Heavy Metal Contamination in Soil and Health Risks

A special issue of Toxics (ISSN 2305-6304). This special issue belongs to the section "Metals and Radioactive Substances".

Deadline for manuscript submissions: closed (20 October 2022) | Viewed by 35439

Special Issue Editors


E-Mail Website
Guest Editor
Department of Energy Resources and Geosystem Engineering, College of Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea
Interests: heavy metals in soils; soil amendment; mining environment; rice and paddy soils; soil-plant relationship

E-Mail Website
Guest Editor
Environmental Land Management Department at WSP Australia, 28 Freshwater Pl, Southbank VIC 3006, Melbourne, Australia
Interests: soil contamination; heavy metal(loid)s; biosolids; site remediation; risk assessment

Special Issue Information

Dear Colleagues,

There are various sources of heavy metals in soils, including mining, industrial activities, waste disposal sites, even geological materials. Thus, heavy metal contaminated soil nowadays is receiving the utmost concern from researchers due to its undesirable effects and health risk in the environmental systems. Owing to the low degradability, chemical complexity, and toxicity of the metals, numerous studies have been undertaken, such as environmental surveys, physicochemical and biological analyses, and risk assessments. In addition, much effort has been made to solve the environmental problems of heavy metal contaminated soils. Among them, soil washing, stabilization/solidification, electro-kinetic, and soil amendment technologies were adapted to remove the metals in soils. Furthermore, human and ecological risk assessment of the metals in soils was also undertaken.

Therefore, this Special Issue will focus on highlighting timely research studies addressing the leading techniques related to survey, analysis, evaluation, and remediation of the metals in soils. Authors are invited and welcome to submit original research papers, reviews, and short communications.

Topics may include, but are not limited to, the following:

  1. Identify the sources of heavy metals in soils;
  2. Establish the analysis of heavy metals in soils;
  3. Evaluate the health risk assessment derived from heavy metal contaminated soils;
  4. Apply the remediation techniques of heavy metals in soils;
  5. Conduct all studies related to heavy metals in soils and health risk issues.

Prof. Dr. Myung Chae Jung
Dr. Zahra Derakhshan-Nejad
Guest Editors

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Keywords

  • investigation on heavy metals in soils
  • sources of heavy metals in soils
  • human and ecological risk assessment from contaminated soils
  • heavy metal remediation technology
  • soil, plant, and microbial community

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Published Papers (13 papers)

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Research

10 pages, 1707 KiB  
Article
Environmental Assessment of Friable Asbestos from Soil to Air Using the Releasable Asbestos Sampler (RAS)
by Puteri Tiara Maulida, Jeong Wook Kim and Myung Chae Jung
Toxics 2022, 10(12), 748; https://doi.org/10.3390/toxics10120748 - 1 Dec 2022
Cited by 1 | Viewed by 1736
Abstract
The objectives of this study are to examine the feasibility of the releasable asbestos sampler (RAS) equipment for laboratory tests as an alternative to activity-based sampling (ABS), and to apply the equipment controlled by wind velocity and water contents in the field to [...] Read more.
The objectives of this study are to examine the feasibility of the releasable asbestos sampler (RAS) equipment for laboratory tests as an alternative to activity-based sampling (ABS), and to apply the equipment controlled by wind velocity and water contents in the field to asbestos-contaminated soils. Two asbestos-contaminated mines (the Jecheon mine and the Jongmin-ri mine) were selected. At each mine, 21 surface soils (0~15 cm) were sampled, the asbestos concentrations were analyzed, and then three representative sites, containing 0.25%, 0.50%, and 0.75% of asbestos in soils, were chosen to evaluate the amount of releasable asbestos by the modified RAS with wind velocity and water contents. The results showed that the levels of releasable asbestos from soil to air increased with higher wind velocities and lower water content. In addition, the application of risk assessment of releasable asbestos in the soils as an alternative to the activity-based sampling (ABS) method was established at each site, and an estimation of the excess lifetime cancer risk (ELCR) was also calculated. According to the calculation, the estimated ELCR values did not exceed the threshold value (1 × 10−4) in the Jecheon mine for all the soils, while some samples from the Jongmin-ri mine exceeded the threshold value. Therefore, proper remediation work is needed to control friable asbestos from soils to air in the vicinity of the mines. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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8 pages, 873 KiB  
Article
Insight into the Burden of Malignant Respiratory Tumors and their Relationship with Smoking Rates and Lead Contamination in Mexico
by Oliver Mendoza-Cano, Efrén Murillo-Zamora, Ángeles Catalina Ochoa-Martínez, Valeria Argentina Mendoza-Olivo, Mónica Ríos-Silva, Xóchitl Trujillo, Miguel Huerta, Jaime Alberto Bricio-Barrios, Verónica Benites-Godínez, Irma González-Curiel, Rebeca Yasmín Pérez-Rodríguez, Nadia Azenet Pelallo-Martínez and Agustín Lugo-Radillo
Toxics 2022, 10(11), 708; https://doi.org/10.3390/toxics10110708 - 20 Nov 2022
Viewed by 2022
Abstract
We aimed to report the results from the Global Burden of Disease Study 2019 related to respiratory malignant tumors (tracheal, bronchial, and lung) in Mexico. We also evaluated the relationship between the burden of these neoplasms and the proportion of daily smokers and [...] Read more.
We aimed to report the results from the Global Burden of Disease Study 2019 related to respiratory malignant tumors (tracheal, bronchial, and lung) in Mexico. We also evaluated the relationship between the burden of these neoplasms and the proportion of daily smokers and total lead emissions in 2019. A cross-sectional analysis of ecological data was performed. The burden of these tumors was 152,189 disability-adjusted life-years (DALYs), and years of life lost (YLL) contributed to 99% of them. The highest DALYs rates (per 100,000) were observed in the states of Sinaloa, Chihuahua, Baja California Sur, Sonora, and Nayarit. We documented a linear relationship between the DALYs rates and the prevalence of daily smokers (β = 8.50, 95% CI 1.58–15.38) and the total lead emissions (tons/year: β = 4.04, 95% CI 0.07–8.01). If later replicated, our study would provide insight into the major relevance of regulating tobacco use and the activities associated with the production of lead dust and other hazardous contaminants. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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12 pages, 1542 KiB  
Article
Adsorption Characteristics of Dimethylated Arsenicals on Iron Oxide–Modified Rice Husk Biochar
by Sang-Gyu Yoon, Ihn-Sil Kwak, Hye-On Yoon and Jinsung An
Toxics 2022, 10(11), 703; https://doi.org/10.3390/toxics10110703 - 17 Nov 2022
Cited by 4 | Viewed by 1856
Abstract
In this study, the adsorption characteristics of dimethylated arsenicals to rice husk biochar (BC) and Fe/biochar composite (FeBC) were assessed through isothermal adsorption experiments and X-ray absorption spectroscopy analysis. The maximal adsorption capacities (qm) of inorganic arsenate, calculated using the Langmuir [...] Read more.
In this study, the adsorption characteristics of dimethylated arsenicals to rice husk biochar (BC) and Fe/biochar composite (FeBC) were assessed through isothermal adsorption experiments and X-ray absorption spectroscopy analysis. The maximal adsorption capacities (qm) of inorganic arsenate, calculated using the Langmuir isotherm equation, were 1.28 and 6.32 mg/g for BC and FeBC, respectively. Moreover, dimethylated arsenicals did not adsorb to BC at all, and in the case of FeBC, qm values of dimethylarsinic acid (DMA(V)), dimethylmonothioarsinic acid (DMMTA(V)), and dimethyldithioarsinic acid (DMDTA(V)) were calculated to be 7.08, 0.43, and 0.28 mg/g, respectively. This was due to the formation of iron oxide (i.e., two-line ferrihydrite) on the surface of BC. Linear combination fitting using As K-edge X-ray absorption near edge structure spectra confirmed that all chemical forms of dimethylated arsenicals adsorbed on the two-line ferrihydrite were DMA(V). Thus, FeBC could retain highly mobile and toxic arsenicals such as DMMTA(V) and DMDTA(V)) in the environment, and transform them into DMA(V) with relatively low toxicity. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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13 pages, 1652 KiB  
Article
Dynamic Adsorption Characteristics of Cr(VI) in Red-Mud Leachate onto a Red Clay Anti-Seepage Layer
by Yibo Zhang, Yue Yu, Hao Qin, Daoping Peng and Xing Chen
Toxics 2022, 10(10), 606; https://doi.org/10.3390/toxics10100606 - 12 Oct 2022
Cited by 3 | Viewed by 1847
Abstract
Red-mud leachate from tailings ponds contains Cr(VI), which can pollute groundwater via infiltration through anti-seepage layers. This paper investigates leachate from a red-mud tailings pond in southwest China and the red clay in the surrounding area to simulate the adsorption of Cr(VI) onto [...] Read more.
Red-mud leachate from tailings ponds contains Cr(VI), which can pollute groundwater via infiltration through anti-seepage layers. This paper investigates leachate from a red-mud tailings pond in southwest China and the red clay in the surrounding area to simulate the adsorption of Cr(VI) onto clay at different pHs, using geochemical equilibrium software (Visual MINTEQ). We also performed dynamic adsorption testing of Cr(VI) on a clay anti-seepage layer. The dynamic adsorption behaviors and patterns in the dynamic column were predicted using the Thomas and Yoon–Nelson models. Visual MINTEQ predicted that Cr(VI) adsorption in red-mud leachate onto clay was 69.91%, increasing gradually with pH, i.e., adsorption increased under alkaline conditions. Cr(VI) concentration in the effluent was measured using the permeability test through a flexible permeameter when the adsorption saturation time reached 146 days. At a low seepage rate, Cr(VI) adsorption onto the clay anti-seepage layer took longer. Saturation adsorption capacity, q0, and adsorption rate constant, Kth, were determined using the Thomas model; the Yoon–Nelson model was used to determine when the effluent Cr(VI) concentration reached 50% of the initial concentration. The results provide parameters for the design and pollution prediction of the clay anti-seepage layer of red-mud tailings ponds. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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17 pages, 2087 KiB  
Article
Uranium Concentrations in Private Wells of Potable Groundwater, Korea
by Woo-Chun Lee, Sang-Woo Lee, Ji-Hoon Jeon, Jong-Hwan Lee, Do-Hwan Jeong, Moon-Su Kim, Hyun-Koo Kim and Soon-Oh Kim
Toxics 2022, 10(9), 543; https://doi.org/10.3390/toxics10090543 - 18 Sep 2022
Cited by 2 | Viewed by 2003
Abstract
Uranium (U) is one of the typical naturally occurring radioactive elements enriched in groundwater through geological mechanisms, thereby bringing about adverse effects on human health. For this reason, some countries and the World Health Organization (WHO) regulate U with drinking water standards and [...] Read more.
Uranium (U) is one of the typical naturally occurring radioactive elements enriched in groundwater through geological mechanisms, thereby bringing about adverse effects on human health. For this reason, some countries and the World Health Organization (WHO) regulate U with drinking water standards and monitor its status in groundwater. In Korea, there have been continuous investigations to monitor and manage U in groundwater, but they have targeted only public groundwater wells. However, the features of private wells differ from public ones, particularly in regard to the well’s depth and diameter, affecting the U distribution in private wells. This study was initiated to investigate U concentrations in private groundwater wells for potable use, and the significant factors controlling them were also elucidated through statistical methods. The results obtained from the analyses of 7036 groundwater samples from private wells showed that the highest, average, and median values of U concentrations were 1450, 0.4, and 4.0 μg/L, respectively, and 2.1% of the wells had U concentrations exceeding the Korean and WHO standard (30 μg/L). In addition, the U concentrations were highest in areas of the Jurassic granite, followed by Quaternary alluvium and Precambrian metamorphic rocks. A more detailed investigation of the relationship between U concentration and geology revealed that the Jurassic porphyritic granite, mainly composed of Daebo granite, showed the highest U contents, which indicated that U might originate from uraninite (UO2) and coffinite (USiO4). Consequently, significant caution should be exercised when using the groundwater in these geological areas for potable use. The results of this study might be applied to establish relevant management plans to protect human health from the detrimental effect of U in groundwater. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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17 pages, 7835 KiB  
Article
Assessment of Soil-Heavy Metal Pollution and the Health Risks in a Mining Area from Southern Shaanxi Province, China
by Rui Chen, Lei Han, Zhao Liu, Yonghua Zhao, Risheng Li, Longfei Xia and Yamin Fan
Toxics 2022, 10(7), 385; https://doi.org/10.3390/toxics10070385 - 11 Jul 2022
Cited by 28 | Viewed by 3648
Abstract
Soil-heavy metal pollution in mining areas is one of the problems in the comprehensive treatment of soil environmental pollution. To explore the degree of soil-heavy metal pollution and the human health risk in mining areas, the contents of soil As, Cd, Cu, Cr, [...] Read more.
Soil-heavy metal pollution in mining areas is one of the problems in the comprehensive treatment of soil environmental pollution. To explore the degree of soil-heavy metal pollution and the human health risk in mining areas, the contents of soil As, Cd, Cu, Cr, Hg, Ni, Pb, and Cr(VI) in an abandoned gold mining area were determined. The geoaccumulation index (Igeo), single-factor pollution index (SPI), Nemerow comprehensive pollution index (NCPI), potential ecological risk index (PERI), and the human health risk assessment model were used to assess the pollution degree and the risk of soil-heavy metal pollution. Finally, the assessment results were used to provide remediation guidance. The results showed that (1) the average contents of As, Cd, Cr, Cu, Hg, and Ni in the mining area exceeded the background values of the soil elements. (2) The mining area was polluted by heavy metals to different degrees and had strong potential ecological hazards. (3) The total carcinogenic risk of heavy metals exceeded the health risk standard. The main components of pollution in the mining area were As, Cd, Cr, and Hg. Results from this study are expected to play a positive role in pollution treatment and the balance between humans and ecology. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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15 pages, 1017 KiB  
Article
Lead and Cadmium Bioaccumulation in Fresh Cow’s Milk in an Intermediate Area of the Central Andes of Peru and Risk to Human Health
by Doris Chirinos-Peinado, Jorge Castro-Bedriñana, Elva Ríos-Ríos, Gloria Mamani-Gamarra, Elías Quijada-Caro, Analí Huacho-Jurado and Wilfredo Nuñez-Rojas
Toxics 2022, 10(6), 317; https://doi.org/10.3390/toxics10060317 - 11 Jun 2022
Cited by 15 | Viewed by 3131
Abstract
The dairy basin of the Mantaro River located in the centre of Peru faces serious anthropogenic disturbances as it receives emissions and discharges from the metallurgical mining activity located in the headwaters of the basin and milk contaminated with lead (Pb) and cadmium [...] Read more.
The dairy basin of the Mantaro River located in the centre of Peru faces serious anthropogenic disturbances as it receives emissions and discharges from the metallurgical mining activity located in the headwaters of the basin and milk contaminated with lead (Pb) and cadmium (Cd) endangers the environmental and human health, especially children. To measure the concentrations of Pb and Cd in milk and the dangers of their consumption in the Peruvian population, 40 milk samples were collected and quantified by atomic absorption spectrometry. The mean concentration of Pb in milk was 15 ± 2.6 µg/kg, which represented 75% of the Maximum Limit (ML), and that of Cd was 505 ± 123 µg/kg, which exceeded the ML by more than 194 times. The estimated weekly intake of Pb for people aged 2–85 years was below the Provisional Tolerable Weekly Intake (PTWI) references, determining risk coefficients (CRD) < 1. Weekly Cd intake was much higher than the PTWIs and CRDs were between 14 and 34, indicating that consumers would experience carcinogenic health effects, with children being at higher risk than adults, therefore, milk from the area is not safe for consumption. Cd would be transferred mainly through the soil (water)-grass-milk pathway, due to its presence in irrigation water and in fertilizers that contain Cd. The main pathway for Pb entry would be air-soil (water)-milk grass, from the fine particles emitted into the air by the mining-metallurgical activity, developed approximately 90 km from the study area. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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15 pages, 2718 KiB  
Article
Use of Radioisotope Ratios of Lead for the Identification of Historical Sources of Soil Lead Contamination in Santa Ana, California
by Shahir Masri, Alana M. W. LeBrón, Michael D. Logue, Patricia Flores, Abel Ruiz, Abigail Reyes, Juan Manuel Rubio and Jun Wu
Toxics 2022, 10(6), 304; https://doi.org/10.3390/toxics10060304 - 3 Jun 2022
Cited by 5 | Viewed by 2654
Abstract
Lead (Pb) is an environmental neurotoxicant that has been associated with a wide range of adverse health conditions, and which originates from both anthropogenic and natural sources. In California, the city of Santa Ana represents an urban environment where elevated soil lead levels [...] Read more.
Lead (Pb) is an environmental neurotoxicant that has been associated with a wide range of adverse health conditions, and which originates from both anthropogenic and natural sources. In California, the city of Santa Ana represents an urban environment where elevated soil lead levels have been recently reported across many disadvantaged communities. In this study, we pursued a community-engaged research approach through which trained “citizen scientists” from the surrounding Santa Ana community volunteered to collect soil samples for heavy metal testing, a subset of which (n = 129) were subjected to Pb isotopic analysis in order to help determine whether contamination could be traced to specific and/or anthropogenic sources. Results showed the average 206Pb/204Pb ratio in shallow soil samples to be lower on average than deep samples, consistent with shallow samples being more likely to have experienced historical anthropogenic contamination. An analysis of soil Pb enrichment factors (EFs) demonstrated a strong positive correlation with lead concentrations, reinforcing the likelihood of elevated lead levels being due to anthropogenic activity, while EF values plotted against 206Pb/204Pb pointed to traffic-related emissions as a likely source. 206Pb/204Pb ratios for samples collected near historical urban areas were lower than the averages for samples collected elsewhere, and plots of 206Pb/204Pb against 206Pb/207 showed historical areas to exhibit very similar patterns to those of shallow samples, again suggesting lead contamination to be anthropogenic in origin, and likely from vehicle emissions. This study lends added weight to the need for health officials and elected representatives to respond to community concerns and the need for soil remediation to equitably protect the public. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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12 pages, 2319 KiB  
Article
Glycine Betaine Relieves Lead-Induced Hepatic and Renal Toxicity in Albino Rats
by Farid Abdelrazek, Dawlat A. Salama, Afaf Alharthi, Saeed A. Asiri, Dina M. Khodeer, Moath M. Qarmush, Maysa A. Mobasher and Mervat Ibrahim
Toxics 2022, 10(5), 271; https://doi.org/10.3390/toxics10050271 - 23 May 2022
Cited by 8 | Viewed by 2803
Abstract
Lead (Pb) is a widespread and nondegradable environmental pollutant and affects several organs through oxidative mechanisms. This study was conducted to investigate the antioxidant protective effect of glycine betaine (GB) against Pb-induced renal and hepatic injury. Male albino rats (n = 45) [...] Read more.
Lead (Pb) is a widespread and nondegradable environmental pollutant and affects several organs through oxidative mechanisms. This study was conducted to investigate the antioxidant protective effect of glycine betaine (GB) against Pb-induced renal and hepatic injury. Male albino rats (n = 45) were divided into three groups: G1 untreated control, G2 Pb-acetate (50 mg/kg/day), and G3 Pb-acetate (50 mg/kg/day) plus GB (250 mg/kg/day) administered for 6 weeks. For G3, Pb-acetate was administered first and followed by GB at least 4 h after. Pb-acetate treatment (G2) resulted in a significant decrease in renal function, including elevated creatinine and urea levels by 17.4% and 23.7%, respectively, and nonsignificant changes in serum uric acid levels. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphates (ALP) activities were significantly increased with Pb treatment by 37.6%, 59.3%, and 55.1%, respectively. Lipid peroxidation level was significantly increased by 7.8 times after 6 weeks of Pb-acetate treatment. The level of reduced glutathione (GSH-R) significantly declined after Pb-acetate treatment. Pb-acetate treatment also reduced the activities of superoxide dismutase (SOD), glutathione-S-transferase (GST), and glutathione peroxidase (GSH-PX) by 74.1%, 85.0%, and 40.8%, respectively. Treatment of Pb-intoxicated rats with GB resulted in a significant reduction in creatinine, urea, ALT, AST, and lipid peroxidation, as well as a significant increase in the level of GSH-R and in the activities of ALP, SOD, GST, and GSH-PX. The molecular interaction between GB and GSH-PX indicated that the activation of GSH-PX in Pb-intoxicated rats was not the result of GB binding to the catalytic site of GSH-PX. The affinity of GB to bind to the catalytic site of GSH-PX is lower than that of H2O2. Thus, GB significantly mitigates Pb-induced renal and liver injury through the activation of antioxidant enzymes and the prevention of Pb-induced oxidative damage in the kidney and liver. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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11 pages, 2436 KiB  
Article
Quantitative Estimation of Synergistic Toxicity of Cu and Zn on Growth of Arabidopsis thaliana by Isobolographic Method
by Bumhan Bae, Hyesun Park and Sua Kang
Toxics 2022, 10(4), 195; https://doi.org/10.3390/toxics10040195 - 16 Apr 2022
Cited by 5 | Viewed by 2997
Abstract
Heavy metal is one of the most frequent soil contaminants and contaminated soils generally include numerous metals. Although exposure to multiple metals may increase the toxicity to humans and ecosystems, only additive effects are considered in the risk assessment. In this study, the [...] Read more.
Heavy metal is one of the most frequent soil contaminants and contaminated soils generally include numerous metals. Although exposure to multiple metals may increase the toxicity to humans and ecosystems, only additive effects are considered in the risk assessment. In this study, the synergistic effect of heavy metals (Cu and Zn) on a model plant, Arabidopsis thaliana, was quantified by the isobolographic method. The plant was cultured via the growth assay method on a plant agar containing individual heavy metals or combinations of Cu + Zn in a growth chamber. The concentration of Cu varied by eight levels from 0 to 200 μM and the concentration of Zn also varied by eight levels from 0 to 400 μM. In the combination of metals, each of the three levels of Cu (25–75 μM) and Zn (20–100 μM) were applied. After 8 days, plants were harvested for root/shoot weight and measured for leaf chlorophyll and carotenoid content. The primary and secondary root elongation of A. thaliana was estimated using image analysis to calculate total root length. The EC50 values of Cu and Zn on A. thaliana, based on the total root length, were 40.0 and 76.4 μM, respectively. When two heavy metals were administered in combination, the EC values decreased less than those of the individual metals. The average value of the combination index was 0.6, proving the synergistic toxic effect on the root growth of A. Thaliana. As a result, the isobolograhic method is a useful tool for estimating the quantitative toxic effect of chemicals on plants. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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11 pages, 3749 KiB  
Article
Sequential Application of Column Leaching and Plant Uptake Tests to Assess the Effect of Various Commercial Amendments on Cu Immobilization in Ultra-High Cu-Contaminated Soil
by Tuan-Nguyen Quoc and Myung-Chae Jung
Toxics 2022, 10(4), 185; https://doi.org/10.3390/toxics10040185 - 10 Apr 2022
Cited by 1 | Viewed by 2147
Abstract
The presence of copper (Cu)-contaminated soil has increased recently due to agricultural and industrial activities. Immobilization techniques using soil amendments have attracted significant research because of their cost-effectiveness, eco-friendliness, and community acceptance. This study used various commercial amendments, including magnetite (M), talc (T), [...] Read more.
The presence of copper (Cu)-contaminated soil has increased recently due to agricultural and industrial activities. Immobilization techniques using soil amendments have attracted significant research because of their cost-effectiveness, eco-friendliness, and community acceptance. This study used various commercial amendments, including magnetite (M), talc (T), activated carbon (AC), and cornstarch (CS), to immobilize Cu in soil contaminated by acidic waste materials with Cu in Korea (9546 ± 5 mg/kg). To evaluate the immobilizing effect of these amendments, this study applied a sequential process of column leaching and plant uptake tests to observe the ability of Cu to remain in soil with and without amendments through the Cu removal rate. The amendments were characterized by SEM, XRD, and specific surface area and applied to the soil at a rate of 2% (w/w). The first stage of evaluation, i.e., the column leaching test, was conducted by continuously pumping distilled water (DW) for 28 days, and the second stage of evaluation, i.e., the plant uptake test, was started immediately after by planting 10-day-old lettuce seedlings for 28 days. The experimental results showed that all of the amendments had a significant effect on Cu immobilization Cu in soil (p < 0.05), and the T treatment showed the highest efficiency in Cu immobilization, with only 47.0% Cu loss compared to 73.5% in the control soil when assessed by sequential column leaching and plant uptake tests. In conclusion, this study provides an effective assessment method to evaluate the effect of amendments on Cu immobilization in soil, as well as providing feasible options to immobilize Cu using commercial amendments. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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22 pages, 1899 KiB  
Article
Revitalization of Total Petroleum Hydrocarbon Contaminated Soil Remediated by Landfarming
by Woo-Chun Lee, Jong-Hwan Lee, Sang-Hun Lee, Sang-Woo Lee, Ji-Hoon Jeon, Sang-Hwan Lee and Soon-Oh Kim
Toxics 2022, 10(3), 147; https://doi.org/10.3390/toxics10030147 - 19 Mar 2022
Cited by 6 | Viewed by 2924
Abstract
Soil health deteriorates through the contamination and remediation processes, resulting in the limitation of the reuse and recycling of the remediated soils. Therefore, soil health should be recovered for the intended purposes of reuse and recycling. This study aimed to evaluate the applicability [...] Read more.
Soil health deteriorates through the contamination and remediation processes, resulting in the limitation of the reuse and recycling of the remediated soils. Therefore, soil health should be recovered for the intended purposes of reuse and recycling. This study aimed to evaluate the applicability and effectiveness of several amendments to revitalize total petroleum hydrocarbon contaminated soils remediated by the landfarming process. Ten inorganic, organic, and biological amendments were investigated for their dosage and duration, and nine physicochemical, four fertility, and seven microbial (soil enzyme activity) factors were compared before and after the treatment of amendments. Finally, the extent of recovery was quantitatively estimated, and the significance of results was confirmed with statistical methods, such as simple regression and correlation analyses assisted by principal component analysis. The landfarming process is considered a somewhat environmentally friendly remediation technology to minimize the adverse effect on soil quality, but four soil properties—such as water holding capacity (WHC), exchangeable potassium (Ex. K), nitrate-nitrogen (NO3-N), available phosphorus (Av. P), and urease—were confirmed to deteriorate through the landfarming process. The WHC was better improved by organic agents, such as peat moss, biochar, and compost. Zeolite was evaluated as the most effective material for improving Ex. K content. The vermicompost showed the highest efficacy in recovering the NO3-N content of the remediated soil. Chlorella, vermicompost, and compost were investigated for their ability to enhance urease activity effectively. Although each additive showed different effectiveness according to different soil properties, their effect on overall soil properties should be considered for cost-effectiveness and practical implementation. Their overall effect was evaluated using statistical methods, and the results showed that compost, chlorella, and vermicompost were the most relevant amendments for rehabilitating the overall health of the remediated soil for the reuse and/or recycling of agricultural purposes. This study highlighted how to practically improve the health of remediated soils for the reuse and recycling of agricultural purposes. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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12 pages, 1670 KiB  
Article
Analysis of Major Bacteria and Diversity of Surface Soil to Discover Biomarkers Related to Soil Health
by Heejung Kim, Yong-Ha Park, Jae E. Yang, Hyuck-Soo Kim, Sung-Chul Kim, Eun-Ji Oh, Jinah Moon, Wonsil Cho, Wonsik Shin and Chaerim Yu
Toxics 2022, 10(3), 117; https://doi.org/10.3390/toxics10030117 - 1 Mar 2022
Cited by 11 | Viewed by 3574
Abstract
The discovery of biomarkers for assessing soil health requires the exploration of organisms that can explain the core functions of soil and identification of species with major roles in these functions. However, identifying specific keystone markers within the soil microbiota is challenging. Next-generation [...] Read more.
The discovery of biomarkers for assessing soil health requires the exploration of organisms that can explain the core functions of soil and identification of species with major roles in these functions. However, identifying specific keystone markers within the soil microbiota is challenging. Next-generation sequencing (NGS)-based molecular-biological methods have revealed information on soil biodiversity; however, whether this biodiversity is related to soil health remains unclear. In this study, we performed NGS on grassland surface soil to compare the prokaryotic and eukaryotic genetic diversity to determine the chemical soil quality and examined markers associated with soil health. Microorganisms associated with the nitrogen cycle, bioremediation, plant pathogenicity, antibiotic production, and material degradation showed potential for use as markers. To propose a framework for soil health assessment, we not only used traditional indicators, such as chemical and physical measures, but also assessed metagenomics data of soil by land use to identify the major factors influencing the microbial structure in soil. Moreover, major keystone species were identified. Furthermore, the microbial genetic diversity of generally healthy surface soil, such as forests, farmland, and parks, was determined. These findings provide basic data for exploring soil health-related biomarkers. Full article
(This article belongs to the Special Issue Heavy Metal Contamination in Soil and Health Risks)
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