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1.
Environ Monit Assess ; 193(5): 245, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33821384

RESUMEN

Studies to assess variability factors of heavy metals in soils are essential to understand their behavior in the environment and for the assessment of contaminated areas. In this context, this research aimed to study the factors that influence the variability of heavy metal levels and their bioavailability in pasture areas in the Alturas de Nazareno region, Mayabeque, Cuba, as well as the transfer to plants. Forty-five points were distributed in a natural pasture and at two depths (0-20 and 20-40 cm) as a function of relief and soil type. Pseudo-total heavy metal contents were determined according to method 3051A of USEPA, geochemical fractionation according to the Community Bureau of Reference method, and plant digestion according to method 3052 of USEPA. Soil samples were separated into two groups, according to cluster analysis. The type of soil associated with the pH and Ca attributes were the factors that most influenced the variability of the total and bioavailable levels of metals in natural pasture soils in the region of Alturas de Nazareno. Group 1 showed the lowest heavy metal contents and the highest pH and calcium values, which were predominantly associated with carbonate soils. Group 2 had the highest contents of heavy metals and Fe, corresponding mainly to the soil Ferralítico Rojo. The concentration of metals in plants was directly related to their bioavailable content in the soil, where G2 represents the group with the highest risk of transferring metals to the food chain.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Cuba , Monitoreo del Ambiente , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisis
2.
Environ Monit Assess ; 193(5): 256, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33835289

RESUMEN

Naturally elevated contents of copper (Cu) and nickel (Ni) are found in soils worldwide, and their potential toxicity is better understood when geochemical reactive fractions are identified and monitored. Thus, this study aimed to assess the bioavailability of Cu and Ni and estimate environmental risks in naturally metal-enriched soils of Carajás Mining Province, Eastern Amazon, Brazil. For that, 58 surficial soil samples were analyzed for their extractable contents of Cu and Ni by Mehlich 1. Next, 13 soil samples were selected for additional single and sequential extractions, for the determination of metal content in the shoots of grasses naturally growing in these soils and for calculating the risk assessment code. Despite the naturally high total concentrations, the contents of easily available Cu and Ni are a minor fraction of total concentrations (up to 10.15%), and the reducible oxide and residual pools hold the major proportion of total content of metals. This contributed to low bioavailability, low environmental risk, and also to low concentrations of these metals on grasses collected in the field. Soil organic matter, Fe2O3, Al2O3 and clay content have a dominant role in metals retention on studied soils. Our findings on the bioavailability of Cu and Ni in a region of great economic relevance for Brazil are important not only for predicting the elements' behavior in the soil-plant system but also for refining risk assessments and to provide useful data for environmental quality monitoring.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Disponibilidad Biológica , Brasil , Cobre/análisis , Monitoreo del Ambiente , Metales Pesados/análisis , Níquel , Suelo , Contaminantes del Suelo/análisis
3.
Environ Pollut ; 276: 116532, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33676149

RESUMEN

Wastewater reclamation and reuse for agriculture have attracted a great deal of interest, due to water stress caused by rapid increase in human population and agricultural water demand as well as climate change. However, the application of treated wastewater for irrigation can lead to the accumulation of pharmaceuticals and personal care products (PPCPs) in the agricultural crops, grazing animals, and consequently to human dietary exposure. In this study, a model was developed to simulate the fate of five PPCPs; triclosan (TCS), carbamazepine (CBZ), naproxen (NPX), gemfibrozil (GFB), and fluoxetine (FXT) during wastewater reuse for agriculture, and potential human dietary exposure and health risk. In a reclaimed wastewater-irrigated grazing farm growing alfalfa, it took 100-535 days for PPCPs to achieve the steady-state concentrations of 1.43 × 10-6, 4.73 × 10-5, 1.17 × 10-6, 1.53 × 10-5, and 7.38 × 10-6 mg/kg for TCS, CBZ, NPX, GFB, and FXT in soils, respectively. The accumulated concentration of PPCPs in the plant (alfalfa) and grazing animals (beef) ranged 2.86 × 10-7- 4.02 × 10-3 and 4.39 × 10-15- 6.27 × 10-7 mg/kg, respectively. Human dietary exposure to these compounds through beef consumption was calculated to be 1.67 × 10-18- 1.74 × 10-10 mg/kg bodyweight/d, much lower than the acceptable daily intake (ADI). Similar results were obtained for a 'typical' reclaimed wastewater irrigated farm based on the typical setup using our model. Screening analysis showed that PPCPs with relatively high LogD value and lower ratios of degradation rate (in soils) to plant uptake have a greater potential to be transferred to humans and cause potential health risks. We established a modeling method for evaluating the fate and human health effects of PPCPs in reclaimed wastewater reuse for the agricultural system and developed an index for screening PPCPs with high potential to accumulate in agricultural products. The model and findings are valuable for managing water reuse for irrigation and mitigating the harmful effects of PPCPs.


Asunto(s)
Cosméticos , Preparaciones Farmacéuticas , Contaminantes del Suelo , Contaminantes Químicos del Agua , Riego Agrícola , Agricultura , Humanos , Contaminantes del Suelo/análisis , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua/análisis
4.
J Environ Manage ; 286: 112227, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33647673

RESUMEN

Mining activity and abandoned mine land are one of the major sources of heavy metal pollution. Thus, ecological rehabilitation of abandoned mine lands is crucial to control heavy metal pollution. This research aims to explore the influencing factors and effects of different vegetation on copper (Cu) accumulation and soil amelioration. In this study, the abandoned land of Tongguanshan Cu mine in Tongling city, Anhui province, China, was chosen as the test area, and nine sampling points were established. Samples of soil and plants were collected from each plot, and the impacts of Cu pollution on soil enzymes and other features were analyzed, as well as the correlation between Cu accumulation of different plants and soil properties. The results showed that Cu content of soil in the Tongguanshan area varied greatly with the depth of the soil profile. Moreover, Cu in the soil can inhibit soil enzyme activities; and the correlation coefficients of total soil Cu with urease and catalase were -0.83 and -0.73, respectively. Clearly, the accumulation of Cu in plants was positively correlated with Cu content in soil. It was found that Pueraria lobata had the best remediation effect on soil Cu pollution in a short period of time. Hence the preliminary tests clearly indicate that phytoremediation in abandoned mine lands can not only reduce heavy metal pollution, but also enhance soil nutrition and enzyme activity, helping to ameliorate degraded land and promote regional socioeconomic sustainable development.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , China , Cobre , Monitoreo del Ambiente , Metales Pesados/análisis , Minería , Suelo , Contaminantes del Suelo/análisis
5.
Ecotoxicol Environ Saf ; 214: 112049, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33647852

RESUMEN

The disposal of untreated sanitary sewage in the soil has several consequences for human health and leads to environmental risks; thus, it is necessary investigating, monitoring and remediating the affected sites. The aims of the current study are to evaluate ecotoxicological effects on Eisenia andrei earthworms exposed to soil subjected to sources of sanitary sewage discharge and to investigate whether prevention values established by the Brazilian legislation for soil quality, associated with the incidence of chemical substances in it, are satisfactory enough to assure the necessary quality for different organisms. Earthworms' behavior, reproduction, acetylcholinesterase activity, catalase, superoxide dismutase and malondialdehyde levels were evaluated. The reproduction and behavior of earthworms exposed to sanitary sewage were adversely affected. Increased superoxide dismutase and catalase activity acted as antioxidant defense mechanism. Significantly increased lipid peroxidation levels and acetylcholinesterase activity inhibition have indicated lipid peroxidation in cell membrane and neurotransmission changes, respectively. Results have confirmed that sanitary sewage induced oxidative stress in earthworms. In addition, based on biochemical data analysis, the integrated biomarker response (IBR) has evidenced different toxicity levels in earthworms between the investigated points. Finally, results have indicated that effluents released into the soil, without proper treatment, lead to contaminant accumulation due to soil saturation and it can hinder different processes and biological development taking place in the soil. In addition, the current study has shown that physical-chemical analyses alone are not enough to assess soil quality, since it is also requires adopting an ecotoxicological approach. Brazilian legislation focused on soil quality must be revised and new guiding values must be proposed.


Asunto(s)
Oligoquetos/fisiología , Contaminantes del Suelo/análisis , Animales , Antioxidantes/metabolismo , Brasil , Catalasa/metabolismo , Ecotoxicología , Contaminación Ambiental/análisis , Humanos , Malondialdehído/metabolismo , Oligoquetos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Aguas del Alcantarillado , Suelo/química , Superóxido Dismutasa/metabolismo
6.
J Environ Manage ; 286: 112211, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33667819

RESUMEN

Urban community gardeners employ a range of best practices that limit crop contamination by toxicants like lead (Pb). While Pb root uptake is generally low, the relative significance of various Pb deposition processes and the effectiveness of best practices in reducing these processes have not been sufficiently characterized. This study compared leafy lettuce (Lactuca sativa) grown in high Pb (1150 mg/kg) and low Pb (90 mg/kg) soils, under three different soil cover conditions: 1) bare soil, 2) mulch cover to limit splash, and 3) mulch cover under hoophouses to limit splash and air deposition, in a New York City (NYC) community garden and a rural site in Ithaca, New York (NY). The lettuces were further compared to greenhouse (Ithaca) and supermarket (NYC) samples. Atmospheric deposition was monitored by passive trap collection through funnel samplers. Results show that in low Pb soils, splash and atmospheric deposition accounted for 84 and 78% of lettuce Pb in NYC and Ithaca, respectively. In high Pb soils, splash and atmospheric deposition accounted for 88 and 93% of Pb on lettuces, with splash being the dominant mechanism. Soil covers were shown to be effective at significantly (p < 0.05) reducing lettuce Pb contamination, and mulching is strongly recommended as a best practice.


Asunto(s)
Contaminantes del Suelo , Suelo , Plomo , Lechuga , Ciudad de Nueva York , Contaminantes del Suelo/análisis
7.
Sci Total Environ ; 772: 145554, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-33770853

RESUMEN

To understand the effect mechanisms of iron plaque and fatty acids on the migration of PBDEs from soil to rice (Oryza sativa), pot experiments were conducted in the soil spiked with decabromodiphenyl ether (BDE-209) under the conditions of tourmaline and nano-goethite Fenton-like treatments. The results showed that iron mineral Fenton-like oxidation could effectively remove BDE-209 from rhizosphere soil, the highest removal rate obtained 89.29% with the addition of 0.4 mmol/L H2O2 and 8 g nano-goethite (G + 3H group). Iron mineral Fenton-like oxidation could produce iron plaque (IP) on rice roots and accumulate a part of contaminants on the surface of IP, further weakening BDE-209 uptake in the plants. Additionally, the occurrence of fatty acid variation induced by BDE-209 stress, iron mineral Fenton-like oxidation at high concentrations of H2O2 with 0.4 mmol/L affected the distribution of fatty acids in plant tissues, especially for C18:0 fatty acid. While the IP on rice roots prevented the BDE-209 into plant, it was also closely related to the distribution of fatty acids in rice, altering BDE-209 accumulation in the rice. To safely use the iron mineral Fenton-like oxidation in the agricultural soil remediation, the safety of plant cells treated by mineral Fenton-like oxidation was evaluated using the transmission electron microscopy (TEM) and enzyme activity determination, which indicated that iron mineral Fenton-like oxidation would destroy the inner structures of plant cells, especially for G + 3H group.


Asunto(s)
Oryza , Contaminantes del Suelo , Ácidos Grasos , Éteres Difenilos Halogenados/análisis , Peróxido de Hidrógeno , Hierro/análisis , Minerales , Raíces de Plantas/química , Suelo , Contaminantes del Suelo/análisis
8.
Sci Total Environ ; 772: 145029, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-33770863

RESUMEN

Enhanced electrokinetic remediation (EKR) allows the rapid remediation of heavy metal-contaminated clay, but the impacts of this process on soil micro-ecology have rarely been evaluated. In this study, nitric acid, acetic acid, and EDTA were applied for enhancement of EKR and the effects on Cd removal, soil enzyme activity, and soil bacterial communities (SBCs) were determined. Nitric acid and acetic acid allowed 93.2% and 91.8% Cd removal, respectively, and EDTA treatment resulted in 40.4% removal due to the formation of negatively charged EDTA-Cd complexes, resulting in opposing directions of Cd electromigration and electroosmosis flow and slow electromigration rate caused by low voltage drop. Activities of soil beta-glucosidase, acid phosphatase, and urease, were all reduced by enhanced EKR treatment, especially nitric acid treatment, by 46.2%, 58.8% and 57.7%, respectively. The SBCs were analyzed by high-throughput sequencing and revealed significantly increased diversity for acetic acid treatment, no effect for EDTA treatment, and reduced diversity for nitric acid treatment. Compared with nitric acid and EDTA, acetic acid treatment enhanced EKR for higher Cd removal and improved biodiversity.


Asunto(s)
Restauración y Remediación Ambiental , Contaminantes del Suelo , Ácido Acético , Cadmio , Arcilla , Ácido Edético , Ácido Nítrico , Suelo , Contaminantes del Suelo/análisis
9.
Environ Monit Assess ; 193(4): 230, 2021 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-33772647

RESUMEN

Vegetables are essential for a healthy diet in humans. However, vegetables can carry harmful metal(loid) contaminants such as As, Cd and Pb which are deleterious to health in the long term. It has been postulated that long-term heavy metal(loid) exposure by vegetable consumption is associated with chronic kidney disease of unknown aetiology (CKDu) that prevails in North Central Province of Sri Lanka. We performed a human health risk assessment to identify if there is any link between heavy metal(loid) exposure from vegetable consumption and the prevalence of CKDu. The study includes a survey of food consumption in CKDu-impacted areas and determination of the heavy metal(loid) contents of market vegetables. We found that Solanum tuberosum (potato) and Momordica charantia (bitter gourd) accumulated Pb to a greater extent than other vegetables and exceeded the permissible concentration for foodstuffs. The Cd content of Solanum melongena (Brinjal) also exceeded permissible levels. However, the As content was below permissible levels for all the vegetables tested. The weekly total heavy metal(loid) intake of Cd, As and Pb in vegetables in CKDu-impacted areas was lower than permissible limits. The consumption of an average amount of vegetables does not pose a chronic health risk to the consumers. There was no evidence of a link between the consumption of heavy metal(loid)s in vegetables and CKDu. Since, few vegetables showed marked heavy metal(loid) accumulation, periodical monitoring of heavy metal(loid) concentrations in vegetables will be beneficial for avoidance of future possible health risks.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis , Sri Lanka , Verduras
10.
Environ Monit Assess ; 193(4): 232, 2021 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-33772660

RESUMEN

Soil and mine tailings are unreceptive to plant growth representing an imminent threat to the environment and resource sustainability. Using indigenous plants and their associated rhizobacteria to restore mining sites would be an eco-friendly solution to mitigate soil-metal toxicity. Soil prospection from Draa Sfar and Kettara mining sites in Morocco was carried out during different seasons for native plant sampling and rhizobacteria screening. The sites have been colonized by fifteen tolerant plant species having different capacities to accumulate Cu, Zn, and P in their shoots/root systems. In Draa Sfar mine, Suaeda vera J.F. Gmel., Sarcocornia fruticosa (L.) A.J. Scott., and Frankenia corymbosa Desf. accumulated mainly Cu (more than 90 mg kg-1), Atriplex halimus L. accumulated Zn (mg kg-1), and Frankenia corymbosa Desf. accumulated Pb (14 mg kg-1). As for Kettara mine, Aizoon canariense L. mainly accumulated Zn (270 mg kg-1), whereas Forsskalea tenacissima L. was the best shoot Cu accumulator with up to 50 mg kg-1, whereas Cu accumulation in roots was 21 mg kg-1. The bacterial screening revealed the strains' abilities to tolerate heavy metals up to 50 mg kg-1 Cu, 250 mg kg-1 Pb, and 150 mg kg-1 Zn. Isolated strains belonged mainly to Bacillaceae (73.33%) and Pseudomonadaceae (10%) and expressed different plant growth-promoting traits, alongside their antifungal activity. Results from this study will provide an insight into the ability of native plants and their associated rhizobacteria to serve as a basis for remediation-restoration strategies.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Bacterias , Biodegradación Ambiental , Monitoreo del Ambiente , Metales Pesados/análisis , Marruecos , Raíces de Plantas/química , Suelo , Contaminantes del Suelo/análisis
11.
Ecotoxicol Environ Saf ; 214: 112070, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33652361

RESUMEN

In line with sustainable development principles and in order to combat climate change, which contributes to progressive soil depletion, various solutions are being sought to use treated sewage sludge as a soil amendment to improve soil quality and enrich arable soils with adequate amounts of biogenic compounds. This review article focuses on the effects of the agricultural use of biosolids on the environment. The article reviews the existing knowledge on selected emerging contaminants in treated sewage sludge and describes the impact of these pollutants on the environment and living organisms based on 183 publications selected from over 16,000 papers on related topics published over the last ten years. This study deals not only with chemical contaminants but also genetic determinants of resistance to these compounds. Current research has questioned the agricultural use of biosolids due to the presence of mutual interactions between antibiotics, heavy metals, the genetic determinants of resistance (antibiotic resistance genes - ARGs and heavy metal resistance genes - HMRGs) and non-steroidal anti-inflammatory drugs as well as the risks associated with their transfer to the environment. This study emphasizes the need for more extensive legal regulations that account for other pollutants of environmental concern (PEC), particularly in countries where sewage sludge is applied in agriculture most extensively. Future research should focus on more effective methods of eliminating PEC from sewage sludge, especially from the sludge that is used to fertilize agricultural land, because even small amounts of these micropollutants can have serious implications for the health and life of humans and animals.


Asunto(s)
Agricultura , Aguas del Alcantarillado/química , Contaminantes del Suelo/análisis , Eliminación de Residuos Líquidos/métodos , Animales , Antibacterianos , Productos Agrícolas , Farmacorresistencia Microbiana/genética , Contaminantes Ambientales , Humanos , Metales Pesados/análisis , Suelo/química
12.
Ecotoxicol Environ Saf ; 214: 112097, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33667736

RESUMEN

Plant ZIP genes represent an important transporter family and may be involved in cadmium (Cd) accumulation and Cd resistance. In order to explore the function of SmZIP isolated from Salix matsudana, the roles of SmZIP in Cd tolerance, uptake, translocation, and distribution were determined in the present investigation. The transgenic SmZIP tobacco was found to respond to external Cd stress differently from WT tobacco by exhibiting a higher growth rate and more vigorous phenotype. The overexpression of SmZIP in tobacco resulted in the reduction of Cd stress-induced phytotoxic effects. Compared to WT tobacco, the Cd content of the root, stem, and leaf in the transgenic tobacco increased, and the zinc, iron, copper, and manganese contents also increased. The assimilation factor, translocation factor and bioconcentration factor of Cd were improved. The scanning electron microscopy and energy dispersive X-ray analysis results of the root maturation zone exposed to Cd for 24 h showed that Cd was transferred through the root epidermis, cortex, and vascular cylinder and migrated to the aboveground parts via the vascular cylinder, resulting in the transgenic tobacco accumulating more Cd than the WT plants. Based on the transverse section of the leaf main vein and leaf blade, Cd was transported through the vascular tissues to the leaves and accumulated more greatly in the leaf epidermis, but less in the leaf mesophyll cells, following the overexpression of SmZIP to reduce the photosynthetic toxicity. The overexpression of SmZIP resulted in the redistribution of Cd at the subcellular level, a decrease in the percentage of Cd in the cell wall, and an increase of the Cd in the soluble fraction in both the roots and leaves. It also changed the percentage composition of different Cd chemical forms by elevating the proportion of Cd extracted using 2% HAc and 0.6 mol/L HCl, but lowering that of the Cd extracted using 1 mol/L NaCl in both the leaves and roots under 10 and 100 µmol/L Cd stress for 28 d. The results implied that SmZIP played important roles in advancing Cd uptake, accumulation, and translocation, as well as in enhancing Cd resistance by altering the Cd subcellular distribution and chemical forms in the transgenic tobacco. The study will be useful for future phytoremediation applications to clean up Cd-contaminated soil.


Asunto(s)
Cadmio/toxicidad , Contaminantes del Suelo/toxicidad , Tabaco/fisiología , Biodegradación Ambiental , Cadmio/análisis , Pared Celular/química , Genes de Plantas , Hojas de la Planta/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Salix , Contaminantes del Suelo/análisis , Tabaco/efectos de los fármacos , Zinc/análisis
13.
Huan Jing Ke Xue ; 42(4): 1979-1988, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742833

RESUMEN

In order to reveal the impact of the application of biogas slurry instead of chemical nitrogen fertilizer on the environmental risk of heavy metals in the soil by returning straw to the field, four treatments, without biogas slurry and without straw applications (CK), biogas slurry application without straw (B), straw application without biogas slurry (S), and biogas slurry combined with straw applications (BS), were applied in a typical coastal reclaimed farmland (rice-wheat rotation) in Jiangsu province. The migration and morphological characteristics of Cu, Zn, Cd, and Pb in different soil layers were observed, and the potential environmental risks were estimated. The results showed that:① The total amounts of Zn and Pb in the surface soils (0-20 cm) in the rice and wheat fields under the BS treatment decreased significantly (P<0.05). The four heavy metals in the paddy soils migrated 6%-11% from the surface to the middle and lower layers (20-60 cm), and Cu, Cd, and Pb in the wheat soils migrate down from the surface by 25% to 33%. This indicated that the combined use of biogas slurry and straw accelerates the vertical downward movement of heavy metals in the surface soil. ② Under the BS treatment, the contents of the weak acid extraction of Cu in the surface soil of the paddy field decreased by 8.8%, and the residual state of Zn, Cd, and Pb decreased by 7.0% to 14.2%. This revealed that Cu was passivated, but Zn, Cd, and Pb tended to be activated. In comparison, the reduction in Cu residues in wheat field surface soil was 2.8 times that of the weak acid extraction, indicating that Cu was activated. Furthermore, the residue state of Cd increased, the weak acid extraction state of Pb decreased, and Cd and Pb were passivated. ③ The ecological risk assessment of heavy metals showed that there is no ecological risk in the soils under the BS treatment, and the risk indices were significantly lower than those of the B and S treatments (P<0.05). Therefore, the combined use of biogas slurry and straw helps to significantly reduce the risk of heavy metal pollution in the soils in the coastal reclamation areas.


Asunto(s)
Metales Pesados , Oryza , Contaminantes del Suelo , Biocombustibles , China , Monitoreo del Ambiente , Metales Pesados/análisis , Rotación , Suelo , Contaminantes del Suelo/análisis , Triticum
14.
Huan Jing Ke Xue ; 42(4): 2003-2015, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742835

RESUMEN

In order to evaluate the potential ecological risk of heavy metals in the soil-crop system in the Xiong'an New District, the heavy metal contents and forms in wheat seed and root soil samples are analyzed, and the comprehensive pollution index (IPIN), potential ecological risk index (RI), bio-enrichment coefficient (BFC), risk assessment code (RAC), principal component analysis, and correlation analysis are used to assess the potential ecological risk of heavy metals and analyze their sources. The results indicate that the average content of Cd, Cu, Pb, and Zn in the root soil is significantly higher than the soil background value in Hebei province. The IPIN ranges from 0.2 to 5.18, 94.83% of the soil samples are in the safe and pollution-free grade, and the potential ecological risks of heavy metal are slight and moderate, accounting for 64.66% and 30.17%, respectively. Cd has the greatest potential ecological harm, followed by Hg, Cr, Ni, and Zn. All the heavy metal elements besides Cd in the root soil are dominated by the residual form, which accounts for 60%, and the bioactive form (ion-exchange and water-soluble state) of Cd accounts for 33.43%, indicating relatively high bio-availability. The risk assessment code can be ranked as Cd > Ni > Hg > As > Cu > Cr > Zn > Pb, and the risk of Cd is moderate, while other elements are of low or no risk. The leading potential source of heavy metals is human activity combined with the geological background. The migration and enrichment capability of the wheat seeds is in order from strong to weak of Zn > Cu > Cd > Hg > As > Ni > Pb > Cr, and the biological effective components of As, Cd, Pb, and Zn plays an substantial role in promoting the absorption of heavy metals. The content of heavy metals in the wheat seeds has a negative correlation with the soil pH, and the physical and chemical indices, such as OM and CEC, has bi-directional influence on the biological effective state of the heavy metals.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , China , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
15.
Huan Jing Ke Xue ; 42(4): 2016-2023, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742836

RESUMEN

The cadmium (Cd) accumulation characteristics of seven rice varieties (Ningliangyou 1, Y Liangyou 1, Shenliangyou, Tailiangyou, Yuejingsimiao, Youzhanbahao, and Huang Huazhan) were studied by pot-culture experiments in two paddy soils (Maling, Yunbiao) with different high geological backgrounds, and the possible impacting factors were explored. The results indicated that:① The grain Cd contents of the seven rice varieties grown in the two soils did not exceed the national food safety standard (GB 2762-2017), and the grain Cd content of Shengliangyou was the lowest; ② The grain Cd content of the seven rice varieties planted in the soil of Maling was higher than those of Yunbiao; ③ The redundancy analysis revealed that the accumulation of Cd in grains was influenced by the plant height, surface area of root, total cadmium in the soil, and EC and Eh of the soil during the heading stage. The correlation analysis indicated that the leading impacting factor of the grain Cd accumulation varied. In the Maling soil, the grain Cd content was primarily related to the rice root length, while it was related to the aboveground rice biomass in the Yunbiao soil.


Asunto(s)
Oryza , Contaminantes del Suelo , Cadmio/análisis , Grano Comestible/química , Suelo , Contaminantes del Suelo/análisis
16.
Huan Jing Ke Xue ; 42(4): 2024-2030, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742837

RESUMEN

This study explored the discrepancy in the detoxification effects of different exogenous selenium (Se) species in cadmium (Cd)-contaminated soil to provide a scientific basis for the control of Cd pollution in the soil and the safe production of crops. A pot experiment was conducted to compare the effects of different concentrations (0, 0.5, 1.0, and 2.5 mg·kg-1) of selenite and selenate on the growth (root length, shoot height, biomass, and photosynthetic parameters), uptake, and translocation of Cd on pak choi in Cd-contaminated soil. The results indicated that the detoxification effect of a low Se concentration (≤1.0 mg·kg-1) treatment on Cd was better than that with a high Se concentration (2.5 mg·kg-1) treatment, and the selenite treatment demonstrated a greater detoxification effect on Cd than the corresponding selenate treatment. Meanwhile, the application of low-concentration selenite and selenate both increased the SPAD value, Pn, Gs, Ci, biomass, and shoot length of the pak choi, and the 1.0 mg·kg-1 selenite treatment had the most significant (P<0.05) effect (except Ci). Nevertheless, the photosynthetic parameters of the pak choi under the high-concentration Se were significantly lower than those under the low Se concentration treatment (except Tr, P<0.05). Compared with the treatment without Se (control), the uptake of Cd in the pak choi was reduced under different Se treatments. Compared with the control, the Cd concentration in the shoots of the pak choi treated with 1.0 mg·kg-1 of selenite and selenate decreased by 40.0% and 20.5% (P<0.05), respectively. In addition, the translocation of Cd from the root to the shoot was significantly reduced under the 0.5 mg·kg-1 selenate treatment, while the high-concentration treatments of either exogenous Se promoted the translocation of Cd. Overall, applying the appropriate amount of exogenous Se could promote the photosynthesis and biomass of pak choi, and reduce the accumulation of Cd in pak choi. Therefore, the 1.0 mg·kg-1 selenite treatment is recommended for the control and safe utilization of Cd in Cd-contaminated soil.


Asunto(s)
Brassica , Selenio , Contaminantes del Suelo , Cadmio/toxicidad , Ácido Selénico , Suelo , Contaminantes del Suelo/análisis
17.
Huan Jing Ke Xue ; 42(4): 2031-2039, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742838

RESUMEN

The Cd bioaccumulation factor (BCF) of crops is affected by many aspects. In order to clarify the differences in the Cd bioaccumulation factor characteristics of different crops under field conditions and the influence of soil properties, point-to-point samples of soil and crop grains were collected during crop harvesting on plots with varying pollution levels in the primary production areas of rice, wheat, and maize in China. The characteristics of the Cd bioaccumulation factors of rice, wheat, summer maize, and spring maize and the effects of soil properties on the Cd bioaccumulation factors of different crops were studied, and the quantitative relationship between the Cd bioaccumulation factors and soil properties was established through multiple regression equations. The results revealed that the average BCF values of Cd in rice, wheat, summer maize, and spring maize were 0.915, 0.155, 0.113, and 0.102, respectively, with the Cd content in the field soil of 0.15-2.66 mg·kg-1. Rice is significantly higher than wheat and maize, and spring maize has the lowest Cd bioaccumulation factor. The Cd content in the soil is extremely negatively correlated with the BCF of wheat, summer maize, and spring maize. The relationship between soil organic matter (SOM) and the BCF of wheat and summer maize demonstrated a significant negative correlation. The soil pH and cation exchange capacity (CEC) also affect the BCF of crops. Introducing the soil Cd content, pH, SOM, CEC, and other factors, the Cd bioaccumulation factor prediction equations of rice, wheat, summer maize, and spring maize were established. The correlation coefficients of the BCF prediction equations for rice, wheat, summer maize, and spring maize are 0.423*, 0.796**, 0.826**, and 0.551**, respectively. The above models reached significant or extremely significant levels, which can better predict the BCF value of different crops under varying soil conditions.


Asunto(s)
Oryza , Contaminantes del Suelo , Bioacumulación , Cadmio/análisis , China , Suelo , Contaminantes del Suelo/análisis
18.
Huan Jing Ke Xue ; 42(4): 2047-2055, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742840

RESUMEN

A pot experiment was carried out to study the impacts of five organic materials (rape straw, broad bean stalk, peat, pig manure compost, and biochar) on the availability of arsenic (As) and cadmium (Cd) in soil, the amount of iron plaque on the root surface, as well as the uptake and translocation of As and Cd in rice grown in an As/Cd co-contaminated yellow paddy soil. The results indicated that the application of organic materials significantly increased the contents of the soil organic matter and the yield of rice. The application of broad bean stalk, peat, pig manure compost, and biochar remarkably increased the soil pH, while the application of rape straw exerted no significant influence. The addition of organic matter reduced the available Cd content by 34.77%-82.69%. However, the effects of organic materials on the availability of As varied with the organic materials. The soil-available As content was significantly increased by the application of pig manure compost and biochar, while it was significantly decreased by adding rape straw and peat. The application of organic materials increased As and Cd contents in the Fe plaques on rice root surface by 28.49%-94.86% and 17.73%-151.03%, respectively. It also reduced the As and Cd contents in brown rice by 27.04%-82.51% and 15.87%-79.45%, respectively. The largest decrease was observed in the biochar treatment. The application of organic materials also remarkably reduced the translocation efficiency of Cd from the root-stem-leaf-grain and that of As from the stem to grain. The correlation analysis revealed that the soil pH, available Cd, and Cd content in the Fe plaques are the major factors influencing the accumulation of Cd in the rice grain. Furthermore, the soil pH, soil organic matter, and As content in the Fe plaques are the major factors influencing the accumulation of As in the rice grain. Therefore, it has been concluded that organic materials could influence the uptake and translocation of As and Cd in rice through changing the soil pH, organic matter content, and As and Cd contents in the Fe plaques.


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Animales , Cadmio/análisis , Carbón Orgánico , Suelo , Contaminantes del Suelo/análisis , Porcinos
19.
Huan Jing Ke Xue ; 42(2): 900-908, 2021 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-33742885

RESUMEN

In order to fully explore the spatial distribution of soil heavy metal contaminants in farmland soil surrounding a typical industrial area in Dakuai town, Xinxiang city, Henan Province, the concentrations of As, Cd, Cr, Cu, Ni, Pb, and Zn in the surface soil and within the soil profile were determined and assessed. The principal components were also analyzed for source apportionment to provide a theoretical basis for the control and prevention of heavy metal pollution. According to the results, the soils in the study area are severely contaminated by Cd and Cu and moderated contaminated by As due to the battery manufacture and Cu (e.g., pipe and wire) processing. The concentrations of Cd, Cu, and As in soils were (2.56±1.23) mg·kg-1, (205.58±157.49) mg·kg-1, and (15.27±4.14) mg·kg-1, respectively, which exceeds standards by 100%, 89.44%, and 3.40%, respectively. Accounting for the influence of pollution sources, terrain, runoff erosion, and prevailing wind direction, all heavy metal concentrations were higher in the south direction, lower in the north direction. The concentrations of Cd and Cu in soil profile samples decreased with depth, with highest concentrations at the surface, indicating the strong effect of industrial activities. Arsenic concentrations varied little with soil depth due to its strong migration ability in alkaline soil, again suggesting an industrial source. Among them, the soil of study area was severely contaminated by Cd and Cu (Level 5). Cd poses a severe potential ecological risk (Level 5) and Cu poses a medium risk (Level 2) in the study soils, while other heavy metals show low potential ecological risk (Level 1). The order of the risk identified was Cd > Cu > Ni > As > Pb > Cr > Zn. In addition, the combined potential ecological risk of heavy metals in the target area is severe. The principal component analysis showed that the high As, Cd, and Cu contents are mainly derived from industrial areas. Therefore, it is urgent to remediate Cd and Cu soil contamination in this area and implement precautions to limit As contamination.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , China , Ciudades , Monitoreo del Ambiente , Granjas , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
20.
Huan Jing Ke Xue ; 42(2): 932-940, 2021 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-33742889

RESUMEN

Cadmium (Cd) is easily enriched in rice, resulting in an excessive Cd content in the grain, which seriously threatens human health. Manganese (Mn) is an essential element of plants. In a field experiment on Cd-contaminated acid soils, we investigated the effectiveness and mechanism of Mn in minimizing Cd accumulation in rice via foliar spraying using 0.1%, 0.3%, and 0.5% nano-MnO2 solutions at an early stage of heading. Compared with a control treatment, foliar spraying effectively reduced the Cd content of rice leaves, husks, and brown rice; increased the Mn content of all rice organs; but had no effect on rice yield. Foliar application of nano-MnO2 alleviated the plant stress induced by Cd by improving leaf photosynthesis, inhibiting lipid peroxidation, and increasing the content of the oxidative stress protein kinase. In addition, foliar application of nano-MnO2 limited the absorption of Cd by roots by increasing the content of iron-manganese plaque on the surfaces of rice roots and strengthening its adsorption/co-precipitation of Cd. Therefore, foliar application of nano-MnO2 during the early stages of rice heading is an effective measure to increase the Mn content and reduce the Cd content of brown rice.


Asunto(s)
Oryza , Contaminantes del Suelo , Cadmio/análisis , Cadmio/toxicidad , Grano Comestible/química , Humanos , Suelo , Contaminantes del Suelo/análisis
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