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1.
Environ Monit Assess ; 196(8): 687, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958826

RESUMO

Fluvial sediment analysis and water quality assessment are useful to identify anthropic and natural sources of pollution in rivers. Currently, there is a lack of information about water quality in the Pixquiac basin (Veracruz state, Mexico), and this scarcity of data prevents authorities to take adequate measures to protect water resources. The basin is a crucial territory for Xalapa, the capital city of Veracruz state, as it gets 39% of its drinkable water from it. This research analyzed 10 physicochemical parameters and 12 metal concentrations in various rivers and sources during two seasons. Dissolved metals presented average concentrations (µg/L): Al (456.25) > Fe (199.4) > Mn (16.86) > Ba (13.8) > Zn (7.6) > Cu (1.03) > Pb (0.27) > As (0.12) > Ni (0.118) (Cd, Cr and Hg undetectable). Metals in sediment recorded average concentrations (ppm): Fe (38575) > Al (38425) > Mn (460) > Ba (206.2) > Zn (65.1) > Cr (29.8) > Ni (20.9) > Cu (16.4) > Pb (4.8) > As (2.1) (Cd and Hg undetectable). During the rainy season, Water Quality Index (WAWQI) classified stations P17 and P18's water as "unsuitable for drinking" with values of 110.4 and 117.6. Enrichment factor (EF) recorded a "moderate enrichment" of Pb in sediment in P24. Pollution was mainly explained by wastewater discharges in rivers but also because of erosion and rainfall events. Statistical analysis presented strong relationships between trace and major metals which could explain a common natural origin for metals in water and sediment: rock lixiviation.


Assuntos
Água Potável , Monitoramento Ambiental , Sedimentos Geológicos , Poluentes Químicos da Água , Qualidade da Água , Abastecimento de Água , México , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Água Potável/química , Rios/química , Metais Pesados/análise , Metais/análise
2.
Sci Rep ; 14(1): 9681, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678097

RESUMO

The indiscriminate disposal of spent engine oils and other hazardous waste at auto mechanic workshops clusters in Nsukka, Enugu State, Nigeria is an environmental concern. This study examines the concentration of heavy metals in the soil inside the workshop cluster and in the unpolluted soil outside the workshop cluster at approximately 100 m. Ten sampling points were randomly selected from within the cluster and another ten from outside the cluster. Using a hand-held Global Positioning System, the coordinates of the selected points were established and used to create a digital map. Soil samples at depths of 0-30 cm and 30-60 cm, were analyzed for Cu, Fe, Zn, Pb, As and Cd using Spectrophotometer. Moisture content determination and particle size analysis were also done on the samples. Spatial variability of heavy metals concentrations of the studied site was also mapped with ArcGIS 10.2.2 using interpolation methods. Results showed that the soil ranged from sandy loam to sandy clay loam. Cadmium and Zinc had the lowest and highest concentration, respectively, in the studied area. Comparing the concentrations of heavy metals in soils within and outside the auto mechanic cluster revealed notable differences across various depths (0-30 cm and 30-60 cm). The analysis results for soil samples within the cluster exhibited concentration levels (mg/kg) ranging from 0.716-0.751 (Cu), 2.981-3.327 (Fe), 23.464-30.113 (Zn), 1.115-1.21 (Pb), 2.6-2.912 (As), and 0.133-0.365 (Cd) demonstrating a variation pattern in the order of Zn > Fe > As > Pb > Cu > Cd. Conversely, for soil samples outside the cluster, concentration levels (mg/kg) ranged from 0.611-0.618 (Cu), 2.233-2.516 (Fe), 12.841-15.736 (Zn), 0.887-0.903 (Pb), 1.669-1.911 (As), and 0.091-0.091 (Cd). To assess the disparity in heavy metal concentration levels between samples collected within and outside the clusters, ANOVA test was performed. The test showed significant difference in heavy metal concentrations between samples within and outside the auto mechanic cluster (p < 0.05), implying auto mechanic activities significantly impact heavy metal levels within the cluster compared to outside areas. The assessment of soil pollution utilized indices including the Geo-accumulation Index (Igeo), Contamination factor (Cf), and anthropogenic metal concentration (QoC). Zinc, Cadmium, and Arsenic showed the highest contamination factors, indicating significant soil contamination likely due to anthropogenic activities. The concentrations of the metals analyzed were within WHO permissible limits while the metals concentrations were also observed to decrease as depth was increased. Using ArcGIS 10.2.2, spatial maps showing heavy metal distribution were developed, with the Kriging method proving superior. This study suggests that heavy metal levels in the soil at the area be monitored on a regular basis.

3.
J Trace Elem Med Biol ; 83: 127412, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38394967

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is a multifactorial disease whose prevalence is increasing worldwide. CKD affects 700 million to 1 billion people worldwide, with a prevalence of 9.1% to 13.4%. In Iran, the reported prevalence of CKD is 15.14%, even higher than the global prevalence. Some studies introduced heavy metals as possible risk factors of CKD. We conducted the first study in Iran to examine the relationship between 10 selected urinary heavy metals and CKD in the Hovayzeh cohort study population. METHODS: In this cross-sectional study, urine samples were collected from two groups of ca ses (suffering from CKD) and controls (without CKD) with equal size (47 people each). Analysis of the 10 sellected heavy metals in the samples was conducted using inductively coupled plasma emission spectroscopy. Basic Information was obtained from the Howayizeh Cohort Study Center. The data was analyzed using SPSS-26 and Excel-2016 software. RESULTS: There were no significant differences between urinary heavy metal concentrations of case and control groups (P < 0.05). While, the concentration of As, Cr, Cu, Mn, and Ni exceeded the reference limits of Germany, Canada, England, and Belgium. Se and Cd also surpassed the reference limits of England. After adjusting for confounding variables for each µg/l increase in urinary Cd, Ni, Pb, and Se the OR of CKD increased by 20.2%, 4.8%, 3.1%, and 2.6%, respectively. Although, these relationships were not statistically significant. In addition, two groups of heavy metals had a positive and significant correlation: (1) Se, Zn, As, Cu, and Cr; (2) Pb, Cd, and As; and (3) Cd and Ni. CONCLUSION: we found no significant relationship between urinary heavy metal and CKD. However, there was significant positive correlation in some of urinary heavy metals may indicate their shared resources. Furthermore, the concentration of most heavy metals in the urine of the participants was higher than the reference limits of these metals in the urine of healthy people from other countries. Thus, the elevated levels of these metals could still pose a risk to human health. Therefore, it is necessary to conduct prospective studies with a larger sample size in this area.


Assuntos
Metais Pesados , Insuficiência Renal Crônica , Humanos , Estudos Transversais , Cádmio/análise , Estudos de Coortes , Estudos Prospectivos , Irã (Geográfico)/epidemiologia , Chumbo/análise , Metais Pesados/análise , Monitoramento Ambiental/métodos , Insuficiência Renal Crônica/epidemiologia
4.
Environ Sci Pollut Res Int ; 31(12): 17546-17564, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36626057

RESUMO

Population expansion and improving living standards, particularly in developed nations, have led to an increase in the usage of domestic electrical equipment, worldwide energy consumption, and CO2 emissions per capita. To limit the usage of non-reusable components and the amount of garbage that must be transferred at the end of a product's life cycle, longer-lasting electrical domestic appliances are a pillar of the circular economy. In recent years, the complexity of printed circuit boards (PCBs) used in the manufacture of modern electrical devices has increased, leading to an increase in device failures. This study focuses on the maintenance and recycling of domestic electrical appliance components and printed circuit boards. The proposed methodology for PCB repair is defined as a sequential quadratic programming (SQP) problem implemented in MATLAB environment and successfully tested to a variety of domestic appliances such as refrigerator, dishwasher and washing machine. The possibility of recycling metal parts of electronic components, which were replaced after PCBs' repair was also studied. Metals' percentage concentration of PCB electronic components for three customer's budgets considering metals and valuable metals recovery as given from the corresponding average metal recovery and calculated from different recycling procedures presented in the literature. The results of the proposed procedure in terms of valuable metals gave 38.4078 ppm of silver. We also compared the suggested procedure with other works in terms of environmental perspective considering four measures, namely the gross energy requirement (GER), the global warming potential (GWP), the acidification potential (AP), and the solid waste burden (SWB). In terms of economic perspective and considering the existence of silver (Ag) in the electronic components, the recommended method gave comparable amount of money. Finally, a comparison of different recycling works from a technical viewpoint is also conducted. Moreover, a reparability index of domestic electrical appliances is introduced to further quantify the results of the proposed algorithm.


Assuntos
Resíduo Eletrônico , Prata , Resíduo Eletrônico/análise , Reciclagem/métodos , Eletrônica , Algoritmos
5.
Mar Pollut Bull ; 197: 115761, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37952375

RESUMO

This study assessed heavy metal levels (lead (Pb), cadmium (Cd), total arsenic (tAs), arsenite (As (III)), arsenate (As (V)), monomethyl arsenic acid (MMA), dimethylarsinic acid (DMA), total mercury (tHg), and methylmercury (MeHg)) in six organs (total portion, head, body, shell, muscle, and intestine) of 11 shrimp species distributed in Korea. Shrimp exhibited significant variability in heavy metal accumulation, with Alaskan pink and dried shrimp (Lesser glass, Southern rough, and Chinese ditch prawn) showing the highest metal concentrations. Notably, the intestine having the highest overall metal content, while Cd was most prominent in the head, tHg was highest in the muscle. The Hazard Quotient values of 11 shrimp species in South Korea were below the European Food Safety Authority's allowable limits for heavy metals. This study illuminates the heavy metal profiles of distributed shrimp in Korea and emphasizes the ongoing need for monitoring heavy metals on seafood to ensure consumer safety.


Assuntos
Mercúrio , Metais Pesados , Animais , Humanos , Cádmio/análise , Especificidade de Órgãos , Contaminação de Alimentos/análise , Metais Pesados/análise , Alimentos Marinhos/análise , Mercúrio/análise , Crustáceos , Medição de Risco , Monitoramento Ambiental
6.
Molecules ; 28(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37570636

RESUMO

In recent decades, new alternative therapies using drugs containing active ingredients of natural origin have been a hot topic for medical research. Based on the confirmed therapeutic potential of the Vinca minor plant, considered in the specialized literature to be of pharmaceutical interest, the purpose of this study is to determine the chemical and mineral composition of the Vinca minor plant grown in the Dobrogea area, with a view to its use in the formulation of dermal preparations. For this purpose, plant materials were collected from the mentioned area and hydroalcoholic macerates of different concentrations were obtained: 40%, 70% and 96% from leaves (F40, F70, F96) and stems (T40, T70, T96) of Vinca minor plant to determine the optimal extraction solvent. The hydroalcoholic macerates were analyzed via the HPLC method for the identification and quantification of the main bioactive compounds, and two methods were used to evaluate their antioxidant properties: the DPPH radical scavenging test and the photochemiluminescence method. HPLC analysis showed the presence of four indole alkaloids: vincamine, 1,2-dehydroaspidospermidine, vincaminoreine and eburnamonine. Vincamine was the alkaloid found in the highest concentration in Vinca leaves (2.459 ± 0.035 mg/100 g d.w.). The antioxidant activity of Vinca minor hydroalcoholic macerates showed values between 737.626-1123.500 mg GAE/100 g d.w (DPPH test) and 77.439-187.817 mg TE/100 g d.w (photochemiluminescence method). The concentrations of toxic metals Cd, Cu, Ni, Pb in dried leaves and stems of Vinca minor, determined by AAS, were below detection limits.


Assuntos
Alcaloides , Vinca , Vincamina , Antioxidantes/farmacologia , Antioxidantes/análise , Vinca/química , Alcaloides/análise , Plantas , Minerais/análise , Folhas de Planta/química , Extratos Vegetais/análise
7.
Environ Geochem Health ; 45(11): 8403-8415, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37624440

RESUMO

Exorbitant concentrations of toxic metals in the soil from anthropogenic activities are environmental hazards and key health risk concerns to humans. The subsistence food garden soils have minimum anthropogenic interventions. The ecotoxicological risk potentials of the metals in subsistence food garden settings are unexplored. The metals (Cr, Cu, Pb, and Ni) concentration were assessed in the surface soil fractions (2 mm and 0.2 mm) of food gardens (N = 20) on the floodplains of Watut River, Papua New Guinea. The threshold limits, index of geo-accumulation (Igeo), contamination factor (CF), pollution load index (PLI), and potential ecological risk index (PERI) served as potential risk indicators of metals. Regardless of soil particle size, the descending order of median metals concentration was Cr > Cu > Ni > Pb. The concentration of Cu and Ni in the soil particles exceeded the WHO threshold limits in 100% and 50% of the food garden soils, respectively. Metal enrichment led to severe pollution in 100% gardens (Igeo > 5). Cr, Cu, and Ni contamination factors were > 1 in 95% of the food gardens. The PERI values indicated a lower ecological risk of the metals (PERI < 100). The median concentration of Cu, Igeo, and CF values for Cu in the 2 mm soil particles were significantly greater than in 0.2 mm. The results suggested exposure of subsistence food gardens soils to geogenic metal contamination and the need to carefully choose appropriate soil particle size for the soil health assessments.


Assuntos
Metais Pesados , Poluentes do Solo , Humanos , Solo , Jardins , Rios , Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Metais Pesados/análise , Papua Nova Guiné , Chumbo , Medição de Risco , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , China
8.
Sci Total Environ ; 882: 163604, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37087008

RESUMO

The geochemical behavior of metals in water and sediment was investigated in the tidal section of the Zenne River in Belgium. Twelve-hour sampling campaigns were performed in October 2013 and March 2021 at the mouth of the Zenne River, under dry and rainy weather conditions respectively. Water samples were collected every hour while the passive samplers of Diffusive Gradients in Thin-films (DGT) were deployed continuously during a tidal cycle. In addition, bottom sediments were sampled at the tidal station and water samples were taken upstream and downstream of that station to identify the metal sources. The highest concentrations of Fe, Mn, Pb, Cr, Ni and Zn appear at low tide, indicating the Zenner River as a main source. However, for Co, Cd and Cu, other sources including upstream transport may explain their behavior during a tidal cycle. Fe, Pb and Cr are essentially transported in the particulate phase (<10 % dissolved) while the other metals in the dissolved phase (20 to 90 %). Rainfall and wind gust events also play an important role in trace metal distribution, increasing sediment resuspension and metal desorption. A good agreement was found between the time-averaged dissolved and DGT-labile metal concentrations with the exception of Cu and Fe, which form strong organic Cu complexes and Fe colloids respectively. The sediments of the tidal Zenne are contaminated by trace metals, thus acting as a secondary pollution source to the river. The reductive dissolution of Mn and Fe oxyhydroxides and the release of associated trace metals are the main mobilization mechanisms. Knowledge of the upstream and downstream levels in the water column, the benthic fluxes, which are based on turbulent diffusion, and the partitioning between dissolved and particulate phases allow to explain the metal concentration variations during the tidal cycle.

9.
Environ Monit Assess ; 195(5): 583, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37072608

RESUMO

Heavy metal (HM) contamination in agricultural soils has been a serious environmental and health problem in the past decades. High concentration of HM threatens human health and can be a risk factor for many diseases such as stomach cancer. In order to investigate the relationship between HM content and stomach cancer, the under-study area should be adequately large so that the possible relationship between soil contamination and the patients' distribution can be studied. Examining soil content in a vast area with traditional techniques like field sampling is neither practical nor possible. However, integrating remote sensing imagery and spectrometry can provide an unexpensive and effective substitute for detecting HM in soil. To estimate the concentration of arsenic (As), chrome (Cr), lead (Pb), nickel (Ni), and iron (Fe) in agricultural soil in parts of Golestan province with Hyperion image and soil samples, spectral transformations were used to preprocess and highlight spectral features, and Spearman's correlation was calculated to select the best features for detecting each metal. The generalized regression neural network (GRNN) was trained with the chosen spectral features and metal containment, and the trained GRNN generated the pollution maps from the Hyperion image. Mean concentration of Cr, As, Fe, Ni, and Pb was estimated at 40.22, 11.8, 21,530.565, 39.86, and 0.5 mg/kg, respectively. Concentrations of As and Fe were near the standard limit and overlying the pollution maps, and patients' distribution showed high concentrations of these metals can be considered as stomach cancer risk factors.


Assuntos
Metais Pesados , Tecnologia de Sensoriamento Remoto , Poluentes do Solo , Neoplasias Gástricas , Humanos , Arsênio/análise , China/epidemiologia , Monitoramento Ambiental/métodos , Chumbo/análise , Metais Pesados/análise , Níquel/análise , Medição de Risco , Solo/química , Poluentes do Solo/análise , Neoplasias Gástricas/epidemiologia
10.
Vet Med Sci ; 9(4): 1592-1598, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37067509

RESUMO

BACKGROUND: In recent years, the mare's milk has been introduced as a rich source of nutrients with hypoallergic characteristics which is widely used for Iranian infants. OBJECTIVES: The present study aimed to investigate the heavy metal concentration of mare's milk and its consumption risk assessment. METHODS: About 88 mare's milk was collected from Yazd, the centre of Iran, during the summer of 2020. The raw mare's milk was digested and analysed for mineral and heavy metal content (As, Ca, Cd, Co, Cu, Fe, Mg, Mn, Ni, P, Pb and Zn) by ICP-OES. To estimate the health hazard for consumers the Estimated Daily Intake (EDI), Hazard Quotient (HQ) and Hazard Index (HI) of heavy metals were determined. RESULTS: The Ca ranged from 260.52 to 201.43 mg/L, which was the highest mineral in mare's milk followed by P and Mg. By increasing the age, P and Ca content was increased. The obtained ranges of Cu, Co, Fe, Mn and Zn were 72.12-75.11, 1.12-9.3, 180.69-230.21, 31.24-47.13 and 1060-1200 µg/L, respectively. The Cd and Arsenic content of mares' 8-11 years of age had higher concentrations. The highest Pb content was reported in mares 4-7 years old (10 µg/L). Although, Pb, Cd and As content of the mare's milk was evaluated lower than the permissible limit. Also, the HQ value was As > Cd > Pb > Zn > Ni > Cu for infants, toddlers and adults. The HI of mare's milk was 0.16, 0.15 and 0.022 for infants, toddlers and adults, respectively. CONCLUSIONS: Mare's milk could be an effective nutrition source for infants and children suffering from milk protein allergies.


Assuntos
Cádmio , Metais Pesados , Cavalos , Animais , Feminino , Irã (Geográfico) , Cádmio/análise , Chumbo , Metais Pesados/análise , Minerais/análise , Medição de Risco
11.
Sci Total Environ ; 882: 163652, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37094683

RESUMO

Health risk posed by ultrafine particles (UFPs) is potentially increased by reducing substances present in lung fluid, although knowledge of the underlying mechanisms is insufficient. Here, UFPs mainly consisting of metals and quinones were prepared. The reducing substances examined included lung endogenous and exogenous reductants. UFPs were extracted in simulated lung fluid containing reductants. Extracts were used to analyze metrics relevant to health effects, including the bioaccessible metal concentration (MeBA) and oxidative potential (OPDTT). The MeBA of Mn (974.5-9896.9 µg L-1) was higher than those of Cu (155.0-599.6 µg L-1) and Fe (79.9-500.9 µg L-1). Correspondingly, UFPs containing Mn had higher OPDTT (2.07-12.0 pmol min-1 µg-1) than those containing Cu (2.03-7.11 pmol min-1 µg-1) and Fe (1.63-5.34 pmol min-1 µg-1). Endogenous and exogenous reductants can increase MeBA and OPDTT, and the increments were generally higher for composite than pure UFPs. Positive correlations between OPDTT and MeBA of UFPs in the presence of most reductants emphasized the importance of the bioaccessible metal fraction in UFPs for inducing oxidative stress by reactive oxygen species (ROS)-generating reactions between quinones, metals, and lung reductants. Present findings provide novel insight into the toxicity and health risks of UFPs.


Assuntos
Poluentes Atmosféricos , Material Particulado , Material Particulado/toxicidade , Material Particulado/análise , Substâncias Redutoras , Estresse Oxidativo , Metais , Pulmão , Quinonas , Tamanho da Partícula
12.
Environ Sci Pollut Res Int ; 30(14): 41570-41580, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36633743

RESUMO

Epidemiological studies using conventional statistical methods have reported an association between individual metal exposure and hyperuricemia (HUA). There is also evidence that diet may influence HUA development, although the available data are inconsistent. We therefore used an elastic net regression (ENR) model to screen the usefulness of various environmental and dietary factors as predictors of HUA in a large sample cohort. This study included 6217 subjects drawn from the Shenzhen Aging Related Disorder Cohort. We obtained information on the subjects' dietary habits via face-to-face interviews and used inductively coupled plasma mass spectrometry (ICP-MS) to measure the urinary concentrations of 24 metals to which elderly persons in large urban areas may be exposed. An elastic net regression (ENR) model was generated to screen the utility of the metals and dietary factors as predictors of HUA, and we demonstrated the superiority of the ENR model by comparing it to a traditional logistic regression model. The identified predictors were used to create a clinically usable nomogram for identifying patients at risk of developing HUA. The area under curve (AUC) value of the final model was 0.692 for the training set and 0.706 for the test set. Important predictors of HUA were Zn, As, V, and Fe as well as consumption of wheat, beans, and rice; the corresponding estimated odds ratios and 95% confidence intervals were 1.091 (0.932,1.251), 1.190 (1.093,1.286), 0.924 (0.793,1.055), 0.704 (0.626,0.781), 0.998 (0.996,1.001), 0.993 (0.989,0.998), and 1.001 (0.998,1.002), respectively. In contrast to previous studies, we found that both urinary metal concentrations and dietary habits are important for predicting HUA risk. Exposure to specific metals and consumption of specific foods were identified as important predictors of HUA, indicating that the incidence of this disease could be reduced by reducing exposure to these metals and promoting improved dietary habits.


Assuntos
Hiperuricemia , Humanos , Idoso , Hiperuricemia/epidemiologia , Inteligência Artificial , Fatores de Risco , Modelos Logísticos , Comportamento Alimentar
13.
Environ Geochem Health ; 45(5): 2309-2327, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35947312

RESUMO

Paddy plants (Oryza sativa) contaminated with metals could be detrimental to human health if the concentrations of metals exceed the permissible limit. Thus, this study aims to assess the risk of the concentrations of As, Se, Cu, Cr, Co, and Ni and their distributions in various parts (roots, stems, leaves, and grains) of paddy plants collected from Sekinchan, Malaysia. Both soil and plant samples were digested according to the United States Environmental Protection Agency (USEPA) Method 3050B and the metal concentrations were determined by the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The highest mean translocation factor (TF) was from soil to roots (TF roots/soil ranged from 0.12 to 6.15) and the lowest was from leaves to grain (TF grain/leaves ranged from 0.06 to 0.87). Meanwhile, the bioaccumulation factor (BAF) for all metals was less than 1.0 indicating that paddy plants only absorb metals from the soil but do not accumulate in the grains. The average daily intake for As (1.15 ± 0.25 µg/kg/day) has exceeded the limit proposed by ATSDR and IRIS USEPA (0.30 µg/kg/day). Target cancer risk (TR) of 1.10 × 10-3 for As through rice consumption indicates that the potential cancer risk exists in one out of 1000 exposed individuals. The results from this study could serve as a reference for researchers and policymakers to monitor and formulate strategies in managing As and other metals in paddy plants, especially in Southeast Asian countries.


Assuntos
Metais Pesados , Neoplasias , Oryza , Poluentes do Solo , Humanos , Metais Pesados/toxicidade , Metais Pesados/análise , Oryza/química , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Solo/química , Risco , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Medição de Risco , Monitoramento Ambiental
14.
Sci Total Environ ; 860: 160511, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36442635

RESUMO

Hyperspectral remote sensing has the advantages to predict and map soil heavy metal concentration over conventional monitoring methods and multispectral remote sensing. In quantitative applications of hyperspectral remote sensing imagery, the contribution of hyperspectral bands is different, and abnormal prediction values resulted from incorrectly classified bare soil images are a major problem. In this study, a variable weighting method was proposed to weight the hyperspectral bands, and a probability threshold was used to improve the classification to mitigate the problem of abnormal prediction values. The variable weighting was conducted by using the absorption depths obtained by continuum removal. Soil samples were collected from a mining area in southwestern China. Hyperspectral remote sensing imagery was acquired by the Advanced Hyperspectral Imager (AHSI) abroad on Geofen-5 (GF-5) satellite. Genetic algorithm and partial least squares regression (PLSR) were adopted to calibrate prediction models. In prediction of soil copper (Cu) concentration, root mean square error (RMSE) and coefficient of determination (R2) were 21.59 mg kg-1 and 0.60 for the prediction using raw reflectance spectra, and the values were improved to 18.33 mg kg-1 and 0.71 by using the weighted reflectance spectra. The developed prediction model was applied to the AHSI imagery to predict Cu concentration in bare soil areas. In prediction of Cu concentration using the AHSI imagery, negative prediction values were eliminated by using the bare soil image extracted by the improved classification. Based on the prediction, soil Cu concentration map was generated by kriging spatial interpolation. The result indicates that the proposed variable weighting method is effective and the problem of abnormal prediction values could be mitigated by using improved bare soil images. Further analysis indicates that some indices with proper thresholds also could be used to get improved bare soil images.


Assuntos
Cobre , Solo , Tecnologia de Sensoriamento Remoto/métodos , Imageamento Hiperespectral , Mineração
15.
J Environ Manage ; 326(Pt B): 116836, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36435130

RESUMO

Renewable energy generation varies frequently, making it difficult to match electricity demand. Pumped storage hydropower plants can alleviate this problem by reducing the unevenness of renewable energy generation. It is a new exploration of energy storage methods to construct pumped storage hydropower plants by using underground goaf of abandoned mines and mining subsidence water area. However, the construction of lower reservoirs using underground goaf areas of abandoned mines can lead to potential heavy metal pollution. To assess the impact of using abandoned mines for pumped storage hydropower on the downstream surface water environment, this work first analyzed the release characteristics of heavy metals from underground goaf and surface dump through field sampling and leaching tests, then constructed a water-environment model of the downstream surface water based on the experimental results and water environment theory, and finally simulated and analyzed the impact of underground pollutants pumped to the surface on downstream surface water-quality in typical hydrological years. The maximum error between the simulated values and measured values of the hydrodynamic model was 0.1, and the overall error was within a reasonable range (±0.2 m). The comparison between simulated values and measured values of heavy metal concentration in water quality model showed RMSE values ranged from 0.003 to 0.81, with an average of 0.4; the SI ranged from 0.84 to 0.95, with an average of 0.89. During the simulation of low, normal, and high flow years, pollution downstream was concentrated near the drainage outlet, and the underground pollutants pumped to the surface influenced the concentration of heavy metals there. After a period of drainage, the concentration of heavy metals decreased. Drainage volume was an important factor affecting the concentration of heavy metals downstream surface water. These results prove that the water environment model established based on MIKE21 is reliable and can provide guidance for the simulation and control of heavy metal pollution in the utilization of abandoned mines for pumped storage hydropower. This work provides a reproducible idea and method to assess the impact of using abandoned mines and mining subsidence water area for pumped storage hydropower on downstream surface water and ensure the safety of the ecological environment.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes do Solo , Mineração , Metais Pesados/análise , Poluição Ambiental , Meio Ambiente , Monitoramento Ambiental , Poluentes do Solo/análise
16.
J Hum Reprod Sci ; 16(4): 317-323, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38322633

RESUMO

Background: There is ongoing research to find an optimum modality to predict male fertility potential. Aims: To compare the semen parameters, sperm DNA damage and seminal metal levels of Zinc, Lead and Aluminium among the male partners of couples with unexplained infertility and men with proven fertility. Settings and Design: Prospective case-control study at a tertiary level teaching hospital. Materials and Methods: One hundred male partners of couples with unexplained subfertility and 50 men with proven fertility were included in the study. Male partners of unexplained infertility couples and fertile men were compared for their semen parameters, sperm DNA Fragmentation Index (DFI) and seminal metal levels in semen. Statistical Analysis Used: Chi-square test, Student's t-test, sensitivity and specificity analysis, binomial logistic regression analysis. Results: Fertile men had statistically significantly higher mean progressive sperm motility than male partners of unexplained infertility (53.12 ± 9.89% vs. 44.81 ± 19.47%, P = 0.005). Semen volume and sperm concentration were comparable among the cases and control population. The mean sperm DFI was significantly lower among fertile men (10.83 ± 6.28 vs. 21.38 ± 10.28, P < 0.0001). Plotting the receiver-operating characteristic curve the threshold for discrimination was calculated to be 18% DFI. The sensitivity specificity and overall accuracy were 43%, 84% and 56.67%, respectively when the DFI cut-off was set at 18%. Zinc concentration in the semen had a strong positive correlation (Point Biserial correlation coefficient = 0.831) with fertility, whereas lead and aluminium had a moderate negative correlation. Conclusion: Conventional semen analysis had limited differentiating ability for unexplained infertility. The sperm DFI may be employed for explanatory purposes among couples with unexplained subfertility. A lower discriminatory threshold of DFI (18%) has better overall accuracy as opposed to a 30% cutpoint for unexplained subfertility. Among metals, Zinc was strongly correlated with fertility status.

17.
Heliyon ; 8(11): e11451, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36406724

RESUMO

The combination of electro-enhanced and hydroponic phytoremediation hereinafter referred to as electro-enhanced phytoremediation (EP) system, has been employed for rapid removal of trace metal concentration of lead (II) from contaminated water using Kentucky bluegrass (Poa pratensis L.) as accumulator plant. In this study, for rapid assessment the effectiveness of two-dimensional (2D) electrode configuration in electro-enhanced system was evaluated by agar media for 48h period of time. Furthermore, these configurations were applied to enhance the EP system for 9d period of time. Also, a common agrochemical-urea as chaotropic agent to facilitate the healthy growth of plant in contaminated water was evaluated. The results showed that the accumulation of lead (II) concentration was higher in the plant roots (i.e. high bioaccumulation coefficient (BC) value) than in aerial parts of plant (i.e. low translocation factor (TF) value). Also, the accumulation of lead (II) concentration in plant was higher under the treated urea of EP system. The chlorophyll content, biomass accumulation productivity, and water content (i.e. dry weight-fresh weight (DW/FW) ratio) of plant either under the treated urea or untreated urea with high accumulation of lead (II) concentration revealed that the Kentucky bluegrass has able to hold out the plant stress.

18.
Biomass Convers Biorefin ; : 1-20, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36406949

RESUMO

As a fossil fuel substitute, bio-jet fuel derived from inedible oilseed crops has the potential to improve energy security, decrease carbon footprint, and promote agricultural economy and social development. The efficient production of bio-jet fuels depends on the identification and characterization of eco-friendly and sustainable feedstocks. Brassica carinata (Arun Braun) cultivars are among the most significant industrial oilseeds that can be utilized as alternative feedstocks in the aviation industry. The study thoroughly evaluated four non-food Brassica carinata cultivars that are indigenous to Ethiopia to determine their suitability as substitute feedstocks for the production of bio-jet fuel. The effects of solvent extraction parameters were studied using response surface methodology with Box-Behnken design in an isothermal batch reactor. Physicochemical characterization, fatty acids profiling, ultimate analysis, analysis of metals and phosphorus concentration, Fourier-transform infrared spectroscopy characterization, and calorific value analyses were performed to characterize the properties of oils. Accordingly, oil yields ranged from 35.93 to 45.25%. Erucic acid (EA) was the most predominant fatty acid in all oils, accounting for 42-50%, of Derash and Yellow Dodolla oils, respectively, making Yellow Dodolla oil a super-high erucic acid oil. In comparison to the other oils, Yellow Dodolla was observed to be the least oxygenated oil, with a 7.80% oxygen content and oxygen to carbon ratio of 0.07, which may enable it to consume a very limited amount of hydrogen gas during hydrodeoxygenation in bio-jet fuel production. It was determined that, except for calcium and phosphorous levels in Tesfa, the concentrations of the metals and phosphorous were very small. Alkanes, alkenes, carboxylic acids, esters, alcohols, aromatics, and olefins were among the most significant and main functional groups identified. Our extraction and characterization results revealed that the Brassica carinata cultivars have very high oil contents, better physicochemical properties, excellent fatty acid profiles, and very low concentrations of heteroatoms (nitrogen, sulfur), metals and phosphorous concentrations, and very low level of oxygen to carbon ratios, making the oils, notably Yellow Dodolla oil, very high quality and promising alternative feedstocks for upgrading of the oils into bio-jet fuels through hydroprocessing pathway.

19.
Toxics ; 10(10)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36287890

RESUMO

In this paper, simulation experiments were conducted to study the response of phytoplankton biomass and community composition to the influence of polymetallic nodules and sediment at four stations in the western Pacific in 2021. Chlorophyll a, pico-phytoplankton cell abundance, and metal concentration were measured before and after 24 h of deck incubation. The results show that there were three different patterns of response, namely, restrained, stimulated, and unaffected patterns. The restrained pattern appeared in the filtered treatments at station Incub.01, and the stimulated pattern appeared in the unfiltered treatments at station Incub.02. The response of the phytoplankton was not detectable at stations Incub.03 and 04. Regardless, positive and negative responses were found in the dominant pico-phytoplankton group-Prochlorococcus-and with slight variation in Synechococcus. The concentration of manganese varied among the treatments compared to that of iron and other metals. The factors affecting the growth of the phytoplankton in this study were metal concentrations and turbidity. The phytoplankton biomass baseline may also have played an important role: the lower the biomass, the higher the growth rate. This study proved that deep-sea polymetallic nodule mining will have a specific impact on surface phytoplankton biomass, but turbidity and particle retention time could be important factors in mitigating the extent of the impact.

20.
Ecotoxicol Environ Saf ; 242: 113904, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35882109

RESUMO

Traditional Chinese medicine (TCM) has accumulated a wealth of ecological wisdom and is regarded as an outstanding cultural and medical resource in China. However, in the context of serious environmental pollution, the potential harm caused by TCM materials (TCMMs) due to toxic heavy metals has seriously affected the sustainable development of TCM. Cadmium (Cd) is an internationally recognized heavy metal contaminant. In this paper, 270 reports on Cd in TCMMs were screened from 1969 publications covering 243 species in 81 families. According to the source of the TCMMs, the data were divided into the following categories: aboveground part, bark, flower and fruit, herb, leaf and rhizome. The temporal dynamics of the Cd content and its correlations with the habitats and categories (parts) of TCMMs were also studied. The results show that 22.05 % of the investigated TCMM samples exceeded the relevant domestic standards (Cd≤0.3 mg/kg), among which the maximum Cd content was 17.75 mg/kg. Myrtaceae and Syzygium aromaticum were the family and species with the highest mean Cd content, respectively. Regarding the source of TCMMs of great concern, the mean Cd content of TCMMs decreased in the order of herb > aboveground part > flower and fruit > leaf > rhizome > bark. In addition, in terms of the spatiotemporal distribution, the spatial distribution of the mean Cd content of TCMMs was significantly higher on the Qinghai-Tibet Plateau, followed by Southwest China. When comparing different times, more serious Cd pollution of TCMMs existed after 2000, and the highest mean Cd content was observed in 2000-2004. In summary, soil acidity must be decreased and the cultivation conditions of Cd-hyperaccumulators such as Ligusticum chuanxiong and Lonicera japonica must be modified, in conjunction with a scientific health risk assessment, to ensure the sustainable development of TCMMs.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/análise , China , Monitoramento Ambiental/métodos , Humanos , Medicina Tradicional Chinesa , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
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