Cl, Mg, Ca), which could be naturally sourced from atmospheric deposition and weathering of rocks. Factor 2 is dominated by trace metals (Cd, Pb, Co) and sulphates (SO4) which may have anthropogenic sources such as the discharge of domestic and industrial effluents and agricultural effluents.


Assuntos
Monitoramento Ambiental , Metais/análise , Poluentes Químicos da Água/análise , Água Subterrânea , Índia , Íons/análise , Rios/química , Estações do Ano , Oligoelementos/análise , Tempo (Meteorologia)
16.
Environ Monit Assess ; 191(12): 753, 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31734747

RESUMO

Pollution and health risk assessment models were used to study the effects of effluents discharged into the Inyishi River, Ikeduru LGA, Imo State, Nigeria. The study aims at investigating the environmental health effects of wastewater effluent discharge from the aluminum extrusion company on the Inyishi River. Samples were collected from both the aluminum extrusion company and Inyishi River and analyzed for physicochemical and trace metal parameters. Models adopted for assessment include transfer factor (TF), contamination factor (Cf), pollution load index (PLI), ecological risk factor (Er), water quality index (WQI), hazard quotient (HQ), and hazard index (HI). The results of the study revealed that pH and TH were within the Nigerian Standard for Drinking Water Quality (NSDWQ) and World Health Organization (WHO) standards. EC values at 2235 ± 0.001 and 105 ± 0.03 µS/cm for S3 and S4 respectively were higher than the permissible standards, while the values of EC at 24.04 ± 0.03, 5.26 ± 0.005, and 0.05 ± 0.01 µS/cm respectively for S1, S2, and SR are within the WHO standard. Very high concentration of SO42- was recorded at S3, while low concentration was measured at S2. Mean values of heavy metal ions studied were within NSDWQ and WHO standards for safe drinking water except for Al, Zn, Cd, Fe, and Mn, with the mean values of metal concentrations observed in the order Al > Fe > Zn > Mn > Cd > Cr. Positive linear correlation based on heavy metal contamination was observed for samples S1 and S2 with SR. High TF values were observed in decreasing order Mn > Cd > Cr > Fe > Zn. Similarly, very high CF was observed for Cd and Al while the PLI was generally high for all the samples. Low Er values were observed for all metals except for Cd, with the mean value of Er observed in the decreasing order Cd ˃ Mn ˃ Zn ˃ Cr. The river water sample generally revealed high WQI and was thus categorized as poor quality. HQ and HI values were below unity (< 1), but might pose health risk to children in cases of prolonged dermal adsorption. In conclusion, the quality of the Inyishi River has been negatively impacted by the wastewater effluent from the aluminum extrusion company. Proper treatment of the river water is therefore recommended before use for domestic purposes as prolonged usage of the untreated water might likely pose serious environmental health risks.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Rios/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Qualidade da Água , Criança , Ecologia , Humanos , Nigéria , Medição de Risco , Oligoelementos/análise , Poluição Química da Água
17.
Ecotoxicol Environ Saf ; 186: 109628, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31614301

RESUMO

The water quality in drinking water source area is essential for human health. Due to rapid urbanization and industrialization, the pollutants, especially trace elements, are continuously discharged into aquatic environment and pose a risk to human health. An extensive investigation was carried out in drinking water source area in highly urbanized Tianjin of China. Long-term monitoring data of the water body was collected on conventional physical and chemical parameters (pH, ions, TOC etc.) and metallic elements (Hg, As Cd, Pb, Co, U etc.) from 2005 to 2017. Our results showed that CaMg-Cl-SO4 and CaMg-HCO3 were the two prominent hydrochemical materials, implying that the pollution of aquatic system was mainly caused by anthropogenic activities and mineral dissolution within terms of drinking water guidelines (national and international standards), the concentrations of arsenic (As) and iron (Fe) were beyond the quality standards. Multivariate statistical approaches were applied to assess the origins of the elements. The results showed that human activities, as well as endogenous release, contributed significantly to appearance of trace elements. A transformation from low-trophic state to high-trophic state was in progress from 2005 to 2017 in Yuqiao reservoir, and most of the water was not heavily polluted by trace elements. The health risk assessment suggested that As had the potential to cause carcinogenic harm to the local residents, with daily dietary ingestion as the most predominant pathway.


Assuntos
Água Potável/normas , Exposição Ambiental/análise , Monitoramento Ambiental , Água Doce/química , Água Subterrânea/química , Poluentes Químicos da Água/análise , China , Água Potável/química , Humanos , Medição de Risco , Oligoelementos/análise , Urbanização
18.
Environ Sci Pollut Res Int ; 26(33): 34401-34411, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31637617

RESUMO

The peri-urban soil is exposed to pollutants because of its proximity to the city, which may influence the quality of agricultural products. In this study, the occurrence of 16 trace elements (TEs), 16 polycyclic aromatic hydrocarbons (PAHs), and 33 contaminants of emerging concern (CECs) was analyzed in two soil sites of the peri-urban area of Barcelona (Spain) (S2 and S3) and a pristine site (S1). Levels of Pb (S2 164 and S3 150 mg kg-1) are around 2.5 times higher than the guideline values. Values for Cu (178 mg kg-1) in S2 are 1.8-fold higher, whereas for Zn, levels are slightly above the threshold in S2 (208 mg kg-1) and S3 (217 mg kg-1). The total concentrations of PAHs are significantly below the limits: 24 ng g-1 dw (S1), 38 ng g-1 dw (S2), 49 ng g-1 dw (S3), whereas only some CECs are detected with low concentrations. We also developed a simple and rapid method to assess soil pollution. Here, we use two plant growth indexes (seed germination rate and root elongation at the initial stage) of three seeds (lettuce, tomato, and cauliflower) to assess soil chemical contamination on agriculture. In the peri-urban soil, the concentration of Pb was 2.5 times higher than the guideline values, whereas for Cu and Zn, values were slightly above their limits, while only few PAHs and CECs were detected. Results for principal component analysis suggest that root elongation is a more sensitive measurement endpoint than germination rate, especially for lettuce. The germination rate of tomato relied on the nitrate in the soil and decreased sharply in the site with pollution of Cu and As. Under the specific conditions of this study, cauliflower should not be recommended to assess environmental pollution due to its low sensitivity to pollutants. In conclusion, this is a low-cost, simple, and rapid method for evaluating the effects of chemical pollution of agriculture soils on seed growth.


Assuntos
Monitoramento Ambiental , Poluentes do Solo/toxicidade , Agricultura , Cidades , Poluição Ambiental/análise , Germinação/efeitos dos fármacos , Alface , Hidrocarbonetos Policíclicos Aromáticos/análise , Sementes/química , Solo/química , Poluentes do Solo/análise , Espanha , Oligoelementos/análise
19.
Environ Monit Assess ; 191(11): 666, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650329

RESUMO

The presence of several trace elements, heavy metals, and antimony in polyethylene terephthalate-bottled local raw cow milk samples of Igdir region in Turkey was investigated. The milk samples were analyzed by inductively coupled plasma mass spectrometry after microwave-assisted digestion. Milk samples were categorized into three groups according to the element level intensity in the sample. While 70% of samples showed 2.5 times the maximum Turkish and European permissible level of lead, the lowest lead-contaminated sample exhibited 1.25 times this level. All the examined samples exceeded the maximum permissible limit administrated for arsenic and 35% of samples exhibited 5 times this limit. Results showed 40% of samples contain an antimony level higher than the Turkish maximum allowable concentration. The high antimony content of raw milk samples may be related to the release of antimony from the PET (polyethylene terephthalate) bottles. This study showed high contamination levels of the most toxic trace elements, i.e., lead and arsenic in milk and possible antimony contamination from PET bottles which may cause many health hazards for the consumers.


Assuntos
Antimônio/análise , Contaminação de Alimentos/análise , Metais Pesados/análise , Leite/química , Oligoelementos/análise , Animais , Arsênico/análise , Bovinos , Monitoramento Ambiental , Feminino , Inocuidade dos Alimentos , Polietilenotereftalatos , Espectrofotometria Atômica , Turquia
20.
Environ Monit Assess ; 191(11): 686, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664537

RESUMO

Due to water scarcity, the groundwater will represent an essential source of water in many communities worldwide. This study was carried out to investigate the main hydrogeochemical characteristic of trace elements composition, their sources, and its vulnerability in groundwater to the human population. Fifteen groundwater samples were collected from boreholes and hand dug wells from the South Eastern Desert, Egypt, and analyzed for Al, As, B, Fe, Mn, Cd, Co, Cr, Cu, Hg, Ni, Pb, Rb, Sb, Sr, Th, U, V, and Zn using inductively coupled plasma mass spectrometry. Multivariate analyses were applied to identify the distribution and potential source of trace elements. The groundwater is tapped from the Miocene and the fractured basement rock aquifers. The mean concentrations of trace elements exceed the guideline values of all organizations, except in some wells for Zn, Cu, and Co. Cationic trace elements declined in the order of Mn > Fe > Zn > Al > V > Ni > Rb > Sr > U > Cu > Cr > Co > Cd > Pb > Th > Sb > Hg. Oxyanions As (mean 15.48 mg/L) and B (mean 1.24 mg/L) showed very high concentrations and higher than the average WHO concentrations in water suggesting potential adverse toxicity to all aquatic organisms. Five factor analyses indicated that different geochemical contributions are involved in the chemical characteristics of groundwater in the study area. Water-rock interaction and dissolution processes in bed rocks from different coastal Miocene deposits, meta-volcanics, basic-ultrabasic rocks, granitic and meta-sediments, seawater intrusion, residential wastes, and mining activities, in addition to the pH/Eh conditions, adsorption, and surface complexation during the chemical weathering are the main factors influence the trace elements distribution in groundwater. Results from this study for the six different groundwater aquifers are a unique insight into the sources and mobility of the observed trace elements in the groundwater and can be used in the assessment of contamination for drinking water wells. The association of trace elements from different aquifers might be useful in tracers studies of water-rock interaction. Due to the enrichment of trace elements in nearshore and crystalline groundwater aquifers in the study area and in similar areas worldwide, treatment technologies, and sustainable water management processes should be applied to prevent severe risks to the communities.


Assuntos
Monitoramento Ambiental , Oligoelementos/análise , Poluentes Químicos da Água/análise , Adsorção , Egito , Água Subterrânea/química , Humanos , Mineração , Análise Multivariada , Poços de Água
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