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1.
Food Chem ; 398: 133822, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35961169

RESUMO

A portable device is conducive to the on-site detection of heavy metal ions at trace level in food and the prevention of related food safety issues. In this work, an electrochemical device stacked up with flat electrodes was developed for the detection of Pb2+ and Cd2+. The top layer of the device is a carbon paper as working electrode, which is modified with amino functionalized cobalt-based metal-organic framework and gold nanoparticles. The bottom layer was constructed with the carbon counter electrode and Ag/AgCl reference electrode, and a punched sample cell (Φ = 8 mm) was in the middle. The proposed method could simultaneously determinate Pb2+ and Cd2+ via anodic stripping voltammetry with the detection limit of 7.0 × 10-2 ng mL-1 and 1.1 × 10-2 ng mL-1, and was applied in real food samples (drinking water, juice, tea, grain, fruits, vegetables, liver and aquatic products) with the recovery of 91.2-105.4 % and 90.2-111.2 %, respectively.


Assuntos
Nanopartículas Metálicas , Estruturas Metalorgânicas , Cádmio , Carbono , Eletrodos , Ouro , Íons , Chumbo
2.
Food Chem ; 398: 133866, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35964561

RESUMO

Seaweeds are a rich source of nutritional and functional compounds, but they also accumulate heavy metals. Here, the chemical composition (crude protein, total lipids, Nitrogen Free Extract and fiber) and the presence of minerals (Na, K, Ca, Mg, P, Fe, Mn, Cu, Zn, Mo, Se) and unwanted elements (As, Cd, Hg, Pb, Ni, Cr, Al) were determined in eleven seaweeds from Chile. Depending on the species, a good contribution to the Recommended Dietary Allowance for K, Ca, Mg, Fe, Mn and Se was observed, and low Na/K ratios (<1.0) as well. The health risk assessment indicated low hazard due to intake of seaweed meal. The mean values of As, Hg, and Pb were below the maximum limits set for food supplements and feed ingredients. The seaweeds studied have a suitable chemical composition for their uses as food and feed ingredients, although Cd levels should be monitoring especially in brown seaweeds.


Assuntos
Mercúrio , Metais Pesados , Alga Marinha , Cádmio/metabolismo , Chile , Monitoramento Ambiental , Chumbo/metabolismo , Mercúrio/metabolismo , Metais Pesados/análise , Alga Marinha/química
3.
Braz. j. biol ; 83: e248828, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339354

RESUMO

Abstract Serum toxic metals have been implicated in development of many diseases. This study investigated the association between blood levels of lead and cadmium with abnormal bone mineral density (BMD) and incidence of osteoporosis. Sixty Saudi male adults age matching were assigned into two groups: A healthy control group (n = 30) and osteoporosis patients diagnosed according to T-score (n = 30). Serum calcium, vitamin D, osteocalcin, lead, cadmium were measured. Osteoporotic group showed a highly significant elevation of blood lead and cadmium levels compared to the control group (p <0.001). BMD was negatively correlated with serum osteocalcin level compared with control. There was a significant negative correlation between the cadmium and lead levels (r=-0.465 and p-value = 0.01) and calcium (p < 0.004). Our findings suggested that high cadmium and lead were negative correlated to BMD and increased the risk factor for osteoporosis.


Resumo Os metais tóxicos do soro têm sido implicados no desenvolvimento de muitas doenças. Este estudo investigou a associação entre os níveis sanguíneos de chumbo e cádmio com densidade mineral óssea anormal (DMO) e incidência de osteoporose. Sessenta adultos sauditas do sexo masculino com idades iguais foram divididos em dois grupos: um grupo de controle saudável (n = 30) e pacientes com osteoporose diagnosticados de acordo com o T-score (n = 30). Cálcio sérico, vitamina D, osteocalcina, chumbo, cádmio foram medidos. O grupo osteoporótico apresentou elevação altamente significativa dos níveis de chumbo e cádmio no sangue em comparação ao grupo controle (p < 0,001). A DMO foi negativamente correlacionada com o nível de osteocalcina sérica em comparação com o controle. Houve correlação negativa significativa entre os níveis de cádmio e chumbo (r = -0,465 ep = 0,01) e cálcio (p < 0,004). Nossos achados sugeriram que cádmio e chumbo elevados foram correlacionados negativamente à DMO e aumentaram o fator de risco para osteoporose.


Assuntos
Humanos , Masculino , Adulto , Osteoporose/epidemiologia , Chumbo , Arábia Saudita/epidemiologia , Absorciometria de Fóton , Osteocalcina , Incidência
4.
Environ Pollut ; 302: 119062, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35231537

RESUMO

Lead is a metal that exists naturally in the Earth's crust and is a ubiquitous environmental contaminant. The alleviation of lead toxicity is important to keep human health under lead exposure. Biosynthesized selenium nanoparticle (SeNPs) and selenium-enriched Lactobacillus rhamnosus SHA113 (Se-LRS) were developed in this study, and their potentials in alleviating lead-induced injury to the liver and intestinal tract were evaluated in mice by oral administration for 4 weeks. As results, oral intake of lead acetate (150 mg/kg body weight per day) caused more than 50 times and 100 times lead accumulation in blood and the liver, respectively. Liver function was seriously damaged by the lead exposure, which is indicated as the significantly increased lipid accumulation in the liver, enhanced markers of liver function injury in serum, and occurrence of oxidative stress in liver tissues. Serious injury in intestinal tract was also found under lead exposure, as shown by the decrease of intestinal microbiota diversity and occurrence of oxidative stress. Except the lead content in blood and the liver were lowered by 52% and 58%, respectively, oral administration of Se-LRS protected all the other lead-induced injury markers to the normal level. By the comparison with the effects of normal L. rhamnosus SHA113 and the SeNPs isolated from Se-LRS, high protective effects of Se-LRS can be explained as the extremely high efficiency to promote lead excretion via feces by forming insoluble mixture. These findings illustrate the developed selenium-enriched L. rhamnosus can efficiently protect the liver and intestinal tract from injury by lead.


Assuntos
Enteropatias , Lactobacillus rhamnosus , Selênio , Animais , Chumbo/toxicidade , Fígado , Camundongos , Selênio/farmacologia
5.
Plant Physiol Biochem ; 189: 104-114, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36081232

RESUMO

Cadmium (Cd) and lead (Pb) pollution is a major environmental issue affecting plant production. Spermidine (Spd) is involved in plant response to abiotic stress. However, the role and associated mechanism of Spd under Cd + Pb combined stress are poorly understood. The potential protective role of Spd at different concentration on rice (Oryza sativa L.) seedlings exposed to Cd + Pb treatment was investigated by a hydroponic experiment in this study. The results showed that exogenous Spd enhanced the tolerance of rice seedlings to Cd + Pb stress, resulted in an increase in plant height, root length, fresh weight and dry weight of roots and shoots. Further, application of Spd decreased the contents of hydrogen peroxide, superoxide anion, malondialdehyde, and the accumulation of Cd and Pb, and increased the contents of mineral nutrient, carotenoids, chlorophyll, proline, soluble sugar, soluble protein, total phenol, flavonoid, anthocyanin, and antioxidant enzymes activities in roots and shoots of rice seedlings under Cd + Pb stress. Particularly, 0.5 mmol L-1 Spd was the most effective to alleviate the adverse impacts on growth and physiological metabolism of rice seedlings under Cd + Pb stress. Principal component analysis and heat map clustering established correlations between physio-biochemical parameters and further revealed Spd alleviated Cd + Pb damage in rice seedling was associated with inhibition of accumulation and translocation of Cd and Pb, increasing the contents of photosynthetic pigments and mineral nutrient and stimulation of antioxidative response and osmotic adjustment. Overall, our findings provide an important prospect for use of Spd in modulating Cd + Pb tolerance in rice plants. Spd could help to alleviate Cd + Pb damage through inhibition of accumulation and translocation of Cd and Pb and stimulation of oxidant-defense system and osmotic adjustment.


Assuntos
Oryza , Antocianinas/metabolismo , Antioxidantes/metabolismo , Cádmio/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Peróxido de Hidrogênio/metabolismo , Chumbo/metabolismo , Malondialdeído/metabolismo , Oryza/metabolismo , Oxidantes/metabolismo , Oxidantes/farmacologia , Fenóis/metabolismo , Raízes de Plantas/metabolismo , Prolina/metabolismo , Plântula/metabolismo , Espermidina/metabolismo , Espermidina/farmacologia , Açúcares/metabolismo , Superóxidos/metabolismo
6.
Environ Monit Assess ; 194(10): 792, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36107258

RESUMO

Indices of contamination (IC) are usually employed to assess the hazardousness associated with potentially toxic elements (PTE) from mining wastes (MW). For such, it is necessary to know the total concentrations of the PTE and local, regional, or global background or reference levels which are tolerable or acceptable threshold values for total content in soils. Although scientific literature is vast regarding the application of IC to MW, there is scarce research on the reference levels that must be employed in locations with no established comparison values. This study proposes basic reference levels for the global application of PTE contents in MW, leading to a global index of contamination (ICG). To this end, it was determined that the PTE to be assessed in MW should be As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Se, V, and Zn. From the analysis of background and baseline values for soils, reference values for the PTE compiled from worldwide standards or studies on soil and sediment evaluation, and PTE content in MW, a classification is proposed for ICG that considers MW as very low, low, moderate, high, and very high contamination potential. The findings presented herein can be helpful in the comparison of multiple types of MW, representing the contamination hazard by particle emission due to erosion processes that reach the soils or sediments of the surrounding environment. This evaluation can aid in the decision-making process regarding the reutilization of some types of MW that receive a low classification.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Cádmio/análise , Monitoramento Ambiental , Chumbo/análise , Mercúrio/análise , Metais Pesados/análise , Solo , Poluentes do Solo/análise
7.
Schizophr Res ; 247: 33-40, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36075821

RESUMO

Accumulating evidence from observational studies, genetic research, and animal models suggests a relationship between toxic and nutritive elements and psychotic spectrum disorders (PSD). This review systematically evaluates the current research evidence for two hypotheses: 1) that exposures to abnormal levels of toxic and nutritive elements early in life contributes to the subsequent development of PSD, and 2) that an imbalance of element levels is linked to psychotic illness and clinical severity. We focused on the extant literature on five elements, lead (Pb), copper (Cu), magnesium (Mg), manganese (Mn), and zinc (Zn), because of their previously documented associations with psychiatric problems and the availability of pertinent literature. The review identified 38 studies of which 11 measured Pb, 27 measured Cu, 16 measured Mg, 15 measured Mn, and 25 measured Zn concentrations in PSD patients and controls. A majority of research has been conducted on nutritive element imbalance, and findings are largely mixed. While it is biologically plausible that element dysregulation is an important modifiable risk factor for PSD, more research into exposure in early life is needed to better characterize this relationship.


Assuntos
Cobre , Manganês , Cádmio , Chumbo , Magnésio , Manganês/toxicidade , Zinco
8.
Sci Rep ; 12(1): 15602, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114237

RESUMO

Studying highly valuable and fragile Renaissance drawings requires a non-invasive contactless analytical approach. In this work, we study an early drawing by Raffaello Sanzio, one of the most important artists of the Italian Renaissance, realized during his stay in Florence (1504-1508). Our analyses aimed to reveal the features of the paper support significant for its dating, identify and map the drawing media to understand the artist's technical approach, and document the drawing condition with imaging and single-sited optical methods. Reflectance Vis-NIR multispectral imaging spectroscopy elaborated with False-Colour and Principal Component Analysis provided information about the paper support and the drawing media. Laser scanning micro-profilometry and Optical Coherence Tomography allowed revealing the superficial micro-scale features of the support. The chemical composition of the different drawing materials was characterized by µ-Raman spectroscopy, which provided also some evidence of the conservation history of the drawing. Integration of spectroscopic and imaging data shows that Raffaello used different dry drawing media (carbon-based and Pb stylus) to sketch the figure and then refined the details and shadows with iron-gall ink. The paper presents a methodological approach for the analytical examination of fragile paper artworks.


Assuntos
Arte , Chumbo , Itália , Análise Espectral Raman/métodos , Tomografia de Coerência Óptica
10.
J Nutr Sci ; 11: e72, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36106088

RESUMO

In the present study, the levels and probable public health risks of selected metals (Fe, Mn, Cu, Zn, Ni, Cd and Pb) in nine wheat flour samples collected from Amhara, Oromia, South region, and the Strategic Food Reserve Agency were determined using FAAS and compared with results of prior studies and critical level. The wet digestion method using 65 % HNO3 and 72 % HClO4 in 300°C for 3 h was used when preparing the sample. Validation of the optimised digestion method was assessed using the spiking method, and an acceptable percent recovery from all metals. The levels of Fe, Cu, Mn, Zn, Ni and Cd ranged between 8⋅5297 and 11⋅1535, 1⋅633 and 4⋅2346, 3⋅1875 and 8⋅5313, 2⋅3589 and 2⋅7719, 0⋅154 and 0⋅854, and 0⋅0411 and 0⋅216 mg/kg, respectively, for Ethiopian wheat flour, while the level of Fe, Cu, Mn, Zn, Ni, Cd and Pb were ranged between 8⋅0099 and 8⋅1089, 1⋅663 and 1⋅6691, 4⋅5625 and 4⋅6250, 2⋅3015 and 2⋅3072, 0⋅9423 and 1⋅1346, 0⋅1593 and 0⋅1606, and 0⋅13 and 0⋅1381 mg/kg, respectively, for imported wheat flour. However, Pb had a concentration of less than 0⋅043 mg/kg for Ethiopian wheat flour. Findings indicate that Ethiopian wheat is comparatively higher in Fe, Mn, Cu, Zn and Cd, but lower in Ni and Pb than imports. From the result of the study, it can be concluded that the level of heavy metals determined in this study was within the permissible limit, and no probable health risk because both the Hazard quotient (HQ) and the Hazard Index (HI) are found to be below 1⋅0 regarding study metals.


Assuntos
Farinha , Triticum , Cádmio , Etiópia , Chumbo
11.
Huan Jing Ke Xue ; 43(9): 4532-4542, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096594

RESUMO

The morphological characteristics of Cd, Cr, Cu, Ni, Pb, and Zn in sediments were analyzed using an improved BCR extraction method in four water types of Baiyangdian Lake:watercourse, trench, lake surface, and fish pond. The potential ecological risk index, secondary and primary phases, and risk assessment codes were used to systematically assess the pollution level and ecological risk of heavy metals in surface sediments. The results showed that:① the mean contents of heavy metals Cd, Cu, and Zn in the sediments were 0.37, 28.49, and 83.08 mg·kg-1, respectively, 94.91%, 73.91%, and 46.39% of which exceeded the soil background value. ② Cd was dominated by the non-residual fraction (F1+F2+F3) with a fraction ranging from 54% to 97%, whereas Cr was dominated by the residual fraction (F4) with a mass fraction ranging from 87% to 99%. Cu, Ni, Pb, and Zn were mainly in the fraction of residual fraction. In the non-residual fraction, Cu and Ni were mainly in the oxidizable fraction (F3) state, whereas Pb and Zn were mainly in the reducible fraction (F2) state. ③ The RAC risk assessment results showed that there were 68.97%, 39.89%, 54.84%, and 49.78% points in channel, trench, open water, and fish pond samples, respectively, of Cd at high risk. The Cu, Ni, and Pb were at low risk. In general, the overall heavy metal pollution level in Baiyangdian Lake was low, but Cd had ecological risk and high bioavailability in the Fuhe River of the Nanliuzhuang area and the Baigouyin River.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Cádmio , Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Chumbo , Metais Pesados/análise , Água , Poluentes Químicos da Água/análise
12.
Huan Jing Ke Xue ; 43(9): 4767-4778, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096617

RESUMO

Heavy metals in cultivated soil may migrate and transform through the food chain to harm the ecological environment and human health. At present, the ecological environment and human health risks of heavy metals in cultivated soil in Lanzhou city remain unclear, which impacts the effective management and control of heavy metals. The potential ecological risk hazard index was used to evaluate the ecological environmental risks of As, Cd, Cr, Hg, and Pb in the surface soil of cultivated land in Lanzhou, and the health risk model proposed by USEPA and the recommended standard were used to evaluate their human health risk. The main factors influencing the spatial differentiation of human health risk were explored by using geographic detectors. The risk of heavy metals to the ecological environment of the cultivated land surface soil in the study area was mainly medium (65.25%), and small portions were low (13.80%) and high (20.95%). The low-risk areas were mainly located in the southeast of Yongdeng County, the middle and north of Yuzhong County, and the southwest of Gaolan County. Moderate risk areas were distributed in three counties and five districts. The high-risk areas were located in the north and southeast of Yongdeng County, the south of Chengguan District, the northeast of Qilihe, the east of Xigu District, and the middle of Yuzhong County. The non-carcinogenic and carcinogenic risks of five types of heavy metal exposure pathways were as follows:oral ingestion>skin contact>respiratory ingestion; generally speaking, children were at higher risk than adults. The non-carcinogenic risk in children was higher than that in adults; however, there was no such risk for local residents, as they were all less than 1. At the same time, the carcinogenic risk of As was greater than 1×10-5 (children 2.04×10-5) and less than 1×10-4 (adults 1.91×10-5), respectively. This indicated an acceptable medium risk to the local residents, and the risk to children was again greater than that to adults. Geographical detector analysis showed that average precipitation during the sampling season had the greatest impact on the spatial differentiation of human health risks of As and Cd, GDP had the greatest impact on the spatial differentiation of human health risks of Cr, and distance from the railway had the greatest impact on the spatial differentiation of human health risks of Hg and Pb. Interaction detection showed that all factors were enhanced by double factors. In addition to leading factors, other factors such as pH, slope, and altitude also enhanced the influence of leading factors on the spatial differentiation of heavy metal risk in cultivated soil.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Adulto , Cádmio/análise , Carcinógenos/análise , Criança , Monitoramento Ambiental , Humanos , Chumbo/análise , Mercúrio/análise , Metais Pesados/análise , Metais Pesados/toxicidade , Medição de Risco , Solo , Poluentes do Solo/análise
13.
Huan Jing Ke Xue ; 43(9): 4779-4790, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096618

RESUMO

In order to explore the distribution characteristics of heavy metal contamination of farmland soil surrounding Luancheng town, Shijiazhuang City, Henan province, the concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the surface soil and crops were determined and assessed. The principal components were also analyzed for source apportionment. The heavy metal concentrations in crops were further detected, and the non-carcinogenic health risks in the study area were evaluated using the probabilistic risk assessment method, as to provide a theoretical basis for the treatment, prevention, and control of heavy metal pollution in farmland soil in Luancheng. According to the results, ω(Cd), ω(Cr), ω(Cu), ω(Pb), and ω(Zn) in the soils were 0.06-1.08, 22.14-473.47, 12.83-150.74, 10.75-577.72, and 62.23-652.78 mg·kg-1, which exceeded the standard with over-standard rates reaching 1.83%, 1.22%, 0.61%, 0.61%, and 1.22%, respectively. Further, Cd and Pb were transported into crops, in which Cd concentrations exceeded the standard in some corn samples, and Cd and Pb concentrations exceeded the standard in some wheat samples. The total non-carcinogenic health risks (TTHQ) to the human body caused by the consumption of heavy metals in corn grown in the study area were all less than 1, with no obvious negative effects, and TTHQ was higher than 1 in wheat, increasing the likelihood of negative impacts on the human body. With the influence of the distribution of pollution-related enterprises in the industrial zone, heavy metal concentrations were higher in the south, west, and middle directions of the study area. Among them, the study area soil was slightly contaminated by Cd (Level 1). Cd and Hg had a slight potential ecological risk (Level 2), whereas other heavy metals had low potential ecological risk (Level 1). In general, most of the surface cultivated soil was not obviously polluted by heavy metals in the study area. According to the PMF results and survey, we speculated that soil heavy metals mainly came from soil parent material (52.05%), artificial pollution sources (historical sewage irrigation and industrial manufacture) (32.98%), and atmospheric deposition (14.97%). To summarize, the study area should be divided into a priority protection category and safe utilization category. The input of pollution sources should be strictly controlled for the priority protection category, and alternative planting, rotating, and fallow should be implemented for the safe utilization category to reduce the risk of standard-exceeding agricultural products.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Cádmio , Produtos Agrícolas , Monitoramento Ambiental , Fazendas , Humanos , Chumbo , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
14.
Huan Jing Ke Xue ; 43(9): 4800-4809, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096620

RESUMO

To investigate the soil contamination degree and potential ecological risk level of heavy metals in villages and towns in Tongling City, we collected 67 surface soil samples (including surface dusts and river sediments) from the typical districts, namely Shun'an Town, Zhongming Town, and Yi'an Economic Development Zone, and measured the contents of heavy metals including Cu, Zn, Pb, Cr, Cd, As, and Ni. Then, spatial distribution characteristics of heavy metals were analyzed, and their contamination degree and potential ecological risk were assessed. Finally, source apportionment of soil heavy metals was conducted using factor analysis. The results showed that the soil pH was weakly acidic in the study area, and the average contents of Cu, Zn, Cr, Cd, As, and Ni were 4.94, 2.89, 2.07, 0.94, 7.97, 4.03, and 2.02 times their soil background values in Tongling City, respectively. In general, the contents of soil heavy metals in the western part were higher than those in the eastern part across the studied area. According to the Nemerow pollution index, Cu, Cd, As, and Pb reached pollution levels; Zn, and Ni approached moderate pollution levels; and Cr belonged to the no pollution degree category. The Nemerow comprehensive pollution index of different land types was arranged in the order of river bed>town district>industrial land>vegetable land>agricultural land>mountain forest>village. On the whole, the contamination degree of soil heavy metals in the study area reached severe pollution levels. The order of potential ecological risk coefficients of soil heavy metals was Cd>As>Cu>Pb>Ni>Zn>Cr, in which Cd belonged to the extremely high risk level, Cu and As belonged to the medium risk level, and the others were all low risk levels. The potential ecological risk levels corresponding to different land types were as follows:river bed>town distribution>industrial land>vegetable land>agricultural land>village>mountain forest. The industrial land, vegetable land, and town district generally reached a very high risk level, and the agricultural land reached a high risk, whereas both village and mountain forest land showed a medium risk. Principal component analysis showed that Cu, Zn, Pb, Cd, and As in the study area were derived from local metal mining pollution; Cr was from both the geological background and metal mining pollution; and Ni mainly came from fossil fuel combustion.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/análise , Cidades , Monitoramento Ambiental/métodos , Chumbo/análise , Metais Pesados/análise , Mineração , Medição de Risco , Solo/química , Poluentes do Solo/análise
15.
Huan Jing Ke Xue ; 43(9): 4878-4887, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096628

RESUMO

Flotation agents can enter the soil and water environment around mining areas through beneficiation wastewater discharge and overflow from tailings ponds. The adsorption of Pb2+ and Cd2+ on soil around a lead-zinc dressing plant was investigated in the presence of potassium butyl xanthate (PBX). Batch experiments were conducted with different initial pH, PBX, Pb2+, and Cd2+solution concentrations. The fractions of lead and cadmium were altered after treatment with different concentrations of PBX. The results showed that adsorption of Pb2+and Cd2+ on soil was seriously inhibited by PBX. When PBX concentration was 40 mg·L-1, the adsorption capacity of Pb2+ and Cd2+ decreased from 3540 mg·kg-1 and 387 mg·kg-1 to 3085 mg·kg-1 and 100 mg·kg-1, respectively. The Pb2+ and Cd2+ adsorption kinetic process was best fitted by the quasi-second-order kinetic model, which indicated that the adsorption process of Pb2+ and Cd2+ on soil was mainly chemical adsorption. The formation of a hydrophobic and insoluble complex and competitive adsorption between PBX, Pb2+, and Cd2+ on the soil surface was the main reason for reducing the adsorption capacity. The results showed that PBX could increase the mobility of Pb2+ and Cd2+ on soil. The degree of impact improved with increasing initial concentration of PBX and pH but decreased with increasing initial concentration of Pb2+ and Cd2+, and the adsorption isotherms conformed to the Freundlich isotherm. Under low PBX content (100 mg·kg-1), exchangeable and reducible cadmium contents in the soil increased, which could lead to the activation of cadmium in soil. However, the addition of PBX to the treated soil could reduce the content of exchangeable and reducible lead. As the concentration of PBX increased, the reduction effect also increased, which was related to the stronger complex stability of Pb(C4H9OCS2)2 than that of Cd(C4H9OCS2)2. The results showed that residual flotation reagents in beneficiation wastewater may increase the potential ecological risk of heavy metals such as Pb and Cd in soil, and the prevention and control of the potential ecological risk should be strengthened.


Assuntos
Poluentes do Solo , Solo , Adsorção , Bandagens , Cádmio/análise , Chumbo , Poluentes do Solo/análise , Tionas , Águas Residuárias
16.
J Environ Manage ; 321: 115904, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36104879

RESUMO

A method development pilot study examining citizen science tools for assessing lead in childcare settings identified plastic food toys as an unexpected potential source of lead and arsenic. Collaborating researchers at three universities sought to develop a low cost, replicable approach for use in childcare centers to identify lead. Through graduate Environmental Health courses at Northeastern and Boston Universities, 197 Plastic Food Toys (PFTs) used in a childcare center were tested for lead using a portable X-Ray fluorescence (XRF) instrument and a colorimetric wipe method for detecting surface lead. The XRF identified concerning levels of lead and co-occurring arsenic in PFTs. The XRF analysis found 8.63% (17/197) of PFTs from the childcare center contained more than 100.00 ppm of lead, the U.S. Consumer Protection Safety Commission's (CPSC) upper regulatory threshold for lead in childrens' products. However, wipes did not detect removable surface lead. Lead concentrations ranged from 6.14 ppm to 11,999.00 ppm with a median of 40.00 ppm. Additionally, 7.10% of all PFTs tested had detectable levels of arsenic which ranged from 9.30 ppm to 1134.42 ppm and had a median value of 113.20 ppm. Arsenic concentrations in 6.60% of PFTs' exceeded the US voluntary standard for arsenic in children's products of 25.00 ppm (adopted from the EU standard). These findings prompted further sampling of similar newly-purchased PFTs. None of the newly-purchased PFTs tested positive for lead or arsenic (0/87). Several other elements were also identified, particularly in the used PFTs. Because these food-like toys are frequently put in children's mouths, we recommend further investigation of PFTs in circulation via citizen science combining the wipe and XRF method as they provide immediate data to participants. Additionally, CPSC should consider a systematic recall of some used PFTs to prevent exposure disparities by socio-economic status and increased surveillance for other toxic metals in new PFTs.


Assuntos
Arsênio , Ciência do Cidadão , Arsênio/análise , Criança , Cuidado da Criança , Intoxicação por Metais Pesados , Humanos , Chumbo/análise , Projetos Piloto , Plásticos
17.
Sci Rep ; 12(1): 15305, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097036

RESUMO

Compared with the relatively well-investigated effects of childhood exposure to lead on neurocognitive deficits, those of prenatal exposure remain relatively inconclusive. We aimed to investigate the association between prenatal blood lead levels and neurodevelopmental delay during the first three years of life. From a prospective cohort of the Japan Environment and Children's Study, we analyzed a total of 80,759 children. The exposure factors were prenatal lead concentrations measured from maternal whole blood in the second/third trimesters and umbilical cord blood at birth. Neurodevelopment was assessed at 6, 12, 18, 24, 30, and 36 months old using a screening tool, the Ages and Stages Questionnaires, third edition (ASQ). The outcome measures were any suspected neurodevelopmental delay (sNDD) identified via the ASQ during the first (sNDD-1Y), second (sNDD-2Y), and third (sNDD-3Y) years of life. sNDD-1Y, 2Y, and 3Y were identified in 18.0%, 16.2%, and 17.2% of children, respectively. The geometric means of blood lead concentration in this study were much lower (0.62 µg/dL in maternal blood and 0.50 µg/dL in cord blood) than previously investigated levels. Multivariable regression models revealed that there were no associations between maternal blood lead and sNDD-1Y and 2Y and between cord blood lead and sNDD-1Y, 2Y, and 3Y. Although a higher maternal blood lead was associated with a reduced risk of sNDD-3Y (adjusted relative risk: 0.84, 95% confidence interval 0.75-0.94, per 1 increase in common logarithm of lead concentration), there were no dose-response relationships in the analysis using quintiles of lead concentrations. Using a large-scale data set, the present study demonstrated no convincing evidence for an inverse association between levels of prenatal blood lead and neurodevelopment in early childhood. Longitudinal measurements of prenatal and postnatal lead levels are needed to understand the relationship between lead exposure and neurocognitive development.


Assuntos
Chumbo , Efeitos Tardios da Exposição Pré-Natal , Criança , Pré-Escolar , Feminino , Sangue Fetal , Humanos , Recém-Nascido , Japão/epidemiologia , Chumbo/toxicidade , Gravidez , Estudos Prospectivos
18.
Int J Mol Sci ; 23(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36076969

RESUMO

Lead (Pb) is an important raw material for modern industrial production, they enter the aquatic environment in several ways and cause serious harm to aquatic ecosystems. Lead ions (Pb2+) are highly toxic and can accumulate continuously in organisms. In addition to causing biological deaths, it can also cause neurological damage in vertebrates. Our experiment found that Pb2+ caused decreased survival, delayed hatching, decreased frequency of voluntary movements at 24 hpf, increased heart rate at 48 hpf and increased malformation rate in zebrafish embryos. Among them, the morphology of spinal malformations varied, with 0.4 mg/L Pb2+ causing a dorsal bending of the spine of 72 hpf zebrafish and a ventral bending in 120 hpf zebrafish. It was detected that spinal malformations were mainly caused by Pb2+-induced endoplasmic reticulum stress and apoptosis. The genetic changes in somatic segment development which disrupted developmental polarity as well as osteogenesis, resulting in uneven myotomal development. In contrast, calcium ions can rescue the series of responses induced by lead exposure and reduce the occurrence of spinal curvature. This article proposes new findings of lead pollution toxicity in zebrafish.


Assuntos
Curvaturas da Coluna Vertebral , Poluentes Químicos da Água , Animais , Ecossistema , Embrião não Mamífero/anormalidades , Desenvolvimento Embrionário/genética , Chumbo/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética
19.
Int J Mol Sci ; 23(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36077079

RESUMO

In the present study, nanocomposites having hierarchical nanoflowers (HNFs) -like morphology were synthesized by ultra-sonication approach. HNFs were ternary composite of MgFe2O4 and bentonite with boron-, phosphorous- co-doped graphene oxide (BPGO). The HNFs were fully characterized using different analytical tools viz. X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersion spectroscopy, transmission electron microscopy, X-ray diffraction, vibrating sample magnetometry and Mössbauer analysis. Transmission electron micrographs showed that chiffon-like BPGO nanosheets were wrapped on the MgFe2O4-bentonite surface, resulting in a porous flower-like morphology. The red-shift in XPS binding energies of HNFs as compared to MgFe2O4-bentoniteand BPGO revealed the presence of strong interactions between the two materials. Box-Behnken statistical methodology was employed to optimize adsorptive and photocatalytic parameters using Pb(II) and malathion as model pollutants, respectively. HNFs exhibited excellent adsorption ability for Pb(II) ions, with the Langmuir adsorption capacity of 654 mg g-1 at optimized pH 6.0 and 96% photocatalytic degradation of malathion at pH 9.0 as compared to MgFe2O4-bentonite and BPGO. Results obtained in this study clearly indicate that HNFs are promising nanocomposite for the removal of inorganic and organic contaminants from the aqueous solutions.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Adsorção , Bentonita/química , Grafite , Cinética , Chumbo , Malation , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química
20.
Int J Mol Sci ; 23(17)2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36077126

RESUMO

Sustainable agriculture is increasingly being put in danger by environmental contamination with dangerous heavy metals (HMs), especially lead (Pb). Plants have developed a sophisticated mechanism for nitric oxide (NO) production and signaling to regulate hazardous effects of abiotic factors, including HMs. In the current study, we investigated the role of exogenously applied sodium nitroprusside (SNP, a nitric oxide (NO) donor) in ameliorating the toxic effects of lead (Pb) on rice. For this purpose, plants were subjected to 1.2 mM Pb alone and in combination with 100 µM SNP. We found that under 1.2 mM Pb stress conditions, the accumulation of oxidative stress markers, including hydrogen peroxide (H2O2) (37%), superoxide anion (O2-) (28%), malondialdehyde (MDA) (33%), and electrolyte leakage (EL) (34%), was significantly reduced via the application of 100 µM SNP. On the other hand, under the said stress of Pb, the activity of the reactive oxygen species (ROS) scavengers such as polyphenol oxidase (PPO) (60%), peroxidase (POD) (28%), catalase (CAT) (26%), superoxide dismutase (SOD) (42%), and ascorbate peroxidase (APX) (58%) was significantly increased via the application of 100 µM SNP. In addition, the application of 100 µM SNP rescued agronomic traits such as plant height (24%), number of tillers per plant (40%), and visible green pigments (44%) when the plants were exposed to 1.2 mM Pb stress. Furthermore, after exposure to 1.2 mM Pb stress, the expression of the heavy-metal stress-related genes OsPCS1 (44%), OsPCS2 (74%), OsMTP1 (83%), OsMTP5 (53%), OsMT-I-1a (31%), and OsMT-I-1b (24%) was significantly enhanced via the application of 100 µM SNP. Overall, our research evaluates that exogenously applied 100 mM SNP protects rice plants from the oxidative damage brought on by 1.2 mM Pb stress by lowering oxidative stress markers, enhancing the antioxidant system and the transcript accumulation of HMs stress-related genes.


Assuntos
Metais Pesados , Oryza , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Peróxido de Hidrogênio/metabolismo , Chumbo/farmacologia , Metais Pesados/metabolismo , Óxido Nítrico/metabolismo , Nitroprussiato/farmacologia , Oryza/metabolismo , Estresse Oxidativo , Plântula/metabolismo , Superóxido Dismutase/metabolismo
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